1590a version of the univibe pedal Thomas Hafemann 2018-12-13 | In this video I try to present the different settings of my univibe pedal build.The small switch on the left side activates the vibratto mode. It runs on 12V instead of the 15V used in the original circuit. The lamp was biased accordingly.
Push-pull amplifier using 5672 direct heated tubes Thomas Hafemann 2023-06-11 | In this video I try to show how the subminiature amplifier sounds. It uses 2 5678 tubes in triode mode as preamp, another two for the PI, here a paraphase. There is a post-PI master volume, to get some cleans. Power stage are two 5672 in push-pull with a primary of 32k obtained with a 100V line transformer. Everything runs from two 3.7V LiPo batteries, with the filaments in series and bypassed by 100uF capacitors, to reduce feedback between stages. To bias the output stage a ICL7660 was used. The 5672 pair is biased between -11V and -12V. Check the instructable for the schematic and layout.
1W push-pull amplifier with 12AU7 Thomas Hafemann 2022-05-12 | In this video I tried to demo the 1W push-pull amplifier inspired on the OR120. It has 6dB of negative feedback as in the original design.
5762 subminiature amplifier powered by batteries, test 2 Thomas Hafemann 2022-03-27 | I made some slight changes to reduce the preamp gain. The preamp will never distort in this amplifier anyway. All the distortion comes from the paraphase PI (without feedback, not unity gain) and the power stage. More info at:https://www.diyaudio.com/community/threads/bassman-micro-5672-subminiature-pp-build.371474/page-4
5672 subminiature amplifier Push-Pull powered by batteries Thomas Hafemann 2022-03-24 | First test of another subminiature amplifier powered by LiPo batteries.First two stages are 5678 tubes in triode operation, followed by a paraphase phase splitter composed of two 5678 in triode mode, followed by two 5672 tubes in push-pull configuration. Transformer is set up to reflect a 31k primary connected to a cheap 4", 8 ohm speaker. The noise in the beginning (bees or wasps) comes from the unshielded MAX1771 SMPS and the rats nest build style I am using. It also uses another ICL7660S SMPS to produce the -6V used for the bias. Everything powered with 2x3.6v LiPo batteries. The filaments are in series, and the ICL7660S provides different taps for grid biasing the stages. Bias of the 5678 stages is roughly at -1.5v, while the 5672 are at -12v. As seen in the video, with the volume (between 1st and 2nd stages) at 10 o'clock the output stage is starting to distort. Anything above that and it gets distorted pretty fast. At 2 o'clock it already sounds like a fuzz.
External tap tempo and analog delay clock Thomas Hafemann 2021-12-15 | This pedal uses the MV-64 chip (delaytion) to add functions such as tap tempo, modulation and settings storage for the use in combination with an analog delay. For the video I am using a circuit similar to the DMM developed over madbeanpedals (dirt bag). In this video I try to demonstrate how it works. And what are some capabilities of the controller. Some of the settings are kind of weird and would require some adjustment.
Small analog delay with 2xMN3005 (dirt bag inspired) in a 1590LB Thomas Hafemann 2021-12-15 | Another build of an analog delay in the 1590LB box. Is is inspired on the dirt bag that was available at madbeanpedals, which is similar to the deluxe memory man, with 2 MN3005, running at +15V (no weird power supply necessary).It has an additional clock input (3.5 mm jack) which bypasses the internal LFO. In this way any clock signal (10kHz to 200kHz square wave) can be used to control the internal CD4047 IC, which drives the two BBD chips. Most of the difficulty here was in fitting everything in the small 1590LB box. For the video I am using a single-ended custom build tube amplifier, with an 12AX7 in the preamp and the EL84 in the power stage. The internal speaker is the rather small 6 inches Jensen alnico. I play it mostly clean, to demonstrate the BBD delay.
12AX7-12AU7 SE tube amplifier Thomas Hafemann 2020-04-25 | Low wattage (0.4W) tube amplifier with three gain stages and one 12AU7 triode as power stage. Slightly different from a previous build, with the tone control after the three gain stages. Voltage is also a little lower at 200V. Not much clean (unless you use the guitar volume) headroom, but ideal for that distorted tube sound. Less noisy too. By running at lower voltage and with a 47uH inductor I managed to remove any noise from the MAX1771 SMPS. It runs from a 12V 1A PS, here even a switched PS without any heterodyning.
Hollis Ultra flanger with the V3207 Thomas Hafemann 2020-04-16 | This is a smaller version of the ultra flanger in a 1590LB box. Instead of the commonly used MN3007, it was adapted to run with the much cheaper V3207. Short overview of the effect, from flanger to chorus just tweaking the manual. This one is a nice flanger, with some distortion you can get that jet like sound, but also a nice chorus like sound. Recorded it with the mic of the camera, so that some string buzz is still audible in the background.
v3205 9V deluxe memory man diy vs. moded economy memory man Thomas Hafemann 2019-11-19 | I added an additional BBD to the economy memory man I had built earlier. Here I try to compare both at the new maximum time delay. The economy memory man is much darker, but as a result has much lower clock frequencies and longer delay time.The dmm clone still sounds better, it is much brighter and colored.
V3205 BBD analog delay based on the Dirtbag (9v Deluxe Memory Man) Thomas Hafemann 2019-10-22 | Video of my 9V build of the Dirtbag using a homemade PCB. I'm playing an SG with humbuckers, both pickups, with both volumes at half to avoid the distortion of the repeats. The overload LED barely blinks.The schematic is the Dirtbag, from Madbeans, with the Mods for the v3205 BBDs. The PCB was etched at home. This was my first attempt of mixing SMD components with through hole components (BBDs and SA570). Level was kept at 12 o'clock for a comparable output with the true bypass, and the blend control was at 1 o'clock for a slight louder first repeat.
BBD analog delay with V3205 Thomas Hafemann 2019-07-11 | I started from the economy memory man circuit, which used the MN3005 BBD and run with a -15v+15v power supply and had the chorus switch (blue big box). This, on the other hand, runs on a single 9V power supply, with the easier to find v3205 BBD. Instead of the using the clock with the 4047 I used a V3102, without the LFO, so it has no chorus effect. The boost is always on, but instead of a 12dB boost it has just enough to have unity gain with the blend potentiometer centered. The original had a slight volume drop when the blend is at the center. What I really like in this is that I could fit it inside a 1590LB. There is still room for improvement. The economy memory man is not known for a long delay. By adjusting a trimmer in parallel with a 1MA potentiometer I could get more time out of it before the clock started to bleed through. The max. value is now at 155k, against 100k of the original, so a slighly longer delay.
Mini flanger based on the Electric Mistress Thomas Hafemann 2019-04-24 | This circuit is a mix of the ultraflanger (clock) and the electric mistress (audio path). It has the manual control of the ultraflanger but is also less noisy. On the other hand, there is no way to get the jet like flange achieved with the ultraflanger.
High gain amplifier using subminiature tubes Thomas Hafemann 2019-03-16 | In this video I try to demonstrate some of the settings of my latest build, a high gain subminiature amplifier. The amplifier uses five 5678 tubes in the preamp, followed by a 5672 in the output stage. The output transformer is a 22k reverb transformer. The amplifier runs from a 9V power supply. All filaments are in series, to reduce the required current and the plate voltage is obtained using a 555 SMPS, which delivers 70V to the first RC node. The clean switch bypasses 3 stages, been only affected by the master volume and the presence control. It is very sensitive to the guitar's volume. It can go from overdriven tones to high gain with lots of sustain. It even feedbacks on some settings.Everything packed in a single 1590B box.
DIY Dual PT2399 delay based on multiplex Thomas Hafemann 2019-02-28 | Here I'm demoing my latest build, a dual PT2399 delay in a 1590a enclosure! The schematic is based on the multiplex delay, but with only two positions: series or parallel.In series mode I can achieve longer delay times or weird effects when combining shorter with longer delays. In parallel mode both chips give different delay echoes, making this a nice configuration to achieve some reverb sounds. Playing on the verge of oscillation gives almost a shimmering sound.But it can also get those crazy oscillations used in some songs. I like to let it oscillate and play with the delay times to change the pitch. More info you find here: http://www.madbeanpedals.com/forum/index.php?topic=29359.msg284455#msg284455PS. It can get loud when oscillating, the camera mic distorted a little bit.
Octave up sick box (OUSB) pedal test Thomas Hafemann 2019-02-20 | Playing the octave up pedal with the neck pickup.The octave up sick box is also a nice fuzz.
High gain subminiature amplifier first attempt: preamp Thomas Hafemann 2018-12-18 | I started to test the possibility of building a high gain, mesa style, subminiature tube amplifier. Here I'm testing the preamp stage, it still requires some better biasing, much more difficult when you're using DHT pentodes.All the tubes are 5678 pentodes. Here I'm using them in triode mode at only 45V. The sound is still too bass heavy and fizzy, but with some adjustment I think it's possible.
12AU7 tremolo in Vox Escort small combo Thomas Hafemann 2018-10-08 | Solidstate to tube amplifier conversion of a Vox Escort.I used an AC4 inspired circuit, with the EF86 preamp, the modified 5-stage 12AU7 tremolo circuit and an EL95 SE power stage. I kept the original speaker and some other parts from the Escort. Here I show different speed settings for this unusual tremolo circuit. The tremolo control is now where the older battery-mains switch was. The tremolo can be deactivated by using a footswitch or by setting the max. speed setting.More Info available at:https://www.diyaudio.com/forums/instruments-and-amps/328412-tremolo-12au7.html
Tube amplifier powered with Li-Ion batteries Thomas Hafemann 2018-08-15 | The amplifier uses 2 Li-ion batteries combined with a MAX1771 SMPS to supply 6 russian subminiature tubes. The series filament string current is just 37 mA.The preamp is composed by two 1J24B pentodes, followed by a paraphase PI also using two 1J24B tubes in triode mode. The power stage has two 1J29B tubes in push-pull with a 100V line transformer as the output. I'm using the 0, 0.625w taps for the plates and the 2.5w tap as the center tap. The voltage at the CT is 110V with the batteries fully charged and falls to 85V with the batteries almost discharged.I'm using a 4" speaker inside this small 180x180x80mm wooden box, previously used as an ammeter. I tried to show some different gain settings in this video. When the volume is maxed there is a fuzzy kind of distortion. This was intentional, to have some extra distortion and feedback. The output is only 0.3W, but don't let that fool yourself! That is really loud for a living room. More info at:http://www.diyaudio.com/forums/instruments-and-amps/324149-russian-rod-tubes-battery-tube-mini-amplifier-prototype.html
Tube amp using only DM160 magic eye tubes Thomas Hafemann 2018-07-14 | This was only a small test, not a proper amplifier, still would need some improvements. I just compared how much one can get from this tubes in Parallel Single-Ended (PSE) or self-split push-pull (SPP). The SPP configuration still requires some changes. By changing the bias I could increase the output a little bit, so that it would be at least as loud as the PSE.DM160 preamp with 100k to 1M gain pot to second DM160 stage. From there to the power tubes. In the SPP the signal goes to the output tube through the cathodes (also the filaments). By adding some bypass caps from f+ to f- I managed to increase the output.As shown in the oscilloscope, the max. power is around 2mW (lol).This is good enough for apart. after midnight, and swap the greenback for a headphone and it rocks.
1J29-b and 1J24-b push-pull amplifier Test Thomas Hafemann 2018-06-20 | Here I'm using a 4" speaker, over the table, without cab.Small tube amplifier running on two 3.7V batteries.The SMPS is based on the MAX1771 chip, delivering 100V with 7.4V at the input.3 gain stages using the 1J24-b, also called 1SH24-b, in pentode configuration, followed by a suppressor grid driven PI. The anode and screen are 180 degrees out of phase in this case, and the grid is at 3.3V. The power stage is based on two 1j29-b or 1SH29-b tubes and a cheap 100V, 10W line transformer, using the 0.625w tap, which gives 29k from anode to anode. The filaments are in series, and add up to 4.8V at 32mA. A Schematic can be found here:https://i.imgur.com/n74daapl.png
Testing 10w tube amp with ecl82 Thomas Hafemann 2018-06-12 | The power amplifier consist of two ECL82 in PP configuration. The preamp is based on the jcm800, with 2x 12AX7, Handmade mahogany cab, with a single greenback 10".Gain is maxed, and volume at minimum and it's still too loud.Recorded with the mic of the camera.
Push-Pull Subminiature tube Amplifier with the 5672 tube Thomas Hafemann 2017-12-27 | Quick video of the subminiature amplifier based on the liverpool/AC30 top boost preamp. Amp. volume was maxed, while I play with the guitar volume to get the clean sound. Camera is a Nikon d5300 and I'm using the built in microphone.More information available at diystompboxeshttp://www.diystompboxes.com/smfforum/index.php?topic=79544.msg1113625#msg1113625
Loophole looper pedal with vibrato mod Thomas Hafemann 2017-11-24 | Based on the loophole pedal, with an added LFO for the vibrato mode. This pedal uses the ISD2560 recording chip to create a Lo-Fi looper. It sounds nice with the vibrato add-on. Unfortunately the recording was made with my phone, sitting on the amplifier with a lower volume setting and my bad playing&stomping skills.
Lowrider pedal build Thomas Hafemann 2017-11-11 | Here a short video testing the lowrider pedal, available at madbeans. It has two octaves down and one up. The octave up can be dialed with a trimmer to sound like a fuzz, like in the video. More info at madbeanpedals
Inductorless Wahwah Thomas Hafemann 2017-08-21 | I built this pedal in a 1590a box and it really sounds nice, better than my other inductorless wah from colorsound. Because of the size of it there is a learning curve to master this pedal.Thanks to the guy over http://cackleberrypines.net/transmogrifox/TransmogriNotes/skwah/for all the simulations, the analysis and for making the schematic available.
ECL86 lunchbox amplifier Thomas Hafemann 2017-06-26 | This amplifier was built using only an ECL86 tube in a small lunch box. This amplifier has a small power transformer to deliver the 260v. It has a 4 inches speaker, and the box is sealed.
Subminiature tube Amplifier, low wattage. Thomas Hafemann 2017-02-07 | Another subminiature tube amplifier, using 6111 and 6112 tubes.OT has an impedance of 22.5k, PP, running at 214 v. The 6111 is biased a little colder, to keep the volume down. The preamp has plenty of signal to push it into distortion anyway.The speaker is a simple 4" radio speaker, 3w. The shinny object visible through the grill cloth is the dust cap. The box has only 16.5x12.5x8 cm, made of 6 mm plywood and with real tolex.It uses a max1771 SMPS to multiple the 12v 2A input to 214v at the OT. The video was made with a nikkon camera and the built in microphone and a gibson sg 60's tribute straight to the amplifier input.This is a DIY project, with all information available at madbeanpedals.com/forum, diystompboxes.com/smfforum and Handmades.com.br.Thanks to all the guys that helped me on this project.
modified green ringer Thomas Hafemann 2016-12-13 | Green ringer with another transistor in the front and a light controlled intensity effect.
Russian miniature tube amplifier Thomas Hafemann 2015-09-23 | Maxed volume for some power tube distortion.As the video shows, the noise floor also increases.
Russian Subminiature tube amplifier Thomas Hafemann 2015-09-22 | This amplifier uses 3 subminiature tubes, 6n17B in the preamp and PI and 6n16b in the power amp. The controls are gain (with bright cap), tone (the trebble setting in a regular tonestack) and a master volume.This clip sounds a little too bright to me, it sounded better live though.I'm using a 60's tribute gibson and a celestion greenback in a 1x12 cab (open back).
Russian Subminiature tube guitar amplifier Thomas Hafemann 2015-06-11 | This amplifier is similar to recent low wattage amps that use a cathodyne as a PI. The preamp and PI tubes are 6n17b, and the power stage is a 6n16b in push-pull, with a 22.5K output transformer. SMPS is delivering 234V. The controls are gain, treble and volume;It's my new prototype to fit in a 1590b box. I'm playing a LP through a 1x12 loaded with a greenback.
Mini PCL84 one tube amplifier Thomas Hafemann 2015-04-14 | This amplifier was build in a 1590a box, with a MAX771 SMPS delivering 225V to HV.It has aprox. 0.5W an that's loud enough to play in a apartment.The art was made by etching, and follow a vintage pattern. The Output transformer is a 220v-6V PT that was adapted. In this video I try to show how it sounds, but i guess the camera is clipping the sound. It has a lot of bass, and increasing volume gives a slight overdrive, but has this loose bass.
Mini WahWah, based on colorsound inductorless Thomas Hafemann 2015-04-02 | Hi guys,here is the video for this small wahwah that I made, sorry for the bad riffs, I really need to practice some guitar and stop building things!Well it's small, enclosure is a 1590a. It's easy to build, just look for any inductorless colorsound wah. It works with a LED/LDR combination and a plastic shutter.I made an egyptian etch, becaus I like it! Unfortunatelly these is just a common vector image, and means nothing (I think)..(if I new hieroglyphics I would write..."the one that build the tiny wah, but has a big foot", but I guess there is no such thing for wah)Hope you like it!Take a look at Madbean, or Diystompboxes or Handmades and search for the picture tutorial!
Vibratone Subminiature tubes amplifier Thomas Hafemann 2015-03-12 | Comparison between small 3" speaker and big 12" celestion greenback.A lot more volume and better tone with the bigger one. Still a nice low wattage amplifier.Recorded the audio and video with the nikon d5300. Playing a gibson tribute 60's.For more information:http://www.diystompboxes.com/smfforum/index.php?topic=83831.0
12ax7 12au7 SE tube amplifier Thomas Hafemann 2015-03-12 | Small amplifier, runs with 12V.An internal SMPS delivers 200V for the tubes. OT is a fender reverb 3w transformer.Guitar is a gibson tribute 60's, bridge pickup.Speaker is a Celestion 12" greenback, and mic from a d5300 nikon.
Subminiature Tube Amplifier based on JCM800 Thomas Hafemann 2015-03-12 | Small practice amplifier, with russian subminiature tubes, based on JCM800 schematic. It uses a SMPS to deliver 200V from a 12V 2A power supply. Here is a comparison of the sound using the stock computer speakers and a Celestion Greenback with a Gibson LP 60'tribute 2013, bridge pickup. As the output stage is too sensitive, I also adjust the guitar volume to obtain a cleaner sound. Bright cap is always on.Sorry for my bad playing skills.The video was made with a Nikon D5300, with the camera mic.http://www.madbeanpedals.com/forum/index.php?topic=248.75http://www.diystompboxes.com/smfforum/index.php?topic=79544.0http://www.handmades.com.br/forum/index.php?topic=6627.0http://www.freestompboxes.org/viewtopic.php?f=28&t=12195&start=40
Subminiature tube amplifier with tremolo Thomas Hafemann 2014-12-28 | This project was introduced by Frequency Central at diystompboxes, and is called "Vibratone". I Just made a small combo of it.It uses a 3" speaker and was filmed with the camera mic. from the back. It has a speaker output for bigger speakers. But it's loud enough to play at home at night. Headroom is very reduced though. It only exist with a bigger speaker or headphone.If you're interested take a look at:http://www.diystompboxes.com/smfforum/index.php?topic=83831.0
Submini tube combo Thomas Hafemann 2014-12-14 | All tube subminiature amplifier using russian double triodes, based on jcm800
Russian Superfly Submini Tube Amp in a 1590a box Thomas Hafemann 2014-05-12 | Subminiature tube amp based on Frequency Central's superfly circuit using the MAX1771 SMPS.Based on Perrow's (from DiYstompboxes) 1590a approach for the Superfly I decided to make a new board using the MAX1771 SMPS.The Superfly schematic was adapted for the use of the 6N17B and 6N16B submini russian tubes. Everything was shared here:http://www.diystompboxes.com/smfforum/index.php?topic=78302.msg972714#msg972714Cheers, Thomas
12ax7 12au7 SE Amp Thomas Hafemann 2014-02-21 | Based on Frequency Central's Obsession amp, I made this, using same Max1771 SMPS and Fender Reverb Transformer.Running a 12ax7 and a 12au7 in SE.Using the Meteoro Thor speaker and a 60's tribute LP.Recorded with cellphone camera.
Submini JCM800 Thomas Hafemann 2013-10-29 | Subminiature version of the Jcm800 circuit, using russian subminiature tubes, 6N17B and 6N16B.12 to 200V SMPS, based on FrequencyCentral Max1771 circuit.Power amp based on Dmitry's 5-tube push-pull Fender derivative amp, with LTP PI.Preamp uses same schematic as Jcm800 2203.PTP wiring and old pc speakers.Guitar is an Epiphone LP Standard
Submini JCM800 amp Thomas Hafemann 2013-10-29 | Subminiature version of the Jcm800 circuit, using russian subminiature tubes, 6N17B and 6N16B.12 to 200V SMPS, based on FrequencyCentral Max1771 circuit.Power amp based on Dmitry's 5-tube push-pull Fender derivative amp, with LTP PI.Preamp uses same schematic as Jcm800 2203.PTP wiring and old pc speakers.
Subminiature JCM800 with 12V SMPS Thomas Hafemann 2013-10-29 | Subminiature version of the Jcm800 circuit, using russian subminiature tubes, 6N17B and 6N16B.12 to 200V SMPS, based on FrequencyCentral Max1771 circuit.Power amp based on Dmitry's 5-tube push-pull Fender derivative amp, with LTP PI.Preamp uses same schematic as Jcm800 2203.PTP wiring and old pc speakers.
