Uploaded November 2025 | Updated September 2026, 9 minutes ago
Marshall have arrived at Guitar Summit 2025 with a simple idea. Take the most iconic amps in their history and tweak them until they scare the neighbours all over again.
Find out more from Marshall here - elkqr.link/marshall
Thanks to My Sponsors for their continued support.
Face - elkqr.link/face-gs25
Gravity - elkqr.link/gravity-gs25
Steve walks me through the thinking behind each mod and how Marshall kept the character of the originals while making them far more usable. The 1959 Plexi keeps the traditional volume behaviour but finally gets controllable gain at sane volumes. The two stage clipping gives you diode or transistor based distortion depending on how rude you want it to be. The JCM800 Modified keeps the original voice but adds bypass, Overdrive 1 and Overdrive 2, plus a low end tightening switch for modern tunings and a mid shaping option for extra punch. Even through headphones at a silent show, the differences in feel between gain stages are obvious. These amps react the way old school Marshalls should, just without the punishment.
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DISCLAIMERS
Some of the links in this description are affiliate links. If you purchase gear through these links, I may earn a small commission at no additional cost to you. Thank you for supporting the channel!
All opinions shared in this video are my own and were not reviewed or influenced by any outside parties.
00:00 - Intro: Marshall at Guitar Summit & The New 2025 Modified Series
01:01 - The 1959 Modified: A Classic 100-Watt Plexi
01:35 - 1959 Mod 1: The Bright Cap Switch
02:15 - 1959 Mod 2: Clipping Switch & Gain Flavors (Diode vs. Transistor)
03:31 - 1959 Mod 3: Pre-Tone Stack Master Volume
05:45 - The JCM-800 Modified: Updating an 80s Icon
06:50 - JCM-800 Mods: Overdrive 1 & 2
07:33 - JCM-800 Mods: Tight Switch & Mid-Shift
09:31 - Which Amp is the Favorite?
11:08 - Playing Impressions: Feel, Compression, and "Silent Show" Reality
My Recording Gear
๐ธ๐ค kit.co/theguitargeek/gear-i-use-for-making-videos
๐ธkit.co/theguitargeek/guitar-gear
๐ ๏ธ kit.co/theguitargeek/guitar-repair-and-maintainance
#TheGuitarGeek #marshallamps
Marshall have arrived at Guitar Summit 2025 with a simple idea. Take the most iconic amps in their history and tweak them until they scare the neighbours all over again.
Find out more from Marshall here - elkqr.link/marshall
Thanks to My Sponsors for their continued support.
Face - elkqr.link/face-gs25
Gravity - elkqr.link/gravity-gs25
Steve walks me through the thinking behind each mod and how Marshall kept the character of the originals while making them far more usable. The 1959 Plexi keeps the traditional volume behaviour but finally gets controllable gain at sane volumes. The two stage clipping gives you diode or transistor based distortion depending on how rude you want it to be. The JCM800 Modified keeps the original voice but adds bypass, Overdrive 1 and Overdrive 2, plus a low end tightening switch for modern tunings and a mid shaping option for extra punch. Even through headphones at a silent show, the differences in feel between gain stages are obvious. These amps react the way old school Marshalls should, just without the punishment.
SHOW YOUR SUPPORT FOR THE CHANNEL
๐ค Subscribe for more updates by clicking here - elkqr.link/jdkhn
๐ค Join youtube.com/channel/UCI5i6aBbINMIEkYW3b6olHg/join
๐ค Support the channel on Patreon: patreon.com/AndyGuitarGeek
๐ค Buy something on Reverb - tidd.ly/3YklJqD
DISCLAIMERS
Some of the links in this description are affiliate links. If you purchase gear through these links, I may earn a small commission at no additional cost to you. Thank you for supporting the channel!
All opinions shared in this video are my own and were not reviewed or influenced by any outside parties.
00:00 - Intro: Marshall at Guitar Summit & The New 2025 Modified Series
01:01 - The 1959 Modified: A Classic 100-Watt Plexi
01:35 - 1959 Mod 1: The Bright Cap Switch
02:15 - 1959 Mod 2: Clipping Switch & Gain Flavors (Diode vs. Transistor)
03:31 - 1959 Mod 3: Pre-Tone Stack Master Volume
05:45 - The JCM-800 Modified: Updating an 80s Icon
06:50 - JCM-800 Mods: Overdrive 1 & 2
07:33 - JCM-800 Mods: Tight Switch & Mid-Shift
09:31 - Which Amp is the Favorite?
11:08 - Playing Impressions: Feel, Compression, and "Silent Show" Reality
My Recording Gear
๐ธ๐ค kit.co/theguitargeek/gear-i-use-for-making-videos
๐ธkit.co/theguitargeek/guitar-gear
๐ ๏ธ kit.co/theguitargeek/guitar-repair-and-maintainance
#TheGuitarGeek #marshallamps
