JCM 800 vs. JCM 2000 DSL?

[spaceforlease]

hi.. im just curious.. is there any significant tonal difference between those two? which could nail the 80s metal (jason becker/vai/judas priest) tone better? i have the dsl 100, but i think it sounds harsh/not smooth/trebly. if i roll down the treble, it still sounds very bright.. it just muddens the clarity of my picking (ya know what i mean?)

from the serial no. im guessing its made after the new millenium: 2003-4
can it also be the speakers? im using a standard 1960a with stock speakers.

one more question about cabinets: does the model of the cabinet matter in terms of sound (eg. 1960A vs. silver jubilee cab)? or is it only the speakers that does the job?

 

[Keefoman]

The 1960 and silver jubilee are the same except some jubilees came with Celestion Vintage 30s(and the tolex of course.)
I also find it odd that your tone is still too bright with the treble turned all the way down. Sure your amp works as it should?

 

[spaceforlease]

yep... it works well from the last time i checked. its odd...

should i just sell the DSL and get a JCM 800 instead? i dont get why jcm 800s are more expensive than DSL, the DSL is said to be able to acquire a jcm 800 sound... even more! why??!!

so... cab models doesnt actually matter right?? so i can just get a $100 cab, as long as they're filled with vintage 30s they'll be as good as a silver jube cab?

 

[spaceforlease]

sorry for the unstoppable rant of questions btw... im still a noob in these kind of things ><

 

[RiverRatt]

It sounds like you have issues with the DSL. First off, I would bias the amp (tons of threads here if you don't know how). Every time my DSL50 has sounded harsh, the bias has been off quite a bit. For your DSL100, start with the bias at 90mA and work down from that until you find the sweet spot.

If that doesn't improve things drastically, it may be time to swap out some tubes. First, I would check and see if any of the preamp tubes are microphonic. Power up the amp and take it off standby. Take a pencil and tap the eraser end gently against each preamp tube (make sure the amp is turned up to at least 2-3 on the master vol). If you hear the tapping coming through the speakers loud and clear, replace that tube.

If you still aren't there, it may be time for some new tubes. Sometimes certain tubes will sound great in one amp and not so great in others. I tried a quad of JJ EL34L's in a 2203, and IMHO they sounded awful - very harsh and ice-picky. Winged C's and the Groove Tubes EL34M Mullard Reissues sound really good in my DSL, with the GT's being my favorite. I haven't bought many new preamp tubes lately. I tried some of the Tung-Sol reissues, which sounded good in my other amps but not so great in the DSL. Maybe someone else can chime in with some suggestions.

Your 1960A cabinet may not be the best sounding cab that Marshall ever made, but they do sound good. New speakers aren't going to make your amp sound that much better unless you get the head dialed in first.

 

[Keefoman]

yep... it works well from the last time i checked. its odd...

should i just sell the DSL and get a JCM 800 instead? i dont get why jcm 800s are more expensive than DSL, the DSL is said to be able to acquire a jcm 800 sound... even more! why??!!

so... cab models doesnt actually matter right?? so i can just get a $100 cab, as long as they're filled with vintage 30s they'll be as good as a silver jube cab?

Yes, a silver jebe cab WITH the v.30s that is. Most silver cabs were delivered with G12-75 speakers which are the same as in a 1960 cab.

 

[steelhorse]

Actually 90mv is on the high side. Bob from Euro suggests (and this from speaking with him on the phone) starting at 80mv and working slowly up from there. I wound up at 84mv and it's great. From the factory mine was a bit on the cold side.

I'm still working with the stock tubes mind you so I've not yet had the opportunity to try a premium matched set/kit but when I do I plan on going with the KT77 complete retube kit from Euro.

Keep in mind that since the 800 is out of production (to my knowledge) and in high demand therein lies the reason for the high pricing.

 

[big dooley]

its millivolts steelhorse... not milliamps!!!!!

 

[steelhorse]

My bad, yes, mV not mA. Thanks for catching that. You guys from the netherlands get sooo excited!

Better jump on RiverRatt for getting me thinking mA! (check his post)



Anyone who needs to bias this amp who never has should still consult the bias instructions.

 

[big dooley]

yeah, that's why i looked the "howto bias" video's on eurotubes for about 10 times in a row

well, dutchmen don't get excited fast (in fact we are a bit too rational)
but i don't wanna think about what will happen, if somebody who reads this, put new tubes in his DSL/TSL100 and set the bias on 90 mA!!! that would be horrible, unless it's done on the 4th of july, of course

 

[steelhorse]

I looked at your post with the !!!!!!!!!!

and envisioned you jumping up and down in your clogs flailing your arms screaming NOOOOOOOOOOO!!!!!!!!!!!!!

 

[big dooley]

why do you think the clogs caught fire?


and yes, those are my clogs
and yes, i do walk on them...
and yes, i do wear them on stage
and yes, the graphics are done by myself
and yes, i'm a proud, chauvinistic dutchman

 

[DragonSarc]

Im having the same experience with my TSL 100 Ive just retube it with new JJ E34Ls with ECC83s High gain with balance at v4 and its bright harsh and treblely at 80mV biased - tried 90 and sounds worse - Im thining switching to KT77s

 

[steelhorse]

why do you think the clogs caught fire?


and yes, those are my clogs
and yes, i do walk on them...
and yes, i do wear them on stage
and yes, the graphics are done by myself
and yes, i'm a proud, chauvinistic dutchman

Can you send me a pair of clogs with flames on it?

Seriously, they're cool

But I was thinking that you were jumping up and down frantically when I said mA instead of mV!

:Ohno:

 

[steelhorse]

Im having the same experience with my TSL 100 Ive just retube it with new JJ E34Ls with ECC83s High gain with balance at v4 and its bright harsh and treblely at 80mV biased - tried 90 and sounds worse - Im thining switching to KT77s

That's a bummer Dragon. You get the kit from Euro? Before throwing KT77's in there maybe you should give Bob a call and let him know what happened?

He may have some suggestions.

Good luck with that, keep us posted!

 

[big dooley]

Can you send me a pair of clogs with flames on it?

Seriously, they're cool

But I was thinking that you were jumping up and down frantically when I said mA instead of mV!

:Ohno:

that could be difficult... i don't know how to ship these properly... you live in the states i presume?
it takes about 4 to 5 days to prepare the blanc clogs... i do not paint them, i use drawing pencils and color them in with colorpencils... that takes some serious time to do...
after that's done, i spray about 2 or 3 layers of varnish on it with a rattlecan... i don't use clearcoat, because that's to hard and varnish adds a little warmth on the colors... this is the second pair i've done so far...
i really don't have enough time, to do such things on a regular basis

are you seriously thinking, to wear them?
the first month is like hell... your feet WILL hurt, no matter what...
after a while you've "learned" to walk properly with these thnings, and don't ever want to put normal shoe's back on
i don't recommend them, when you live in a hilly countryside... that's nearly impossible to walk on, especially when it rains... they'll get very slippery!
the netherlands have very flat surface's (apart from the so called dutch mountains, aka. dykes), so it's not a problem here

 

[big dooley]

back ontopic:

coming to think of it...
dragon, you put a balanced high gain tube on the PI, right?
after setting the bias from 80mV to 90mV your problem became worse.....

so, logically thinking, maybe a lower gain tube like a 5751 on the PI and/or V1 position will solve this?...
i don't have experience with this YET...
when my DSL100 is back from inspection, i'll try different preamp tubes on it...

experimenting with this, might solve your problem, and is a hell of a lot cheaper then pulling those new E34L's

 

[poeman33]

As to the original questions...
I played a JCM 800 in the eighties. It was wonderful...if you could crank it. I can get the same sound from my DSL at 2 that I could get from the JCM800 at 7.
I think cabinets do make a big difference. A 1960B sounds bigger than a 1960A for example even if they have the same standard speakers. There is more space inside the B cabinet to make sound. The same principle is applied to the tall vintage cabinets.

 

[RiverRatt]

My bad, yes, mV not mA. Thanks for catching that. You guys from the netherlands get sooo excited!

Better jump on RiverRatt for getting me thinking mA! (check his post)



Anyone who needs to bias this amp who never has should still consult the bias instructions.

Just to defend steelhorse and myself:

mA is legitimate. Bias probes place a 1-ohm resistor in series with the cathode, where you would measure the voltage drop across the resistor. If I'm not mistaken, the test points on the JCM2000 amps put the cathode current through the test probes, which is measured in mA. Get your reading, then use OHM's Law to convert to voltage (voltage = current x resistance). So, let's say the current we measured off the test points on our DSL100 is 85mA (.085A). We already know the resistor is 1-ohm. Plug all that into the formula and we have V=.085 * 1 which equals a voltage of, you guessed it, .085V or 85mV. How you measure depends on the method used. If you are reading the voltage drop across the resistor, you get mV. If you measure the current flowing through the test points (and your meter), you get mA.

Big Dooley, They will always be the same number. You will not see fireworks, the dead will not come back from the grave, and your amp will purr happily along in ignorant bliss of the whole argument. The only fireworks I've ever seen with my amp was when I accidentally touched one of the hot pins to the center ground one. It blew a ht fuse and scared the hell out of me. I'd only had the amp a couple of days when that happened.

Here's a link that explains this better than I can (by far). I do know what I'm talking about, I just can't make it sound right

http://www.amp-head.com/faq.php

 

[big dooley]

oh well... i've never been a hero with the theory on electronics...
that's why i looked the video's on eurotubes a couple of times to be sure...
and every info on the internet, about biassing a DSL/TSL head say's to measure mV at the testpoints and set the bias at 80/90mV (for 100watts)...
so when somebody's stating to set the bias at 80/90mA on the testpoints...
well then my own head will have a short circuit inside

no offence, but for noobs like me, this can get confusing