Brit 800 2204 vs 2203 thoughts

@LiamH metal toggle was canadian version.
rocker switches came in around 77, I have a 76/77 Super Bass with bat wing toggles and a 1977 JMP2203 with rockers. A few videos of my 2203 and 2204’s







Some boosted tones of the 2150 - I actually tended to use it more as a Plexi style amp which it is probably better suited for. Does high gain better than a 1959 though IMO.



 
Just quickly chiming in to say this is already by far my favourite thread on these forums in the past 10+ years. I have to admit I can’t even read amp schematics well but what a goldmine this thread has been so far. Keep it coming 🫡

Could someone explain the sonic differences between cascaded vs separate preamp tube inputs like I’m a five year old? Does it affect just the gain or something more? Did this change in 2203 JMP at some point?

EDIT: I also will have to let a band that I’m working with know about the horizontal input JCM I sold to their guitar player. He’s been using a re-issue Silver Jubilee now and let the JCM gather dust, but maybe modding his amp to the early 80’s style might change things.
EDIT2: just figured out the JCM I was talking about is a 2203 and those same mods do not apply for it as far as I understood.
 
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Aens, there's probably people who could describe this better than me, but I'll give it a shot.

In amps like the original Plexi 50w (model 1987) and 100w (model 1959) as well as the very early JMP 2204, there were 4 inputs: 2 normal channel and 2 high-treble channel. This is like the Fender Tweed amps like the 5F6A Bassman that Marshall used as the inspiration of their amps. You could choose to play through either channel or "jump" the channels by plugging into both. After this first stage, the channels were mixed internally by a second stage. When jumped, you can control the relative amounts of "edge" and "body" by setting each channel's volume control differently. This is different than what the tone controls do and allows you do to some rough tone shaping.

In amps like the 2203 and later 2204, there are 2 inputs, both feeding the same channel. Since there was a tube that was no longer being used for a second channel, Marshall put this tube in between the input and the tone controls, "cascading" the signal from one through the next. This adds more gain to the amp, which is usually used to add more overdrive to the signal but doesn't always do so. (As an aside, Fender did the same thing in the Blackface Reverb amps where the extra tube is used to boost the signal after the reverb (gain) but doesn't add any appreciable distortion. This is one of the reasons some players say the reverb channel on these amps sounds thicker or have more body.)

On other words, in a Plexi, there is a single gain stage, followed by a mixer stage, followed by the tone stack. In a 2203, there are two gain stages, followed by a mixer stage, followed by the tone stack. While the 2203 is capable of more gain (technically), it is important to remember that gain does not equal distortion. Gain is simply how much the original signal is amplified, while distortion occurs when any gain stage is driven over its limits.

The tonal result is that, the more gain stages the signal is passed through, the more overtones are added, depending in large part on how the volume controls are set and what other circuitry exists between the stages. This may or may not add to the apparent distortion present in the signal, but does give more stages for the signal to be pushed close or over the limits of the next stage. This is one reason why many players prefer edge of breakup sounds to very clean sounds which can end up sounding somewhat sterile. Of course, the signal can be pushed over the limits of even a single gain stage (like high output pickups, boosts, and drive pedals do), so just because one amp may have fewer gain stages than another, they both may be capable of great levels of distortion. And, since we're only talking about pre-amps here, there is still the power amp and that's also a gain stage (although a different kind), and a single pre-amp stage can overdrive a power amp (like a Fender Champ, for instance).

Amps like the 2150 are interesting because they have both two channels, like a Plexi, and an additional gain stage (and master volume), like a 2203. Kind of a best-of-both-worlds, at least on paper. And early 2204s were much closer to the Plexi circuit than the 2203 ever was (the 2203 only ever had cascading gain stages).

None of this touches on the master volumes that the 2203 and 2204 have. It's safe to think of this master volume simply as another volume control in the pre-amp, since this is where they are located in these circuits. This is different than a post-phase-inverter master volume, which is in the power amp. For example, you can add a master volume to a Plexi or use the master volume in the Plexi models, but it'll still sound like a Plexi.

Anyway, I know this is a very over-simplified explanation and leaves out a lot of details (pre-amp voltages and dropping resistors, etc.) and I'm sure others can explain this better than I can, but I hope it helps at least a little.
 
Just quickly chiming in to say this is already by far my favourite thread on these forums in the past 10+ years. I have to admit I can’t even read amp schematics but what a goldmine this thread has been so far. Keep it coming 🫡
:D... Me too (except I can read schematics, and have modded and repaired a lot of Marshalls over the last 30 years). I Got my first Axe FX in 2016, and I've been waiting quite patiently for this moment to come!
Could someone explain the sonic differences between cascaded vs separate preamp tube inputs like I’m a five year old? Does it affect just the gain or something more? Did this change in 2203 JMP at some point?
2203 was always cascaded, but the early 2204 had separate inputs. The difference is pretty stark. The separate inputs version is effectively a 50 watt model 1987 with master volume, and a choice of 2 different input gain stages. Cascaded gain stages takes the output from the first gain stage, and injects it into the second, giving a whole lot more availability of overall gain. Plug into the low input of a 1980 2204, or any 2203 to give an idea of the sounds without re-amplifying the input gain stage. (Although maybe slightly lamer, you'll need to crank the preamp).
EDIT: I also will have to let a band that I’m working with know about the horizontal input JCM I sold to their guitar player. He’s been using a re-issue Silver Jubilee now and let the JCM gather dust, but maybe modding his amp to the early 80’s style might change things.
EDIT2: just figured out the JCM I was talking about is a 2203 and those same mods do not apply for it as far as I understood.
The mods still apply, although they are slightly different for the 2203, and you might need to add another filter cap to make it sound like a vertical input 2203. But either way, they don't sound good stock, and from what I can see in the schematics, and from watching that video, some of those mods could still be applied very easily. It seems there were 2 versions of the filtering arrangement in the horizontal input 2203, so there's some chance it could be changed to earlier spec without making any new holes in the chassis. It could definitely do more than gather dust!

@LiamH metal toggle was canadian version.

As @MirrorProfiles says, we had toggle switches in the UK/US too, but normally plastic. My first experience of a 2203 was recording a demo single in the mid '90s, when the producer turned up with a Marshall JMP 2203 with toggle switches for me to play through. It was life changing! I don't know if it was a Canadian one, or a very early UK one. Either way, I'm not sure any of the 2203s I have owned since have completely lived up to that experience. I've never seen another one the same since, but I do keep an eye on Ebay and Reverb just in case. In my failing memory, it was metal toggles, but I'm not certain of that.

I used a Marshall 2203 for almost every rock gig I played for about 20 years after that, mainly using a 1980 model that I bought as soon as I could find one after that (and I still have that one). Experimented with a Hiwatt Custom 100, had a year or two dalliance with a 100 watt Matamp head and 4x12. I also tried a few "channel switchers", but until I found Fractal, I always ended up back using a Marshall 2203. There's just something visceral about them that nothing really replaces. The Axe FX II was the first thing I found that could even nearly substitute, and I think it now goes a little way beyond nearly just recently.

Liam
 
Just as aside, I remember the first time I ever played through a Marshall... and I hated it! I remember thinking, "this is it???" Of course, I had absolutely no idea what I was doing with it, but I held a grudge for years even though I grew up on the sound of modified Marshalls. I gave the other guitarist in the band I was in at the time all sorts of hell for his Marshall (a Valvestate), too. Then... I learned. Like Liam, I keep coming back to my 2203 and the recent updates to the Marshalls in Fractal have gotten me addicted all over again. I've been bouncing back and forth between the Plexi 6550, Brit Silver, and the Brit 800s since the last update came out. I visit others, but just seem to end up back there lately. No complaints at all!!
 
@Churchhill @LiamH or anyone else in this thread: I’m gonna offer you the whole evening in a bar if we ever meet in person. Much appreciated.

Prior to 2012 when I bought my first Fractal had only been playing with modern solid state Marshall’s. Was not impressed, after Fractal Marshall was all I've been playing. Bought my first late 80’s JCM 2203 back in 2019 and managed to match it with the Brit 800 model pretty easily, so didn’t end up spending much time with it. Covid times were financially rough so my friend bought it from me as ”Marshall aid”. In early 2022 I bought my first JMP 2203 (’81) from Reverb for 1500€ (should be pretty much stock with Marshall factory tubes still inside), but I suppose the power tubes need to be changed as they don’t sound healthy if you crank up the master volume. I guess the previous owner did not have the heart to turn up the master above 3.

It was only beginning of 2023 when I had the chance to really crank up a JMP 2203 with a guitar I’ve only ever dreamed of ever playing or even seeing, which used to belong to my #1 guitar hero. The pedalboard was also 1:1 replica of his original one. He passed away tragically almost 30 years ago and almost all of his gear has been lost until recently. Playing a 2203 LOUD was a life changing experience and I can’t believe how much of the fun I’ve been missing out. Also playing that particular guitar that I thought I've never have a chance to play also made it a once in a lifetime experience. I’ve never been so excited in my lifetime and couldn’t sleep for a week when I found out I had this chance coming.

Not me in the picture, but this is the only one showing the whole gear used (sorry Kimmo 😘).

IMG_1236.jpeg

One of the most unique guitar sounds I've ever heard coming from a 2203 JMP ('78) and Les Paul Deluxe (mid-late 70's). The serial number of this particular amp in the video below has even been traced (#99819K), but the amp has not surfaced yet. Here's some raw 2203 power:
 
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Playing a 2203 LOUD was a life changing experience and I can’t believe how much of the fun I’ve been missing out. Also playing that particular guitar that I thought I've never have a chance to play also made it a once in a lifetime experience. I’ve never been so excited in my lifetime and couldn’t sleep for a week when I found out I had this chance coming.

@aens - I love it when anyone gets excited about playing and your excitement just shines through! That's so awesome!

Yeah, playing a cranked Marshall is a life changing experience! I love being able to get all these sounds out of my Fractal at any volume I need, but I equally love just plugging straight into my 2203 and a 4x12 and feeling the whole universe shake!

One of the things I really like about the 2204/2203 is the ability to really balance the amount of pre-amp and power-amp distortion. It's not an over-the-top amount of pre-amp drive like most Boogies and other "modern" high-gain amps, but you can get more (or less) pre-amp drive than a Plexi if you want it or need it to balance how much the pickup is driving the input. One of the first things I do, either with an actual Marshall or in my AFX, is set the pre-amp volume fairly low (maybe 3-4) and then turn the master up to where the power-amp is starting to cook (usually around 4 or so, then adjust the pre-amp to get the amount of drive I want. Tweaking the tone stack is usually one of the last things I do, but again, this is just me. With a Marshall, this can get REALLY LOUD, but, OH, MAN, WHAT A FEELING!!

Just such an amazing time to be a guitarist, so many incredible tools. So, yeah, next time we run into each other, we can both buy a round, one for Cliff, one for Jim, and maybe a third for Leo ('cuz a cranked Bassman is where so much of this really started).

And that video, that is a GREAT sound... going to watch more of that later this evening. So good! Thanks for sharing that!!
 
@Churchhill @LiamH or anyone else in this thread: I’m gonna offer you the whole evening in a bar if we ever meet in person. Much appreciated.
@aens, just a pleasure to share with a fellow enthusiast. I haven't done a whole evening in a bar with Finnish people for some time, last time was really hardcore. I fear I might be a bit too old to do the occasion justice nowadays. Let's hope I get the opportunity to fail at it one day!
It was only beginning of 2023 when I had the chance to really crank up a JMP 2203 with a guitar I’ve only ever dreamed of ever playing or even seeing, which used to belong to my #1 guitar hero. The pedalboard was also 1:1 replica of his original one. He passed away tragically almost 30 years ago and almost all of his gear has been lost until recently. Playing a 2203 LOUD was a life changing experience and I can’t believe how much of the fun I’ve been missing out.
Looking at the photo, there are a few of the effects that I always feel bring out the best in the 2203. They are not a purist's valve tone amp as much as a filthy pedal platform for me. Classic 70s and 80's phasers and flangers driven by some of the classic dirt pedals of the era never sounded better than into a 2203. Small Stone, Small Clone, Deluxe Electric Mistress, and then TS for clarity, and Big Muff variants for absolutely huge textures. And of course some delay. I used a WEM Copicat Mk III tape echo most of the time, occasionally a Roland RE-201, but the WEM somehow suited the 2203 best. I've generally favoured a good Les Paul, but had many years of using my 2203 with a Telecaster fitted with a Gibson 490T Humbucker in the bridge position. Should have kept that guitar, it sounded pretty special!
One of the most unique guitar sounds I've ever heard coming from a 2203 JMP ('78) and Les Paul Deluxe (mid-late 70's). The serial number of this particular amp in the video below has even been traced (#99819K), but the amp has not surfaced yet. Here's some raw 2203 power:

OK, now THAT is exactly what I think the 2203 is most completely suited to. @aens, I'm guessing as a fan you might have been in the same room as that sound back in the day? If you were, tell me this: is there any recording in the world that has replicated a live 2203 with a great player in full flight? I'm listening to that, and imagining what it must have sounded and felt like in the room. If I'd never experienced similar, I'd be reading this and just thinking it was the ravings of a madman. But you know it isn't, right? 🤣

Liam
 
If I'd never experienced similar, I'd be reading this and just thinking it was the ravings of a madman. But you know it isn't, right? 🤣

And to think I felt a little crazy trying to figure out what flanger he was using... 🤣 I love that, though! Just enough to give it a little movement but not even close to being overwhelming. Can't even really tell it's on until he holds a chord.

Small Stone, Small Clone, Deluxe Electric Mistress, and then TS for clarity, and Big Muff variants for absolutely huge textures. And of course some delay. I used a WEM Copicat Mk III tape echo most of the time, occasionally a Roland RE-201, but the WEM somehow suited the 2203 best.

Yep, here, too. With the 2203 (really Marshalls in general), I've also really enjoyed the MXR pedals, Phase 45, Phase 90, Flanger, Micro Amp, Stereo Chorus. The MXR Analog Delay was one of my favorites, too, and the Maestro Echoplex. Those WEM Copicats are great, too! I'd add the ProCo Rat and even the Boss DS-1, OD-1, and CE-2.

The way you described the 2203 as a "filthy pedal platform" is just perfect. It doesn't need them, but it works so well with those late '70s and early '80s pedals. Get the power-amp hot and the effects just become part of the sound in a really unique way.
 
Small Stone, Small Clone, Deluxe Electric Mistress, and then TS for clarity, and Big Muff variants for absolutely huge textures. And of course some delay.
Small Stone (V2) with 2203 is IMHO the best phaser sound one can ever wish for. The re-issue just blows. Also that DOD Performer flanger is just pure magic as no other flanger I've played produces a feedback like it. Too bad there are not many around to stock up. Also TS has been my go to drive pedal for 10 years with Marshalls. I have quite succesfully replicated all but the Performer flanger to my Fractal if you want to try that same pedalboard pictured above with your Fractal. Deluxe Big Muff is a tough one because it's noisy as hell, but I've managed to somewhat match at least some of the settings. Should get mine modded asap and try to match it after that.

OK, now THAT is exactly what I think the 2203 is most completely suited to. @aens, I'm guessing as a fan you might have been in the same room as that sound back in the day?
Sadly I wasn't. I was 2-4 years old when those albums came out, so I never got to see the band live. They quit in 1995 and shortly after their frontman died tragically. Though recently I do have access (by request) to their album tracks, so I'd kind of call that as close as possible of being in the same room.

If you were, tell me this: is there any recording in the world that has replicated a live 2203 with a great player in full flight? I'm listening to that, and imagining what it must have sounded and felt like in the room. If I'd never experienced similar, I'd be reading this and just thinking it was the ravings of a madman. But you know it isn't, right? 🤣

Liam
I've been trying to keep my mouth shut about this stuff here for 10 years since over 99% of the people don't give a shit, but only recently posted some of it here. I finally feel like this is a safe space enough, thanks to you 😅

Every single Kingston Wall song is live 2203. Perfect example how versatile that amp is with a great player. Every album has been recorded live on tape in studio and played with the same '78 JMP 2203, late 80's 1960B cab with 8 ohm G12T75's, same Les Paul and those pedals in the picture above. That's the reason I've been asking for a 2203 JMP amp model for years. Guitar amp and cab were put in a hallway with a stone floor because the amp was painstakingly loud. One close mic, one in ~3 meters and one in 5-6 m. This is the sound I've been chasing for 10+ years gathering information from low quality live videos and trebly 90's album mixes, and I finally should be there soon enough. That is kind of my personal EVH sound a lot of people try to chase for years.

Here's a 2023 mix of a track recorded studio live on tape in 1992. First take of the album session and only one take while standing, singing demo vocals and guiding the rest of the band like a total madman. Only those glissando guitars are overdubs. Still completely blows my mind. One of the best live guitar takes ever recorded if you ask me:
 
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And to think I felt a little crazy trying to figure out what flanger he was using... 🤣 I love that, though! Just enough to give it a little movement but not even close to being overwhelming. Can't even really tell it's on until he holds a chord.
That flanger IS special!! And well... I've been zooming in low quality Youtube videos for years and spending stupid amounts of money on completely wrong purchases. Gladly the original board was finally found almost 2 years ago laying in some guy's garage and those pedals were 100 % confirmed. Only TS808, Small Stone and Crybaby were missing for some reason. I've bought 7 different Crybaby revisions and I'm still not there. It's killing me, but it's part of the game. So yeah, I totally get you 😵‍💫

The way you described the 2203 as a "filthy pedal platform" is just perfect. It doesn't need them, but it works so well with those late '70s and early '80s pedals. Get the power-amp hot and the effects just become part of the sound in a really unique way.
Analog and vintage digital delays are so much fun especially with the 2203. Crank the master volume, put the delay in front of the amp and adjust the right amount of mix and feedback. With a dynamic amp the delay is also really dynamic and it kind of grows into your playing.
 
(I apologize for being slightly off-topic here.)

I'll have to track down one of those flangers. I'd assumed that it was too similar to the Micro Flanger (SAD512), but I'm addicted to flangers...

You bring up a good point with delays. Placing a delay in front of an amp like the 2203, where the tone is so dynamic and dependent on how strong the input is, when the repeats start fading out, they clean up a bit, too. That makes them much more dynamic, IMHO, and part of the tone, as you point out. Vintage digital, where the only digital part is the delay line, might even be better because the repeats are cleaner, but the dirt that analog adds also changes the character as the amp cleans up and the repeats get dirtier.

Budda, glad to hear that modern pedals work well with the 2203 as well (figured they would). Most of my pedals aren't modern, so I don't have a lot of experience there.

Anyway, back to the 2203!
 
(I apologize for being slightly off-topic here.)

I'll have to track down one of those flangers. I'd assumed that it was too similar to the Micro Flanger (SAD512), but I'm addicted to flangers...
Sent you a PM about this 🙂

You bring up a good point with delays. Placing a delay in front of an amp like the 2203, where the tone is so dynamic and dependent on how strong the input is, when the repeats start fading out, they clean up a bit, too. That makes them much more dynamic, IMHO, and part of the tone, as you point out. Vintage digital, where the only digital part is the delay line, might even be better because the repeats are cleaner, but the dirt that analog adds also changes the character as the amp cleans up and the repeats get dirtier.
Vintage digital delay (especially 8-bit like the Ibanez DDL) kind of makes the 2203 sound even more grittier and nasty with enough master volume. I guess analog as well. Have the master too low and the delay just sounds like a bright delay that’s in your way most of the time, but when you raise the master volume it blends in really nicely as it compresses.

Cleaning up your sound with guitar volume the delay also goes quieter. Turn on a boost and the delay gets a different kind of flavour from the boost as well, and it can be left on most of the time even without tap tempo. Hard to explain until you try it with the right setup. Definitely something almost no one uses anymore, but that’s how I run my delay 99% of the time. It’s just right for me.

You can try that inside Fractal with Vintage Digital Delay type. Bit Reduction to 8 (btw is the bitrate already lowered on that type???), feedback to 5-20 % and mix to 7-20 % depending whether you want the delay to stay more in the back or play rhythmic delay stuff instead. I use 340-390 ms delay time based on how I feel it suits the current song or my mood. If you feel like the delay is still too much on your way, you can lower the high cut to around 4-5 kHz.
 
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One of the things I picked up from the Eventide forum a while back was using Fibonacci sequence numbers for delay times. An over-simplification of the Fibonacci sequence is that it's an expression of the Golden Ratio. Using these times, for whatever reason, results in delays that work with any tempo. Lousy explanation, I know, but... each number is the sum of the previous two numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, and so on.

Numbers include: 144, 233, 377, and 610. The range you mentioned is right around 377. That's also close to the max delay times on old analog delays, and 610 is close to a Deluxe Memory Man and an Echoplex.

(completely off topic, but hopefully a little relevant to the conversation at the moment)
 
I’ve yet to try these amps in real life or in the Axe FX but I’m planning to this week.

So basically start with the 2203 (high) and add an SD-1 boost? I thought you wanted to crank the master volume on these to get some tube saturation. It’s a very basic amp so it can’t be that hard to make it sound good for high gain or metal tones?
 
By design, the 2203/2204 just isn't capable of tons of gain like many modern high-gain amps. If you want more, then you'll need the boost. I'd recommend the T808 or VS9 (TS), Super OD (SD-1) is good too, but just about any will do. Still, it's easy to get great sounds out of it without a boost. Check out the videos in this thread. There are several posts above that give suggestions for how to dial it in.
 
Crikey, more has appeared in this thread than I can quite take in, and all of it wonderfully Marshall 2203 oriented! Where to begin?
Small Stone (V2) with 2203 is IMHO the best phaser sound one can ever wish for. The re-issue just blows.
Never had a reissue, and in fact back in the day was using an early "Block logo" reissue MXR Phase 90 with my 2203. But I have a "not a reissue" Small Stone that I'm guessing is from about 1984. Lumped on me in the late 80's by the singer in the band, asking "Can you fix it?" The answer to that was yes, but then the answer to "Can I have it back?" disappointed him slightly. ;) And he can definitely have it back one day, but for the last 30 years he seems to have forgotten about it.
Also TS has been my go to drive pedal for 10 years with Marshalls.
They absolutely work together. I have a small collection of TS-10s in varying stages of modification. My main one for the last 20+ years is actually modified to replicate the TS-808, with a few SRV style mods to the tone circuit, but really isn't distinguishable from the Fractal VS-9 model in any meaningful way aside from pot tapers.
I have quite succesfully replicated all but the Performer flanger to my Fractal if you want to try that same pedalboard pictured above with your Fractal.
I'd been using a couple of EH Deluxe Electric Mistresses as my flangers for years now, one mid-90s reissue, and a (nearly) original made in New York 1978 version most recently. The workarounds back with the Axe FX II sort of worked (but were complex). I sold off the reissue a few years ago, but I've kept the '70s one for posterity. I'd be interested to hear where/why the Fractal Deluxe Mystery can't quite get in the ballpark of the DOD Performer. Give it a try and let me know please! I don't use a flanger much of the time, but it's very much a core part of my 2203 playing.
You bring up a good point with delays. Placing a delay in front of an amp like the 2203, where the tone is so dynamic and dependent on how strong the input is, when the repeats start fading out, they clean up a bit, too. That makes them much more dynamic, IMHO, and part of the tone, as you point out. Vintage digital, where the only digital part is the delay line, might even be better because the repeats are cleaner, but the dirt that analog adds also changes the character as the amp cleans up and the repeats get dirtier.
Oh my! The dirty goodness! The dynamics! When my Boss ME-5 had to go back for warranty work (1989? I was an early adopter!) I actually ended up going back to a Boss DM-2 (embarrassingly, borrowed from the same guy whose Small Stone I still have), and it sounded so good. This was pre-2203 for me, as I was using a Marshall BBRI (1962 2x12 combo) at the time. By the time I got into the lead up to my first 2203 I was totally sold on the even meatier goodness of tape delay, where the repeats get dirtier, darker, and even more wayward in pitch/tone if you let them. Definitely part of the tone, and for me, there's something really musical about hearing "unsophisticated" delay repeats cleaning up as they overdrive the amp less and less, but get less and less faithful to the notes/sounds played originally. Tape delay in front of a 2203 is a might thing!

The first 10 seconds of the track below were just guitar, into a Colorsound Supa Tonebender, then probably Deluxe Electric Mistress, then a WEM Copicat, with a thumbnail holding the tape away from the erase head so the repeats were endless. And of course into a cranked up 2203. It was never exactly the same every time live, but it was always good! I think a lot of the colour was tape saturation. If you listen to the B-side of the same single there's some delayed richness in the guitar break towards the end, I think for similar reasons.



Park 1210 arrived!
Another "Oh my!" I am totally intrigued, and haven't found time to hunt down a schematic to see what one of those might be capable of. We need to know this as well @MirrorProfiles.

Liam
 
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