I couldn't help myself... what would you do?

[kewlpack]

:angel :angel :angel :angel :angel :angel

A friend of Reverbbb and mine, affectionately known as MLP recently bought a Cornford Hurricane. The amp sounds terrific. It has this purr/growl to it (on some settings) that is very cool. Reverbbb noticed it the other night at our jam. But that is for another thread...

Well - since MLP loves the Hurricane, he is striving to make his house "a Marshall-Free zone" as he puts it. To that end, he has agreed to let me purchase from him the following at a very nice price:

--Marshall JCM2000 Dual Super Lead Head - Mint (100w/new tubes)
--Marshall 1960AV 4x12 slant cabinet - Mint (stereo cab, Vintage 30 speakers, 280w handling)
--THD Yellow Jackets (these allow you to convert the Tubes to run at 20/40/100 watts - so I don't have to peel the paint to get a good saturated tone)
--Extra tubes (EL84s and 6L6s)
--Speaker cable
--…other tiny stuff…

I never dreamed I'd get the opportunity to score a "real" rig like this... so it wasn't even in my mind until MLP started seriously talking about it, and my wife smiled and said "that would be really cool for you". :shock

I just can't say how excited I am. Reverbbb can attest to the ear-to-ear grin I had last Friday when I was playing through it. Guess I wanted to share the joy and thank the Lord for allowing me to use something like this. Wow.

[Old Believer]

Man, that's cool. After what we were talking about on the RANT thread about buying gear, God gives you the go ahead to buy a marshall. yee haw.

[kewlpack]

Yeah. I didn't have my sights "really" set on anything like that till it practically fell in my lap through events that I had nothing to do with. :cool:

[Brad]

Congrats! Sounds like a very, very cool rig! I've been wanting one of those Cornfords ever since I read the first reveiw on them a few years ago. However, that Marshall rig is so sweet. Glad to hear it worked out well for both of you.

[stephen]

I never dreamed I'd get the opportunity to score a "real" rig like this... so it wasn't even in my mind until MLP started seriously talking about it, and my wife smiled and said "that would be really cool for you". :shock



Thats the coolest part of the story, well next to God treatin you right (cause you werent lookin for it [no gas], but I'm sure he knew you would love it!). \:D/

[Crunchyriff]

Kewlpack- I am finding out more and more that the DSL is a much-misunderstood, and very versatile amp that gets short shrift with many. (don't bother with a TSL as they are a servicing nightmare; and to my ears anyway, have a useless third channel).

There are a few tweaks and secrets that really make this DSL series shine. First, the bias needs to be set colder (yes colder!) than factory spec. I know this is not the norm, usually it's the other way around.
Decent tubes in the pre and power amp- (say, SED EL34's and EH12AX7's)and you are just about there.

I'll scrounge around for the info and if I can't find it, I'll email my buddy who has one and is floored with it- and get the skinny. (and he's owned many vintage Marshalls, and has a 68 Plexi right now).

The clean channel is just stellar, the dirt channel has a very broad range of tones; both channels have VERY useable tone controls; AND the FX loop can be used for a volume boost for solos. (not all amps can do this, as it's contingent on where in the amp's circuit it is placed- my Soldano couldn't do it FWIW).

If you are using any FX (say GT-8) you can use the 4CM, and bump your lead/solo presets up 3db, and voila!; or you can use an EQ box in the loop to bump it up.

I'll probably never sell my '75 JMP unless I am forced to; but my next Marshall will probably be the DSL...unless I go for the 18watt handwired jobbie.

Ya done well. Praise be to God!!

[Crunchyriff]

Kewl-

Update! My tone-bro suggests:

Bias @80mA per pair, & EH EL34's. (than factory bias, but sounds better in this particular circuit, and will be easier on your tubes, too!)

Amperex & Mullards in the Preamp. (duh! my favorites) If not these, I'd suggest Sylvanias for old production tubes (more reasonable $$); New Production glass I'd go with EH 12AX7's. I would NOT do the Tesla 12AX7/ECC83S. The EH's sound much better in Marshall pre's , IMHO.

Remember, the tone controls have a much broader range and are pretty sensitive; try these settings as a starting point.

Presence: 2-4
Treble: 4-5
Mids: 4-6 (with V30's you may want a bit on the lesser side)
Bass: 6-7
"Tone Shift" Button 'out'

"Deep" button 'out' (unless you are playing at bedroom levels, in this case then push it in and be prepared to be pleased.)

Adjust to taste. Have fun!

FWIW- If I don't like/score a Carvin Legacy after a hearty hands-on demo, I'm getting a DSL100 for my next amp.

[Ascension]

Congrats man :mrgreen: I really like the JCM 2000 DSL`s. I personally prefer them with the 6L6`s as I like the tight bottom end thump of the 6L6`s and also find they are more stable at the lower volumes I am forced to play with at Church.On the Pre-Amp tubes I just scored a few of the late 80`s military production NOS JAN Phillips 12AX7`s from my buddy Doug Preston over at http://www.dougstubes.com/ GREAT tones and not a bank busting price for a real USA made tube!! The DSL 100`s are one of my all time favorite amps and if the Carvin MTS wasn`t around probably would be what I would be playing as of now .

[kewlpack]

Wow guys! Thanks for all the great input. :)

MLP just retubed the amp about two months ago and it has seen only slight use. I think he also adjusted the bias (Reverbbb helped with that). I'll have to ask Rev where he set it at.

I can't wait to get it over to the house (next Friday or so). :)

[seagullplayer]

Dude, I wouldn't even know how to plug all that stuff in! Sounds like God got it to the right guy! Congrates, Make a joyfull noise unto the Lord, LOUD! :cool:

And give your wife a big kiss. Might be a good day to bring home flowers...

[reverbbb]

Wow guys! Thanks for all the great input. :)

MLP just retubed the amp about two months ago and it has seen only slight use. I think he also adjusted the bias (Reverbbb helped with that). I'll have to ask Rev where he set it at.

I can't wait to get it over to the house (next Friday or so). :)

MLP put some GT 12AX7M (Mullard R.I.) in that amp for the preamps. I was so convinced, that I put them in my 50W head also. We biased the EL34s to about 42ma. It was difficult because of the way the two circuits seemed to be tied together. There was something very different about setting the bias on the DSL. I don't remember the brand of the EL34s.

Crunchy:

80ma seems awefully high. That would tend to wear down the tubes much faster, but it would give a fatter tone. Most of the time, the tone starts getting weird for me past 45ma. We did the plate voltage formula of 70%. MLP seemed to like it there.

[prscustom24]

80ma per pair; 40ma per bottle, a reasonable value imo.

[kewlpack]

Hey Rev -

Once we got the specs from Crunchy figured out - wanna tweak the DSL (after I get it over to the house)?? Sounds like we are already pretty close though - but I have no clue what I'm talking about (other than the 42 is close to 40 per pair)... LOL

You know, I could run that DSL into my 1x12 Fender too because it has an 8ohm Celestion G12T-100 in it... for when I can't move the 4x12 around... sweet! A Marshall head on a Fender amp/cab - hehehehe... it's a Farshall or a Marnder hybrid... :popcorn

[prscustom24]

20 ma per bottle is too cold for me, but that is typical factory bias point for a lot of amp makers. 35ma per tube is a decent compromise between sound quality and tube lifetime.

Love hybrids. Mine is Digitech preamp, Marshall power amp (but 6L6/5881, not EL34), Fender Tonemaster cabs w/ Weber Blue Dogs. Perfect.

[Crunchyriff]

Again, yes that's 80mv per pair; and while YES, that normally is way too cold in your average tube amp, in the DSL, according to him, it's da bomb. This is with EH EL34's, mind you.

He wasn't too impressed with the stock bias setting's sound and started playing around with it- said that these are biased pretty hot from the factory in comparison to many other tube amps (the usual 'cold' settings), but he wasn't too keen on what he was hearing. So, he put the chassis on the bench, plugged in a cab and guitar and started bringing down the bias, due to it being high enough to begin with that there was not too much room to go up. He started bring it down...with very pleasant results.

I'm not here to argue with you guys about general tube servicing issues as I agree with your general, common-practice premise; just passing the info. This one is just a different animal. It sure doesn't hurt to try, does it?
:-)

My long-time friend is not a newby or hack, and knows Marshalls inside and out very, very well. Just recently did a ground-up rebuild/restoration of another 68 plexi that he saved from total cannibalization by various "parts vultures". It roars.

[reverbbb]

I guess we are talking about the same thing. My bias probe will work on two tubes at the same time. I can only "measure" one tube at a time though. I set the amp to 45mv(ma) for each tube - one pair at a time. It sounds like we are talking 90mv for the pair and 45mv for each tube. So, we are running a little hotter than your 80mv suggestion.

Am I understanding this correctly? I am VERY new at this bias stuff.

[Crunchyriff]

reverbb- bro, I've never biased an amp in my life. yet...

So you are ahead of me!

But I have wanted a bias-king!

I just don't want to get jolted. I have an EXTREME respect for current. :mrgreen:

[SAguitar]

Sounds like a real sweet ride! Praise the Lord with a loud and joyful amp!

[Crunchyriff]

..and a twist of the volume knob!! :mrgreen: :shock

[prscustom24]

I guess we are talking about the same thing. My bias probe will work on two tubes at the same time. I can only "measure" one tube at a time though. I set the amp to 45mv(ma) for each tube - one pair at a time. It sounds like we are talking 90mv for the pair and 45mv for each tube. So, we are running a little hotter than your 80mv suggestion.

Am I understanding this correctly? I am VERY new at this bias stuff.

Sounds right. Your bias probe inserts 1 ohm between the tube's cathode and ground. Measure the voltage drop across it, that's the cathode current, which is, for all practical purposes, the same as the anode (plate) current.

I've always installed the 1-ohm resistor and left it in there, in my amps.

Either way, setting the bias by that method beats the transformer shunt method every day, for safety.

[prscustom24]

I guess we are talking about the same thing. My bias probe will work on two tubes at the same time. I can only "measure" one tube at a time though. I set the amp to 45mv(ma) for each tube - one pair at a time. It sounds like we are talking 90mv for the pair and 45mv for each tube. So, we are running a little hotter than your 80mv suggestion.

Am I understanding this correctly? I am VERY new at this bias stuff.

Sounds right. Your bias probe inserts 1 ohm between the tube's cathode and ground. Measure the voltage drop across it, that's the cathode current, which is, for all practical purposes, the same as the anode (plate) current.

I've always installed the 1-ohm resistor and left it in there, in my amps.

Either way, setting the bias by that method beats the transformer shunt method every day, for safety.

Edit: Don't get carried away with the experimentation into higher bias values, lest you exceed the plate dissipation. You will know you have done this when the plates glow cherry red. This is a very bad thing.

[Crunchyriff]

Don't get carried away with the experimentation into higher bias values, lest you exceed the plate dissipation. You will know you have done this when the plates glow cherry red. This is a very bad thing.

That is, unless you want to keep tube MFG's moving more product!

This is a very bad thing.

You'll never be invited on Martha Stewart's show with that kinda attitude! :ROFL

[prscustom24]

Don't get carried away with the experimentation into higher bias values, lest you exceed the plate dissipation. You will know you have done this when the plates glow cherry red. This is a very bad thing.

That is, unless you want to keep tube MFG's moving more product!

This is a very bad thing.

You'll never be invited on Martha Stewart's show with that kinda attitude! :ROFL

Somehow I think Martha would understand how it'd be criminal to destroy a quartet of NOS Mullards or Black Plates that way. But I'll amend my warning to include "if you're gonna experiment, do it with Sovteks or any of the Chinese trash bottles. Some would even argue you'd be doing the world a service, taking 'em out."

HTH

[Crunchyriff]

Oh I'm not disputing the tech info here at all on this issue, just chiding you about "a very bad thing" is 180 degrees away from Martha-speak!

[prscustom24]

Ah, so.

I've never actually heard Martha speak. Truth is, even with an electron microscope, you could not locate my interest in anything Martha. :-)

[Crunchyriff]

Nor I.... :mrgreen:

[Captain Crunch]

I submitted a very long reply in regards to biasing but it seems the forum not only lost my post, but also my login info. LOL

BTAIM, when biasing the DSL100 amps you are testing two tubes at a time. That is why the readings are double that of a DSL50. DO NOT try to set the bias of a DSL50 at 80mv per tube!!! 80mv bias on a DSL100 is equal to 40mv bias on a DSL50.

If you want me to resubmit instructions and information on biasing your DSL, let me know and I would be happy to help you out.

[kewlpack]

OOoo man that is a drag. :( I hate it when I lose a good, long post!

I think we got it all figured out as far as biasing. I'm gonna leave it where Reverbbb set it for now.

BTW, FRIDAY is the day this big black behemoth COMES HOME!!! WooooHOOOOO!

Stand back - the elephant is going to sneeze! :popcorn

[Captain Crunch]

I guess we are talking about the same thing. My bias probe will work on two tubes at the same time. I can only "measure" one tube at a time though. I set the amp to 45mv(ma) for each tube - one pair at a time. It sounds like we are talking 90mv for the pair and 45mv for each tube. So, we are running a little hotter than your 80mv suggestion.

Am I understanding this correctly? I am VERY new at this bias stuff.

Yes, the 90mv/pair 45mv/tube on a DSL is the "stock" setting on the amp. This is a bit hot for an EL34 since the B+ on a DSL normally runs around 450V. The "70% of max dissipation" standard would dictate a bias setting of 38.88mv per tube at idle, given 450V on the plates. The 45mv stock setting puts the tube at a bit over 80% at idle (even more if the B+ is higher than 450V). This is why most users find it to be a bit harsh when they first play through a DSL.

Right now (as Crunchyriff said) I am really happy running at 80mv per pair. Of course, it is purely a matter of taste. However, the factory suggested setting may burn through your output tubes more quickly.

[Captain Crunch]

I think we got it all figured out as far as biasing. I'm gonna leave it where Reverbbb set it for now.


If it sounds good to you, then all is great! :cool:

[kewlpack]

Little update...

I just gave the DSL100/Cab back to my friend this weekend, largely due to this fact. The 100w head and 4x12 cab were just too big for what I really need or would ever put to good use. It sounded alright, but had to get too loud for my practical use very quickly.

Plus luggin' that thing would've been rough (my jam area is upstairs)!

For now, I realize that I'm pretty happy with my solidstate and modeling technology. It will only get better with each generation (just like digital music and television)... and is more portable/flexible for what I do.

I'm glad I had the opportunity to play that monster for awhile just the same.

[stephen]

Little update...

Plus luggin' that thing would've been rough (my jam area is upstairs)!


Think of all the chiropractic bills your gonna save!