JCM800 vs SLO

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Both amps and both channels of the SLO sound great. There is a certain very slight hollow character with the SLO Crunch that comes out more/less depending on what you're playing and where you are on the fretboard. I'd probably pick the one with the best/most useable loop.
I don’t use fx loops but people say the new bad loop is good. Maybe I’ll test it
 
These bloom with the Master on "6".
Wear hearing protection.
500+ bonus points for [not] playing anything VH >
I'd recorded clips of a 2204 with the master at 2 and at 6, and I think most people (myself included) preferred the tone at 2. It just starts getting mushy beyond that IMHO. Master on 2 is still damn loud haha.

I'd had an '89 SLO but sold it because I just always preferred the 2204 for lead or rhythm.
 
I don’t use fx loops but people say the new bad loop is good. Maybe I’ll test it
The new loop is tube buffered and not a Metroloop.
Friedman basically redesigned the SLO [with Mike] to improve what Mike could not or would not change in 40+ years.
 
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I'd recorded clips of a 2204 with the master at 2 and at 6, and I think most people (myself included) preferred the tone at 2. It just starts getting mushy beyond that IMHO. Master on 2 is still damn loud haha.

I'd had an '89 SLO but sold it because I just always preferred the 2204 for lead or rhythm.
But are you in your bedroom or a music hall that seats 300 people ?
4 to 6 in your house isn't the context i meant.
However i play on 4 in my living room and it sounds glorious but no matter how recorded never sounds like if your in the room with me.
A 50 watt Marshall on 2 is lost w/a bass & drummer.
As for "mushy" that could be alot of things especially speakers.
 
I'd recorded clips of a 2204 with the master at 2 and at 6, and I think most people (myself included) preferred the tone at 2. It just starts getting mushy beyond that IMHO. Master on 2 is still damn loud haha.

I'd had an '89 SLO but sold it because I just always preferred the 2204 for lead or rhythm.
2 is nearly drowning out the drummer honestly. That’s about as high as it ever gets for me
 
But are you in your bedroom or a music hall that seats 300 people ?
4 to 6 in your house isn't the context i meant.
However i play on 4 in my living room and it sounds glorious but no matter how recorded never sounds like if your in the room with me.
A 50 watt Marshall on 2 is lost w/a bass & drummer.
As for "mushy" that could be alot of things especially speakers.
Well that’s fair in terms of size of where you’re playing. But are we pretending we’re not micd up?
 
2 is nearly drowning out the drummer honestly. That’s about as high as it ever gets for me
I ruptered an eardrump in the 80's playing my 2204 JMP dimed all the time. But i used to point the cab at my head.
Bad idea.
I keep SPL's below the waist these days with good reason.
 
Bear with me, because now we're getting more technical and I'm not a electronics expert. What you’re most likely hearing in this situation is the power tubes running at different, sub-optimal voltages that lead to significant changes in tone. The 2555x runs a quad of EL34s stock and has a power transformer that is designed to supply those EL34s the voltages required to deliver the feel and sound Marshall wants for those tubes. AFAIK, there are no switches or dials to reduce or increase the voltages supplied to the power tubes in the amp. So in this case, if you put 6550s in, they will operate, but at a sub-optimal level, because they are being fed the same level of voltage that would typically be ideal for 4x EL34s, but not for 4x 6550s to deliver the same sound and output the amp designer had in mind. If the tubes are similar in operating spec then there will be less significant differences in tone.

If anyone has more knowledge in this area, please correct me if I'm wrong.


I feel like this is a good example. I can't hear a difference between the 6L6 or EL34 tubes in this clip.
I agree to a point....Older JMP/JCM 800s that came with 6550s, are running as you say...as those transformers are designed for 34s. I always biased the 6550s as if they were 34s, to not stress the transformers.
But, the 2555x has a chart that allows for the recommended bias numbers of each tube type. So, that transformer set isn't designed for only 34 usage, if that chart is mfr recommended.
Now, would the amp sound better if the transformers were tube type specific and you only ran what it was designed for? Possibly. Be interesting to put a set of 2203x transformers in the 2555x and hear the differences, when using only 34s in each.
 
I agree to a point....Older JMP/JCM 800s that came with 6550s, are running as you say...as those transformers are designed for 34s. I always biased the 6550s as if they were 34s, to not stress the transformers.
But, the 2555x has a chart that allows for the recommended bias numbers of each tube type. So, that transformer set isn't designed for only 34 usage, if that chart is mfr recommended.
Now, would the amp sound better if the transformers were tube type specific and you only ran what it was designed for? Possibly. Be interesting to put a set of 2203x transformers in the 2555x and hear the differences, when using only 34s in each.
With other amps like the Naylor’s they were designed around 6L6’s by default, but I still much preferred EL34’s in them (some guys really liked KT88’s in it), this small Ronin amp I have came stock with 6L6’s (designed mainly for those and 6V6’s), but much preferred 6550’s, KT88’s and 6V6’s, the latest one I got has massive transformers (amp weighs almost 80 lbs) designed around KT88’s, but I much preferred EL34’s and 6L6’s. In all cases I heard the same relative differences I’m used to hearing in the different tube types

I’m sure the transformers are still a big part of what tubes sound good in an amp, but it seems to me IME more about just what tube complements the amp’s character like EL34’s just sounding good in Marshall’s, 6L6’s in most American voiced amps. Kind of like some people might look good wearing blue, others look good in red, etc. I think those amp guys saying you can get same results with eq setting are either not listening in a discerning enough way to tube swaps or don’t want guys go too crazy exploring the tube rabbit hole
 
With other amps like the Naylor’s they were designed around 6L6’s by default, but I still much preferred EL34’s in them (some guys really liked KT88’s in it), this small Ronin amp I have came stock with 6L6’s (designed mainly for those and 6V6’s), but much preferred 6550’s, KT88’s and 6V6’s, the latest one I got has massive transformers (amp weighs almost 80 lbs) designed around KT88’s, but I much preferred EL34’s and 6L6’s. In all cases I heard the same relative differences I’m used to hearing in the different tube types

I’m sure the transformers are still a big part of what tubes sound good in an amp, but it seems to me IME more about just what tube complements the amp’s character like EL34’s just sounding good in Marshall’s, 6L6’s in most American voiced amps. Kind of like some people might look good wearing blue, others look good in red, etc. I think those amp guys saying you can get same results with eq setting are either not listening in a discerning enough way to tube swaps or don’t want guys go too crazy exploring the tube rabbit hole
I’m really not buying the “power tubes don’t affect sound” argument. At all. They also change the way an amp feels and responds. Not sure why this is a popular thing to say these days, I guess cause fryette and Friedman have said it.
 
I agree to a point....Older JMP/JCM 800s that came with 6550s, are running as you say...as those transformers are designed for 34s. I always biased the 6550s as if they were 34s, to not stress the transformers.
But, the 2555x has a chart that allows for the recommended bias numbers of each tube type. So, that transformer set isn't designed for only 34 usage, if that chart is mfr recommended.
Now, would the amp sound better if the transformers were tube type specific and you only ran what it was designed for? Possibly. Be interesting to put a set of 2203x transformers in the 2555x and hear the differences, when using only 34s in each.


2203x trannies are made in Vietnam now. No more Dagnall UK.
I wouldn't expect miracles.
 
the marshall just has that chime i still prefer but the slo does sound good here too
 
If wood and tubes don't matter, is tone still in the fingers? Or did that go out the window with vaccinations?
 
2203 and SLO are two completely different amps/tones—need both
I 100% agree.

While it's not an 800, my 50w Jubilee has a similar sound and I also have a custom 50w Brit-Tone SLO and the amps could not be more different.

The SLO has GOBS more gain and much punchier and clearer when pushed hard on stage (which IMO is really where the SLO comes to life).

The Jubilee has a much better low gain crunch. The SLO's crunch channel is still great but not as warm and smooth as the Jubilee.

The SLO gets super fat and compressed but still clear sounding when the gain is pushed past noon.
 
I think @pipboy90's point that may be missed is that of course a circuit designed around a particular tube sounds different when you put another type in, just as it would sound different if you replaced another part of the circuit with one of a different value. However this doesn't mean that you couldn't design two amps that each use a different type of tube to sound the same, because simply biasing tubes within acceptable range is only the most basic part of designing around a particular tube. Just as you might notice the same effect across multiple amps if you change the cold clipper cathode resistor from 10k to 39k (Marshall to Soldano values), you could also notice the same effect (a different one, of course) across multiple amps when going from EL34 to 6L6, EL34 to KT77, etc. but that's only an effect of the relative change of a circuit and not an effect that defines how any amp would sound with that type of tube.
 
Thicker is a great descriptor. Nice vids and nice amp but bad sales pitch for an SLO as ai hear/appreciate the difference between the two but don’t see another $4K justified to get that over the 2203 in hand… esp w Hot Mods units available.
 
Thicker is a great descriptor. Nice vids and nice amp but bad sales pitch for an SLO as ai hear/appreciate the difference between the two but don’t see another $4K justified to get that over the 2203 in hand… esp w Hot Mods units available.
Are you saying this thing will turn a 2203 into an SLO? I dunno man
IMG_7226.jpeg
 
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