Why you shouldnt trust blind testing and measurements in audio gear Not an Audio Review Channel 2026-06-09 | Last episode we talked about why you shouldn't trust reviewers and subjective impressions. This time, we're talking about why you shouldn't trust blind testing and measurements either. This should be fun and not at all controversial.Support me on Patreon at https://Patreon.com/notareviewchannel and get early, ad-free episodes and more for only $1. I’m a few weeks head now, so there’s bunch of videos on there that aren’t on YouTube yet. Thanks as always to my Patrons for their continued support.Join my Discord server: discord.gg/9RNPTUsAHeadphones.com SINAD video: youtu.be/DlwIGPEhfGU?si=P0EEMSTXLqoqBP8faPaper referenced in the video on the human auditory system: sciencedirect.com/science/article/abs/pii/S0003682X23003055Stereophile debate about blind ABX testing between John Atkinson and Arny Krueger: stereophile.com/content/great-debateand-then-some00:00 The trouble with measurements12:23 The trouble with blind testing14:06 The trouble with null tests15:30 The epistemological solution22:28 Embracing ambiguity25:55 The moral crusade of objectivism
You want an OTL (Eufonika H5 Headphone Amp/Preamp) Not an Audio Review Channel 2026-09-22 | OTL headphone/amp preamps are popular, less expensive ways to get into vacuum tubes. Let's talk about it.Eufonika website: https://www.eufonika.pl(Not an affiliate link)Mentioned in this video:* Eufonika H5 headphone amp/preamp* Eufonika H22S, H5H, and H7 headphone amps/preamps* Bottlehead Crack DIY headphone amp/preamp* Xduoo TA-84 headphone amp/preamp* Schiit Imp impedance multiplier* Xduoo TA-66, TA-26S headphone amps/preamps* Feliks Echo, Euforia, and Envy headphone amps/preampsTubes:* Apos Ray Select 6SN7* Svetlana 6N5S* RCA 6080 and 6SN7* Chatham 6SN7* Shuguang Treasure CV181-Z* Electro-Harmonix 6SN7* Cryotone 6SN7Support this channel at patreon.com/notareviewchannel for early, ad-free episodes and more!00:00 Intro01:22 What are OTL amplifiers?11:14 Why does this look like this? (the story)21:41 The sound
What esoteric and artisanal gets you (Devon Turnbulls Ojas Speakers) Not an Audio Review Channel 2026-09-07 | The Devon Turnbull Dream room at the Cooper Hewett and the speakers at the Ojas listening room in Manhattan give you a highly unusual audio experience with open baffles, horn drivers, and line arrays in custom designs. What does all that get you?Support this project at patreon.com/notareviewchannel where you can get early, ad-free episodes and more for only $1 a month
Streamers Dont Belong in Speakers Not an Audio Review Channel 2026-08-25 | It's time for another rant... this time it's about why you shouldn't buy speakers with built-in streamers and instead buy things that are built for the long haulSupport this project at patreon.com/notareviewchannel where you can get early, ad-free episodes and more for only $1 a month
Maybe the Internet was a mistake (the Apple //e) Not an Audio Review Channel 2026-08-18 | My childhood computer sucked and was also the best thing everSupport me at https://Patreon.com/notareviewchannel for early, ad-free episodes and moreDiscord Server: discord.com/invite/dtm9G8FPaB
The Amp Camp Preamp Plus Headphone Amp is Vindicated Not an Audio Review Channel 2026-08-11 | Felt like I had to make a new video about the DIY Audio Amp Camp Preamp + Headphone Amp after discovering that fixing the power supply made all the difference.Discussed in this video:* DIYAudioStore Amp Camp Preamp + Headphone Amp* A DIY power supply made with deadbug, point-to-point techniques* DIYAudioStore Whammy Headphone Amp/Preamp* ETA Audio DIY Associate Headphone Amp/Preamp* DIYAudioStore F5M Power Amp* Other things probablyDiscord server: discord.gg/dtm9G8FPaBConsider supporting me on Patreon at Patreon.com/notareviewchannel for early, ad-free episodes and more for only $1 a month
How far would you go for greatness? (Pass DIY F5M Power Amp) Not an Audio Review Channel 2026-08-04 | I went through a lot to get here, but it was worth it.Sorry about the lighting. I was experimenting with something and it didn't really work.Discussed in this video:* Pass Labs Aleph 5 Power Amp* FirstWatt F5 Power Amp* DIY Audio Store F5 Turbo Power Amp* DIY Audio Store F5M Power Amp* Parasound A23+ Power Amp* Brzhifi A1 Power Amp* DIY Audio Store Amp Camp Preamp + Headphone Amp* DIY Audio Store Whammy Headphone Amp/Preamp* ETA+System Dump Engineering Associate Headphone Amp/Preamp* Exploding circuit boards, rectifiers, transformers, wires, and more* How I f'ing hate chasses
How do you know an amp is really class A? Not an Audio Review Channel 2026-07-28 | Some people said the A1 I talked about in the last video couldn't really be Class A. Or could it?Support this channel at patreon.com/notareviewchannel for early, ad-free episodes and more for only $1.
BrzHifi A1 Class A Amp wins by default #amplifier Not an Audio Review Channel 2026-07-25 | What else can you get for $250 with this amount of power in Class A?
What happens when you clone a famous amp? Not an Audio Review Channel 2026-07-21 | What happens when you clone a famous amp and sell it for much less?Corrections:* It looks like this amp is actually 20W into 8ohms, not 25W.Discussed in this video:- BrzHifi A1 Integrated Amplifier- Musical Fidelity A1 Integrated Amplifier (OG and new edition)- Douk A5 Integrated Amplifier- Parasound A23+ power amplifier- DIYAudio F5M power amplifier- NBD MLTL-6 speakers- Q Acoustic Concept 30 speakers- Schiit Aegir power amplifierVideo showing how to disconnect the volume control from the amp: youtu.be/nkxfpDr2su4?si=jw8elBDYvtBSMHig00:00 Intro to the amp05:16 What's inside, what's different10:35 How does it sound?
Ads and YouTubers Not an Audio Review Channel 2026-07-17 | You can trust a paid YouTuber as much as you can trust any adExcerpted from Don't Trust Reviewers (or Me): youtu.be/2ApTpP7Xi_Q
The Audio ABX Testing Moral Crusade Not an Audio Review Channel 2026-07-15 | Why for some people whether audio gear is good or not isn't merely a scientific issue, it's a moral oneExcerpted from "Why You Can't Trust Blind Testing and Measurements": youtu.be/IBc_HtZ9038
Price and Value in Audio? (Burson Conductor GT4) Not an Audio Review Channel 2026-07-14 | The Burson Conductor GT4 Deluxe Edition is a $3,400 headphone amp/preamp/DAC. How do we think about why this has the price it does and what that means in terms of the larger market?Update: Burson has clarified for me that the icon blinking is by design, saying "The Conductor resamples the incoming signal every few seconds. In that moment of resampling, you get this little blink from the icon." They have said they'd get back to me about the other issues I found, and when they do I will update here.Update 2: Burson asked me to try and rectify the issue with the loud thumps by taking out and reinstalling the op-amps on the right side and making sure the silent power modules are firmly seated. They also suggested I could try putting the 5532 op-amps back in and see if the problem still persists, which would tell me if there's a fault with the op-amps. While I didn't notice the issue with the 5532 op-amps, I didn't have them in for more than a day and in a couple weeks of testing with the other op-amps I only experienced the issue twice, so I'm not sure I'm interested in continuing to troubleshoot this particular unit. However, if I had actually purchased it, I would do these things and maybe they would resolve the issue or if the op-amps were faulty I assume I could get them replaced.Headphone Show video about the Burson Conductor 3X Reference: youtu.be/R9cFXxGIY4Y?si=sbW0Q4cvAdLMfGwNSpecial thanks to GoldenSound for his input.You can support me at patreon.com/notareviewchannel and get early, ad-free episodes and more for only $1.Also mentioned:- Burson Super Charger Power Supply- Burson V7 Vivid Op-Amps- JRC 5532 Op-Amps- PS Audio DirectStream DAC Mk. 1- SMSL VMV D2R DAC- Schiit Modi DAC- Schiit Magni Headphone Amp/Preamp- Aune S17 Pro Headphone Amp/Preamp- DIY Associate Headphone Amp/Preamp (circuit board available at: etaheadphones.com/products/associate-amplifier?variant=48785129898280 (not an affiliate link))- DIYAudioStore Amp Camp Preamp + Headphone Amp
Are R2R DACs better than Delta-Sigma? Not an Audio Review Channel 2026-07-10 | Are R2R DACs and even NOS (non-oversampling) R2R DACs better or more accurate than Delta Sigma DACs?
How Amplification Works (All of It) Not an Audio Review Channel 2026-07-07 | Video edits together material from my other videos to do a complete run down of electronic amplification, from the origin of vacuum tubes, Class A, Class B, Class AB, Class D, op-amps, negative feedback and more, all carefully put together to make a seamless whole. Enjoy!You can get early, ad-free episodes and more for only $1 at patreon.com/notareviewchannelIncludes material from:* Does Feedback Actually Ruin Sound?* All Op-Amps Are Not Made the Same* Can Op-Amps Beat Discrete Designs?* Class AB Amplification Gave Me a Stroke* Why Class D Breaks My BrainEnjoy!0:00:00 Intro0:01:40 Vacuum Tubes and Amplification0:05:12 Single-Ended Class A0:09:10 Class B part 10:10:23 Silicon and Doping0:12:41 Transistors0:17:46 Class B part 20:19:59 Conventional Current0:20:31 Class AB with Transistors0:24:23 Class AB with Tubes0:28:11 Push-Pull Class A0:31:44 Negative Feedback0:36:57 Op-Amps and ICs0:44:20 Discrete Op-Amps0:44:53 Buffer Stages0:50:56 Intro to Class D0:52:45 How Class D works0:55:24 Square Waves and Harmonics0:58:05 Class D and Efficiency0:58:36 GaN transistors1:00:09 Load Dependency1:01:51 Outro
Digital Audio Broke My Brain Not an Audio Review Channel 2026-06-30 | This video... this was a lot of work guys, I hope you like it. Digital Audio is stupidly complicated. Also I'm going to raise up the camera goddamn it, I swear this is going to be the last video I make where I'm looking down my nose at you most of the time, this is ridiculous.Corrections:- when I say “bit rate” I mean “bit depth”Support this project at patreon.com/notareviewchannel where you can get early, ad free episodes and more for only $1My video about Class D amplification which covers some similar ground: youtu.be/pdhvJ0sw4egMy video about Class AB amplification and how weird it is: youtu.be/Ps7hU9DLGM8 (also covers Class A amplification---Primary source: Principles of Digital Audio by Ken C PohlmannThough as usual any errors here should probably be attributed to me and not PohlmannMore information about duplexing telegraph lines from the excellent digital antiquarian blog: filfre.net/2022/02/a-web-around-the-world-part-4-from-telegraphy-to-telephonyOn 16 bit audio: biberfan.org/musings/2025/9/6/understanding-high-resolution-audioVideo about the PS Audio DirectStream DAC, which is a DSD DAC: youtu.be/UolnQ0nWV20Video where I talk about my weird sensitivity to R2R DACs: youtu.be/-4WUYFZRiok0:00:00 Intro0:00:58 How Analog Works0:02:49 Why Digital?0:04:08 Pulse Code Modulation0:12:18 Aliasing0:13:45 High Frequency Noise0:15:45 Quantization Error0:18:32 Oversampling and Noise Shaping0:23:40 R2R DACs0:26:19 Delta-Sigma DACs0:33:01 DSD vs. PCM0:34:32 R2R vs. Delta-Sigma0:36:57 Jitter and Clocks0:38:48 In the end...
Class AB Gave Me a Stroke (fixed!) Not an Audio Review Channel 2026-06-24 | New version of the Class AB video which fixes mistakes in the previous version which is now unlisted.Class AB amplification might not work how you think, especially when done with vacuum tubes. Why was this the standard way of doing electric amplification for decades and is still widely used in lots of use cases?Support this project at patreon.com/notareviewchannel for early, ad free episodes and more for only $1.For those of you who watched the previous version of the video, these are the TL;DR corrections: JFETs actually conduct with nothing on the gate just like vacuum tubes. N-channel JFETs are biased in Class A with negative voltage, not positive, because that reduces the amount of current passing through the tube. (To make things more complicated, BJTs and "enhancement mode" MOSFETs (which are most MOSFETs) however DON'T conduct when there's nothing on the gate, and so DO need positive voltage for N-channel or NPN like I originally described.) JFETs and MOSFETs are N-channel or P-channel, NOT NPN or PNP (which are terms usually reserved for BJTs). To make a Class B JFET amp you need to add enough negative bias to the N-channel transistor so it will not conduct when there's no signal, and enough positive bias to the P-channel transistor for the same. To make Class AB you then add a little bit of positive to one and a little negative to the other. BJTs and enhancement mode MOSFETs though work in Class B without any bias current like I originally described. Tube amps, like N-channel JFETs, need a negative bias current to be used in Class B. Also semiconductor diodes have a negative doped cathode hooked up to the negative voltage source and a positive doped anode hooked up to the positive voltage source, not the reverse as I said. The rest is basically like I described. And now I'm going to put this in the description for everyone else.Corrections for THIS video: (because goddamnit there's more and I'm not recording a new version again)* The semiconductor diode illustration is incorrect, in fact the cathode is doped negative and connected to the negative voltage source and the anode is doped positive and connected to the positive voltage source.* P-channel and PNP transistors, the terms are actually switched between source/drain and emitter/collector, meaning that they call the end that's connected to the positive voltage source the source/emitter and the end that's connected to the negative voltage source the drain/collector rather than the other way around like it is on N-channel and NPN transistors. Thus the source follows the gate in both cases, even though the electrons still flowing from negative to positive.ElectroBoom on how capacitors work: youtu.be/rbCXKhhzBN0?si=xvx9C1lar1W216kvNelson Pass lecture about high bias Class AB: youtube.com/watch?v=TApRmUpuZSgNelson Pass article about Class A and bias: firstwatt.com/wp-content/uploads/2024/01/art_leaving_class_a_2019_redux.pdfNelson Pass article on distortion and feedback: passlabs.com/technical_article/audio-distortion-and-feedbackHow semiconductors are doped: circuitbasics.com/what-is-a-diode00:00 Apologies00:14 Intro02:02 Single-Ended Class A07:28 Class B, N Channel08:46 Semiconductors16:41 Class B, P Channel18:55 On Conventional Current19:27 Class AB23:23 Class AB with Tubes27:14 Push-Pull Class A
You dont need surround sound and Atmos Not an Audio Review Channel 2026-06-16 | Surround sound sucks, actually, and Dolby wants you to pay more for the privilege of having it, abetted by Apple. This is why you only actually need stereo.Benn Jordan's deep dive into the problem with Atmos for music: youtube.com/watch?v=5Dw3aKbw5WoSupport me on Patreon at patreon.com/noareviewchannel where you can get early, ad free episodes and more for only $1.
Why you shouldnt trust audio gear reviewers or subjective impressions Not an Audio Review Channel 2026-06-02 | Some surprises in this one...Note that I forgot Crinacle doesn't actually do reviews anymore, I'm still referring to him as a reviewer here, sorry.Link to the Headphone Show video I reference:youtu.be/xtyri3F5YisMy old video about hearing differences in power cables: youtu.be/9RyZBVY8yc000:00 Buckle Up02:40 People want to rip you off07:30 HRTF and personal taste09:31 Reviewers developing relationships with manufacturers14:36 When everything is the best16:50 Affiliate links19:06 Friendships with manufacturers20:30 Unconscious bias23:22 Embracing ambiguity
A Transmission Line is the key to crazy bass without a sub Not an Audio Review Channel 2026-05-26 | The NBD MLTL-6 speakers are the best speakers (for me). Let me tell you why, and also how you can get bass flat down to 15hz without a subwoofer.Support me on Patreon at patreon.com/notareviewchannel and get early, ad-free episode and more for only $1!00:00 The Neil Blanchard Designs MLTL-6 Speakers03:48 Speakers made by an evil wizard18:54 How they sound25:56 Headphones are different than speakers27:21 Why they're the best speakers for me
Why I spent more than I ever thought I would on a pair of headphones Not an Audio Review Channel 2026-05-21 | The ZMF Atriums are the best headphones for me. But they may not be the best headphones for you. Let's talk about why.Headphones.com video about HRTF and how everyone hears differently: youtube.com/watch?v=xtyri3F5YisSupport me on Patreon at [http://Patreon.com/notareviewchannel](http://patreon.com/notareviewchannel) for early, ad-free episodes, exclusive content and more for only $1!
Do you need a balanced headphone adaptor? Not an Audio Review Channel 2026-05-17 | Discusses balanced and single-ended headphone connections and whether and how you can convert one to the other
Do you need balanced conversion? Not an Audio Review Channel 2026-05-12 | Overview of balanced conversion methods including cables, transformer boxes, and active convertersAtomicBob post on SBAF I reference in the video: superbestaudiofriends.org/index.php?threads/audio-balanced-output-to-unbalanced-input-a-brief-visual-guide.7012Support me on Patreon at Patreon.com/notareviewchannel for early access to ad-free videos, exclusive content and more for only $1
How do amplifier classes work? Not an Audio Review Channel 2026-05-10 | Overview of class A, B, and AB amplifier classes with a lead-in for the full treatment of Class D in the longer video
Do you actually need balanced audio? Not an Audio Review Channel 2026-05-05 | Let's talk about how balanced audio works and whether you actually need it for home hifiSupport me on Patreon at patreon.com/notareviewchannel for early, ad-free episodes, exclusive content and more for only $1Thanks to my Patreons who help make this all possible!Headphones.com article about balanced design: headphones.com/pages/balanced-headphones-guideSpecial thanks to GoldenSound and HelioCat on the Headphones.com Discord Server for their patience in walking me through some of the concepts here.Corrections:* Balanced amplifiers have a lower noise floor but only if you're operating in the volume range where you need that extra voltage* Rubber insulation does not reduce EMI, you need to have a shielded cable where the shield around the cable is connected to ground* Balanced cables also reduce crosstalk, which is an issue where the shared ground wires of a single-ended connection can cause interference in the signal. For shorter cable runs, the effects of crosstalk on a single-ended signal should theoretically be inaudible.00:00 The answer to the question00:38 Why are you still here?01:00 Okay, fine, I'll tell you about balanced audio13:08 But do you actually need it?
How do vacuum tubes work? Not an Audio Review Channel 2026-05-03 | How do vacuum tubes work? An excerpt from: youtu.be/pieTngvrhuE
They got power, but can they sing? (Orchard Audio Starkrimson 25 Monos and Parasound A23+) Not an Audio Review Channel 2026-04-28 | Can the indy amp using the latest tech challenge an old-school, big brand beast? Let's find out.Here's the paper I reference in the video: researchgate.net/publication/370537927_The_Human_Auditory_System_and_AudioCorrection:* Apparently you can adjust the gain of the Starkrimsons by changing an internal jumper, which I was not aware of when I made the video* Apparently these were actually the version of the amps with the op-amp buffer stage and I didn't known! If I'd known I would've tried some different op-amps in there, I don't even know what it was running with.Support me on Patreon at patreon.com/notareviewchannel for early, ad-free episodes, exclusive content, and more for only $1!Mentioned in this video:* Orchard Audio Starkrimson 25 Mono power amplifiers* Douk A5 integrated amplifier* Parasound A23+ power amplifier* Atoll MA100 power amplifier* NBD MLTL-6 speakers* JBL L82 speakers* Eufonika H5 OTL tube headphone amp/preamp* DIYAudio Whammy Headphone Amp/Preamp* SDE/ETA Associate Headphone Amp/Preamp* PS Audio DirectStream mk. 1 DAC* SMSL VMV D2R DAC00:00 Starkrimson 25 Monos vs. Douk A502:45 Starkrimson 25 Monos vs. Parasound A23+11:35 Monos on the JBL L82s vs. Atoll MA10013:20 Monos on the NBD MLTL-6s vs. Parasound A23+
Class D Amplification Breaks My Brain Not an Audio Review Channel 2026-04-21 | Class D amplification breaks my brain. Let me tell you about it!Photo at 16:17 courtesy of JTSupport me on Patreon at patreon.com/notareviewchannel for early, ad-free episodes, exclusive content, and more for only $1!Corrections:* Most Class D amps actually use inductors as well as capacitors and resistors for their low pass filter implementation, but the effect of the speaker load on the filter is essentially the same* A number of folks pointed out that the PWM high frequency noise doesn't work quite the way I describe (in a stair-step fashion). As I've discussed before, I'm not an expert, so I reached out to someone who is: Bob Cordell, author of the books Designing Audio Power Amps and Designing Audio Circuits and Systems. Bob wrote: "There are two minor areas that can cause confusion and disagreements about semantics. Your illustration of the raw rectangular output of a class D amplifier depicts positive and negative pulses that return to zero, then go to the other polarity - these are not really simple rectangular pulses. That is not how most class D amplifiers work. Most class D amplifiers create pulse-width modulated rectangular waveforms that transition from zero to a positive voltage and back to zero. Some create pulses that transition from a negative voltage to a positive voltage, but they do not stop in the middle at zero. For a relative positive output, the pulse is wider when is at the positive voltage and narrower at the zero voltage. The opposite is true for a negative output voltage. for a zero average output signal level, as at the center of a sine wave, the output is simply a square wave with a 50% duty cycle.The other source of possible confusion or disagreement is your use of the term stairstep and the corresponding depiction. The stairstep never really exists before the output filter, and does not really exist after the typical filter. The output of a proper filter is a continuous analog waveform with no such edges."I responded: "Though the shape is not a stair-step, the high frequency noise that the low pass filter filters out (as I describe in the video) exists because of the square/rectangular wave forms of the PWM, correct?"And he responded: "That is correct."So there you have it.Discussed in this episode:* DIY Audio F5M power amplifier* Atoll MA100 power amplifier* Parasound A23+ power amplifier* Douk A5 integrated amplifier* Orchard Audio Starkrimson 25 mono block amplifiers
Two radically different takes on desktop speakers (Copperheads and iLoud Micro Monitors) Not an Audio Review Channel 2026-04-14 | Two radically different takes on small speakersSupport me on Patreon for early, ad-free videos, exclusive content, and more. patreon.com/notareviewchannelMentioned in this video:* Closer Ogy speakers* PartsExpress Copperhead kit speakers* iLoud Micro Monitors* JBL Pulse 5 bluetooth speaker* Sennheiser HD6XX headphones* Douk A5 amplifier* Schiit Magni headphone amp/preamp* Schiit Modi DACChain: Eversolo T8 streamer, PS Audio DirectStream DAC, Parker Associate headphone amp/preamp, Parasound A23+ power amplifier00:00 What are full range speakers?07:15 The Closer Ogys09:13 Making the Copperheads15:00 The iLoud Micro Monitors21:39 So how do they sound?24:25 Sound demo25:45 Some caveats
Can op-amps beat discrete designs? (Whammy, Associate, and op-amps) Not an Audio Review Channel 2026-04-09 | This may have gotten a little out-of-hand...There's an audio drop-out around the 9 minute mark. What I'm saying is that the ACP+, the Whammy, and some other amps make it so when you insert the headphone plug into the jack it automatically turns off the preamp outputs and turns them back on when you remove it, which is a perfectly acceptable solution but still not as good as having a switch.Correction:* Actually a lot of integrated op-amps don't have as low output impedance as I state here. The NE5532 for example has a low closed loop output impedance (about 0.3 ohms) and a lot of nice audio op amps are under 1 ohm, but they are usually like 0.X to 0.0X range. So the NE5532 would actually have a 3x higher output impedance if the buffer is 0.1 ohms. (Thanks to @control_voltage for this correction.)Buy your Associate boards: etaheadphones.com/products/associate-amplifier(Not an affiliate link, not a paid ad, but ETA do support me on Patreon because they're awesome)The Hammond chassis I used: amplifiedparts.com/products/chassis-box-hammond-extruded-aluminum-866-x-406-x-209Folder with the op-amp recordings: dropbox.com/scl/fo/qidvwz37fukt5yrf9dcta/AADYBkty3Nb4MaG7GMU8ozg?rlkey=2z7gpjm7jgcgkmhk8pl0r33de&st=2356zsuz&dl=0Pow Chu Moy's article about designing the CMoy amp and op-amp designs in general: headwizememorial.wordpress.com/2018/03/08/designing-an-opamp-headphone-amplifierOp-Amps: NE5532, RC4580IP, OPA2132, Muse02, Burson Vivid, Burson Classic, Sparos SS3602, Sparkos SS2590Amps: Associate, Whammy, Amp Camp Preamp+Headphone Amp, Douk A5Rest of the chain: Eversolo T8 streamer, Parasound A23+ power amp, NBD MLTL-6 speakers, Sennheiser HD6XX headphones, ZMF Atrium, ETA Ada000:00 Introduction005:33 Making the Associate015:47 Why does the Whammy have parts the Associate doesn't?030:28 The power supply changes everything042:10 Amp Camp Preamp + Headphone Amp vs. The Whammy046:16 The Associate Comes Alive053:49 How the different op-amps sound in these amps
All Op-Amps Are not Made the Same Not an Audio Review Channel 2026-03-31 | Why would one op-amp sound different from another? Let's talk about how they work and ideas and evidence of why and how they sound differentCorrections:* I say here that if you put the signal in the inverting input you can put feedback from the output in the non-inverting input. This is incorrect and would just re-amplify the input and cause oscillation and failure. And if you didn't hear me say that it's because I edited out the part of the video where I say it so it's not there anymore.* One point made by a commenter is that the high gain of an op-amp has less to do with maximum flexibility as I say here and more to do with approaching a mathematical ideal of "infinite" gain which in theory maintains more consistent (or ideal) operation (hence "operational amplifier").* A single resistor doesn't actually reduce the negative feedback by itself, it needs to be part of a voltage divider* Per a commenter who works in a semiconductor fab, integrated circuits, particularly the computer CPUs I mention, "are not made by a machine, they are made by many, many, many machines. The machine pictured does not cost millions of dollars. It costs hundreds of millions of dollars."Support me on Patreon for early, ad-free videos, extra material like my CanJam 2026 impressions, chat with me and more for only $1: patreon.com/notareviewchannelAudio Science Review video about op-amps: youtu.be/nGy-Q8jKXr4?si=mUTLIeGdWB-Ef-sKAnalogholic video about op-amps: youtu.be/nQS030YSiWk?si=DQ1ORbMPp9D5JWYTSparkos white-paper on two-pole feedback design: sparkoslabs.com/discrete-op-amps/audio-op-amps-gain-seek-bandwidthFosi video comparing op-amps: youtube.com/watch?v=nrqVYE4_v1MVirtual Hifi video comparing op-amps: youtube.com/watch?v=kNDX7SCN6JcFolder with my unlabeled op-amp recordings: dropbox.com/scl/fo/qidvwz37fukt5yrf9dcta/AADYBkty3Nb4MaG7GMU8ozg?rlkey=2z7gpjm7jgcgkmhk8pl0r33de&st=2356zsuz&dl=0
The one weird trick which transforms the Schiit Mimir DAC Not an Audio Review Channel 2026-03-25 | I have the Schiit Mimir for a week, and discover it can do things that no other DAC in its price category can doUpdate: Eufonika is still selling gear, just not on Etsy! Check out their stuff at: https://www.eufonika.pl(Not an affiliate link, I have no financial relationship with Eufonika.)Support me on Patreon: patreon.com/notareviewchannelFor early, ad-free episodes, exclusive content, and chat with me!Paper: "The Human Auditory System and Audio" by Milind N. Kunchur, 2023: arxiv.org/pdf/2307.00084Discussed in this episode:* Schiit Mimir DAC* Schiit Modi+, Mesh Modi, Magni+, Magni Unity* Schiit Asgard X, Schiit Midgard* SMSL D300 DAC* SMSL VMV D2R DAC* Eufonika H5* Parker Litchfield Associate* DIY Audio Whammy* Aune S17 Pro* HQPlayer* Xduoo TA-66, DarkVoice 336SE, Bottlehead Crack, Feliks Echo, Feliks EuforiaIn addition the mentioned gear, I used this DAC with a number of headphones including the ZMF Atrium, the Sennheiser HD6XX (Custom Cans modded), the Fiio FT1 Pro, the ETA Mini S, and ETA Ada. I also used it on my MLTL-6 speakers with the Parasound A23+ power amplifier.
Does feedback actually ruin sound? Not an Audio Review Channel 2026-02-22 | There's a claim you'll hear that the feedback required for transistors causes "time smearing" which affects soundstage, dimensionality, and "openness". Is there any truth to this?Corrections:* A single resistor doesn't actually reduce the negative feedback by itself, it needs to be part of a voltage dividerBibliography:* Steve Deckert from Decware Asks Is Hifi Really Lofi? youtu.be/vS7AgsEpaSM* Decware's Steve Deckert talks about Fidelity and Power: youtu.be/BtI7mTbAk00* Designing High-Fidelity Tube Preamps by Merlin Blencowe* Designing Audio Circuits and Systems by Bob Cordell* Re-Entrant Distortion: should we worry? audioxpress.com/article/audio-myths-feedback-re-entrant-distortion-should-we-worry* Distortion and Feedback sound-au.com/articles/distortion+fb.htm* Hegel's Feed-Forward Feedback system youtube.com/watch?v=ER_lqNFckxY
How they ruined the best wireless headphones (Sennheiser HDB630) Not an Audio Review Channel 2026-02-05 | You can't replace the batteries. At all. Ever.Correction:* Sonova is a Swiss company, not GermanDiscussed:* Sennheiser HDB630* Sony WH-1000XM3* Sennheiser HD600* Drop x Sennheiser HD6XX* Sennheiser HD560S* Sennheiser HD580* Sennheiser HD660S* Sennheiser HD660S2* Sennheiser HD550
Can it beat the champ? (PS Audio Airlens vs. Eversolo T8 audio streamers) Not an Audio Review Channel 2026-01-30 | How does the PS Audio Airlens compare to the Everosolo T8 that I talked about in my last streamer video and remains my champ for audio streaming devices?Discussed here:* PS Audio Airlens Streamer* Eversolo T8 streamer* Modded Whammy headphone/amp preamp with Sparkos SS2590 op-amps* Modded Eufonika H5 headphone amp/preamp* Brzhifi clone of the Musical Fidelity A1 amplifier (volume control bypassed)* NBD Tower 4 speakers* Schiit Loki/Lokius/Loki Max analog EQ* MiniDSP Flex digital EQ* Hiby R6 III DAPThomas in Stereo and HifiCave talk about the Pink Faun streamer: youtube.com/watch?v=XlZoJKmamH8Paul McGowan on why PS Audio gear doesn't have tone controls: youtu.be/a3Rjg7Wa09AChain: DIY Musical Fidelity X10-D tube buffer clone, modded Whammy headphone amp/preamp w/ Sparkos op-amps or modded Eufonika H5 or Parker Associate, Brzhifi clone of the Musical Fidelity A1 amplifier or Parasound A23+ power amplifier, NBD Tower 4 speakers or Q Acoustic Concept 30s, Paragon Defiance V10 subwoofer. Listening done mostly using Qobuz or Apple Music.
DIY Midrange Magic (NBD Tower 4) Not an Audio Review Channel 2026-01-11 | DIY mini towers with a transmission line sound the way I hoped Harbeths would before I bought them, with a crazy organic midrangeTechnical information about transmission line speakers: transmissionlinespeakers.com/en/articles/introduction-and-historical-notesDiscussed in this video:* Neil Blanchard Designs Tower 4 DIY speakers* Q Acoustics Concept 30 speakers* JBL L82 speakers* Harbeth P3ESR speakers* Atoll MA100 power amplifier* Brzhifi A1 amplifier (clone of the Musical Fidelity A1)* Drop x Sennheiser HD6XX headphonesCurrent chain:Home office: Eversolo T8 streamer-PS Audio DirectStream DAC mk. 1-DIY clone of the Musical Fidelity X10D tube buffer-Custom DIY Audio Whammy headphone amp/preamp-Parasound A23+ power amplifier or Brzhifi A1 amplifierLiving room: Wiim Ultra streamer-Atoll MA100 power amplifierMost music streamed via Qobuz Connect or Apple Music
New tech in an old suit (Schiit Magni Unity/Modi 5 vs. Magni+/Modi+) Not an Audio Review Channel 2026-01-03 | Got my father the new Magni Unity and Modi 5 stack and I'm putting it up against the Magni+/Modi+ stack that it replaced with the HD6XX headphonesApologies for the poor audio quality as this was recorded at my father's house without my usual mic and set-upAll music was streamed off an iPhone to the Modis via USB using a generic USB cable. The RCA cables connecting Modi to Magni are Schiit Pyst cables.References:* Schiit's Jason Stoddard on the Magni Unity technology: head-fi.org/threads/schiit-happened-the-story-of-the-worlds-most-improbable-start-up.701900/page-8726#post-17831390* Schiit's Mike Moffat on the "Supercomboburrito" DAC filter: head-fi.org/threads/new-schiit-ragnarok-and-yggdrasil.667711/page-331#post-11396780Mentioned here:* Schiit Magni+ headphone amp/preamp* Schiit Modi+ DAC* Schiit Magni Unity headphone amp/preamp (aka just "Magni")* Schiit Modi 5 DAC* Drop x Sennheiser HD6XX headphones* Schiit Mimir DAC* SMSL VMV D2R DAC* DIY Audio Whammy headphone amp/preamp* Aune S17 Pro headphone amp/preamp* PS Audio DirectStream DAC Mk. 1
Does the Eversolo T8 beat the $4k A10? (also vs. Wiim Ultra, Node (2021), Pi2AES 2.0) Not an Audio Review Channel 2025-12-10 | In a sequel to my last video, does the Eversolo T8 beat the $4k A10 or is it worth spending more even if you're only using it as a streaming transport?Don't buy from Amazon, buy from Bloom Audio: http://bloomaudio.com(Not an affiliate link, not a paid sponsorship, though Bloom did lend me the Eversolo DMP A10)Discussed in this video:* Eversolo T8 Streaming Transport* Everolo DMP A10* Wiim Ultra* Bluesound Node (2021)* Raspberry Pi 4* Pi2Design Pi2AES 2.0 HAT* PS Audio DirectStream Mk. 1 DAC* PS Audio Bridge 1 Streaming Card
Streamer Wars (Wiim, Bluesound, Pi, Eversolo) Not an Audio Review Channel 2025-12-07 | In my experience, any streamer is better than a PC, even with an expensive DDC, isolator, and fancy cables. But is it worth spending more money on a more expensive streamer or can you get the same sound for dramatically less? And will the user experience and features add up for you? Well, for me, anyway, this isn't a review channel.Don't buy from Amazon, buy from Bloom Audio: bloomaudio.com(Not an affiliate link nor a sponsorship, though Andrew from Bloom leant me the Eversolo DMP A10)Corrections:* I flipped this in my head, iWii actually says the T8 sounds better as a transport than the A8, not the reverse. I'm going to see if I can edit that out of the video* The Wiim apparently can ALSO do subwoofer delay like the Eversolo and test for timing between the main speakers and the subs, which is pretty remarkable.Timestamps:0:00 Intro, DDC vs. Pi5:38 About my set-up, streaming services, and connection methods9:22 Wiim Ultra13:18 Bluesound Node (2021)16:48 Eversolo DMP A1019:06 Raspberry Pi w/ Hifiberry Digi+ Pro and Pi2Design Pi2AES 2.0 hats36:43 Bottom lineDiscussed in this episode:* Matrix Audio X-SPDIF 3 DDC* JDS Labs Snapse USB isolator* Raspberry Pi 4* Hifiberry Digi+ Pro HAT* Pi2Design Pi2AES 2.0 HAT* Bluesound Node (2021)* Wiim Ultra* Eversolo DMP A10* Eversolo T8 Streaming Transport* Pi2Design Mercury Mini streamer* Holo Red* Volumio Rivo+* Volumio OS* Ropieee* Moode* PiCorePlayer* Lyrion Music Server* Roon* Audirvana
Headphone amps shouldn’t have low power speaker outputs Not an Audio Review Channel 2025-11-12 | Why would you put low power speaker posts on a headphone amp instead of preamp outputs?Gear discussed:* Galion Victoria Headphone Amp* Amp Camp Preamp + Headphone Amp* Schiit Magni+* Too many other headphone amps to name
The worst measuring, best sounding DAC (PS Audio DirectStream Mk. 1) Not an Audio Review Channel 2025-11-03 | How can a DAC that measures so poorly sound so good?References: * PS Audio CEO Paul McGowan on DSD vs. PCM: youtube.com/watch?v=JN-cfEniluU* Paul McGowan answers some questions on the DAC functionality: forum.psaudio.com/t/directstream-functionality/42883/5* Stereophile Review of the DirectStream Mk. 1: stereophile.com/content/ps-audio-perfectwave-directstream-da-processor-page-2* List of albums with inverted phase: head-fi.org/threads/all-tracks-on-approximately-92-of-compact-discs-cds-play-in-inverted-polarity-on-approximately-92-of-compact-disc-players.793663/#post-12227272* Erin from Erin's Audio Corner talking about phase and "Money for Nothing": youtube.com/shorts/pPobYh4ZpW4Mentioned in this video:* PS Audio DirectStream Mk. 1* PS Audio DirectStream Mk. 2* PS Audio PMG Signature 512 DAC* SMSL VMV D2R DAC* Holo Cyan 2* Amp Camp Preamp + Headphone Amp* Aune S17 Pro (which name I still mispronounce)* Drop X Xduoo TA-84* Ferrum Oor* Musical Fidelity X-10D tube buffer clone* Matrix X-SPDIF 3 DDC* Drop X Sennheiser HD6XX headphones* PS Audio PerfectWave PowerPlant 5Other equipment used:* Parasound A23+ Power Amplifier* Q Acoustics Concept 30 speakers* ZMF Atrium headphones and other headphones
I fixed my ACP+ and its amazing now Not an Audio Review Channel 2025-09-29 | It was broken! I made a booboo! It's great now! But maybe it could use something extra...Stuff in this video:* Amp Camp Preamp + Headphone Amp* Clone of the Musical Fidelity X-10D* Aune S17 Pro* Drop x Xduoo TA-84* Ferrum Oor* Drop x Sennheiser HD6XX* Sennheiser HD660S2* ZMF AtriumMy set-up includes: SMSL VMV D2R or Mystery DAC, JDS Labs Synapse, Matrix Audio X-SPDIF 3 DDC, Parasound A23+ power amp, Q Acoustic Concept 30 speakers
Is the blackest background enough? (Ferrum Oor) Not an Audio Review Channel 2025-08-12 | Clean with a black background, is it enough to unseat my favorite amps? Also, Ferrum owner Hem's betrayal of MytekGear talked about:* Ferrum Oor* Aune S17 Pro* Xduoo TA-84* SMSL VMV D2R DAC* Mystery DAC (to be revealed!)* HeadAmp GS-X Mini* Ferrum Wandla and Hypsos* Mytek Brooklyn Bridge II* Parasound A23+* Q Acoustic Concept 30 speakers* Sennheiser HD6XX* ETA Ada and Mini S headphonesOther gear used: PS Audio P5 Power Regenerator, Matrix X-SPDIF3 DDC, JDS Labs Synapse
Lets add distortion to make things sound better (X10-D clone, H2 Harmonic Generator, and plug-ins) Not an Audio Review Channel 2025-07-23 | Let's do a deep dive into harmonic distortion, why it makes things sound better, and whether we can use some homemade devices and plug-ins to bring the magic of tubes to solid stateCorrections:* It seems that 3 db lower is half as much power but not half as much loudness. 10db lower is half as much loudness.* An open "A" string on a guitar is actually A110. A440 is two octaves above that.00:00 - Begin00:47 - What’s wrong with tubes?03:44 - A brief history of tubes05:03 - What is harmonic distortion and why is it good?13:36 - About the X10-D Tube Buffer22:00 - About the H2 Harmonic Generator29:28 - Testing gear30:48 - Sound of the X10-D32:16 - Sound of the H2 Harmonic Generator35:39 - The secret revealed40:04 - The sound of simulator plug-ins41:20 - ConclusionDiscussed here: * Clone of the Musical Fidelity X10-D tube buffer* DIY Audio H2 Harmonic Generator (designed by Nelson Pass)* WaveArts Tube Saturator Vintage* Melda MPolySaturator* ViatorDSP StimulateMy set-up: SMSL VMV D2R - Aune S17 Pro OR Drop x Xduoo TA-84 OR Ferrum Oor - Parasound A23+ - Q Acoustic Concept 30s + Paradigm V10 sub
Can I Build Solid State that Sounds Like Tubes?(DIY upgraded Nelson Pass Amp Camp Pre+Headphone Amp) Not an Audio Review Channel 2025-06-18 | So I built a headphone amp/preamp. I also built a linear power supply for it. It's supposed to sound "tubey". Does it? And how does it stack up to my Xduoo TA-84 and Aune S17 Pro?Important update: the folks at DIYAudio noted that the harmonic distortion I mention in this video doesn't match how the ACP+ is supposed to perform. After reviewing my build with them, it seems some of my resistors were burned out. I have replaced the resistors and now the harmonic distortion measurements have gone down dramatically. I'll be doing a follow-up video, but in short the "fuzz" I talk about hearing in this video has disappeared.Corrections:* It seems that 3 db lower is half as much power but not half as much loudness. 10db lower is half as much loudness.Gear discussed:- Amp Camp Preamp+Headphone Amp- AMB Sigma11 power supply- Aune S17 Pro- Xduoo TA-84- Sennheiser HD6XX- ZMF Atrium- Sennheiser HD660S2- Sennheiser HD560S- Hifiman HE5XXSites: DiyAudio.com, DiyAudioStore.com, AMB.orgMentioned:- NitchXSchiit Piety- NitchXSchiit Pietus Maximus- Schiit Mjolnir 3My current chain: Macbook - JDS Labs Synapse - SMSL VMV D2R - Xduoo TA-84 or Aune S17 Pro - Parasound A23+ - Q Acoustics Concept 30 + Paradigm V10 subwooferMusic streamed from either Apple Music or Qobuz0:00 On power supplies6:20 The Amp Camp Pre+12:04 Vs. the S17 Pro15:03 Vs. the Xduoo TA-8419:40 Distortion measurements and explanations26:00 What's next?
This power regenerator completely changed my relationship with my gear Not an Audio Review Channel 2025-05-20 | Got a power regenerator. It changed how I heard both my solid state and tubed gear. I didn't want to hear it, but I did.Correction: while voltage from a mains supply can vary, the 60 hz sine wave should not as that will cause much larger issuesCurrent setup: MacBook - JDS Labs Synapse - Matrix X-SPDIF3 DDC - SMSL VMV D2R - Aune S17 Pro OR Xduoo TA-84 - Q Acoustic Concept 30 OR any number of headphones + Paradigm V10 sub0:00 What will make the most difference to your enjoyment of music0:42 Stuff I tried3:47 What this thing is supposed to do6:37 Is this better than the Mainz8?7:34 How it actually sounds (you'll skip to here but there a bunch of fun stuff you're skipping over)11:08 Surprise ending
Did I find a Transformer Coupled Tube Amp I Liked? (CanJam 2025) Not an Audio Review Channel 2025-03-21 | In my first episode, I said I thought I didn't like transformer coupled tube amps, only OTL tube amps, but I'd find out for sure at CanJam 2025.In this episode, I find out.Correction: in this episode I call the Schiit Valhalla 3 the Valhalla 2Update: I found the secret of the sound that I'm hearing on OTC amps that I don't like, more here; youtu.be/8x8rhs8BhXAStuff mentioned in this episode:* Sennheiser HD6XX headphones* Hiby R6 III DAP* Viva Egoista Belva* Viva Egoista 2a3* Prima Luna Evo 100* Cayin Soul* DNA Supernaut* Feliks Envy Anniversary Edition* Manley Absolute Headphone Amplifier* LTA Velo* Schiit Valhalla 3 (not the Valhalla 2!)* SPL Phonitor XE* Audma GPA-1* Violectric V324* T+A HA200* Enleum Amp-23R* Ferrum Oor* Ferrum Wandla GoldenSound Edition* Mass Kobo 465* Xduoo TA-26S* Xduoo TA-32 (not the TA-33!)* Parker's Associate and battery-powered amp* ETA Ulli headphone* Auribus Sierra and new headphone* Meze EliteMy current main system: MacBook - Matrix X-SPDIF 3 - SMSL VMV D2R - Xduoo TA-84 or Aune S17 Pro - Parasound A23+ - Q Acoustic Concept 30s - Paradigm V10 sub
You Dont Hear Things the Way I Do (on DACs with PecanPi + PecanPi+ vs. SMSL VMV D2R) Not an Audio Review Channel 2025-03-05 | My hearing is weird and things bother me that might not bother you. This is illustrated by my recent demoing of the Orchard Audio PecanPi and PecanPi+ DACs and pitting them against my main SMSL VMV D2R DAC.SBAF Marv (Purr1n) on Treble Fuckery and Harmonic Richness: superbestaudiofriends.org/index.php?threads/schiit-yggdrasil-less-is-more-and-mil-and-og-impressions-measurements.11391/page-5My current main system: MacBook - Matrix X-SPDIF 3 - SMSL VMV D2R - Xduoo TA-84 or Aune S17 Pro - Parasound A23+ - Q Acoustic Concept 30s - Paradigm V10 sub
Is Your Engineering Mindset Lying to You? (Power Cables) Not an Audio Review Channel 2025-02-12 | Surely, this will settle everything forever.Power cables mentioned here: Pine Tree Audio Iso-Braid AC, Cullen Cables Crossover, Wireworld Electra 10, Wireworld Silver ElectraPower conditioner: Ansuz Mainz8 X-TC 3, Furman PST-8My system: Macbook (Qobuz + FLAC files), Matrix X-SPDIF 3 DDC, SMSL VMV D2R, Xduoo TA-84, Aune S17 Pro, Parasound A23+ power amp, Q Acoustic Concept 30 speakers, Paradigm V10 subwooferVideos mentioned here:- Jay’s Iyagi speaker blind test: youtu.be/fcf2tYySyAY?si=GP1tTm9bE3-3M9tR- Jay’s Iyagi GR Research cable blind test: youtu.be/GTwwvY8Is1o?si=-kEtP3_7CXrqRM5l- Passion for Sound on blind testing: youtube.com/watch?v=OZMACL6z3OU- Michael Beeny on the $20 preamp that beats much more expensive gear: youtube.com/watch?v=r8cKlzlzcLI- Chris & Jack, “Body Swap”, youtube.com/watch?v=f7q8f6KMcac- Hans Beekhuysen on power cables: youtube.com/watch?v=5lHPjcXhK4c- Audio illusions: youtube.com/watch?v=kzo45hWXRWU
Hot-rodded cheap monos vs. old school power amp (Fosi V3 Monos + Sparkos SS3602 vs. Parasound A23+) Not an Audio Review Channel 2025-01-29 | Last video I replaced a $2,000 preamp/headphone amp with a $400 one I liked better. Can I do it again with hyped up cheap class D monos hot-rodded with discrete op-amps and replace my $2,000 class A/B power amp? It's the Fosi V3 Monos + Sparkos SS3602 vs. the Parasound A23+My system: Q Acoustic Concept 30 speakers, a MacBook connected to a Matrix X-SPDIF 3 DDC and an SMSL VMV D2R DAC and both an Xduoo TA-84 tube pre and an Aune S17 Pro SS pre. I listen nearfield in a small room.
