Just Got New Tubes For My DSL 100

axl2 · 10-06-2008, 12:32 AM

Just replaced my Groove Tube stock pickups with 4 JJ ECC83's And 4 Svetlana EL34 EL34's. Which are the same "Tube Types" that were in the stock.

So question is can I simply just go ahead and screw them in and play or I have to do some kind of biasing??

PaoloJM · 10-06-2008, 03:33 AM

Quote:

Originally Posted by axl2

Just replaced my Groove Tube stock pickups with 4 JJ ECC83's And 4 Winged EL34's. Which are the same "Tube Types" that were in the stock.

So question is can I simply just go ahead and screw them in and play or I have to do some kind of biasing??

You need to bias the El34's which are the power tubes. The Eurotubes (euro-q)web-site gives an excellent video guide for doing this.

steelhorse · 10-06-2008, 06:41 AM

+1 what Paolo said

spaceforlease · 10-06-2008, 12:15 PM

how does he actually change the volts? i bought the multimeter, but the guy said that thing is only for MEASURING the volts... not changing it to 90 to 84.

poeman33 · 10-06-2008, 12:20 PM

Quote:

Originally Posted by spaceforlease

how does he actually change the volts? i bought the multimeter, but the guy said that thing is only for MEASURING the volts... not changing it to 90 to 84.

Thanks to the great info from other posts about the video available on Eurotubes...here is the link to the video on how to bias for the DSL100
euro-m

axl2 · 10-06-2008, 12:42 PM

kk so I need to go out and get myself a Multi-Meter to do this. Other then that, it looks simple.

spaceforlease · 10-06-2008, 01:15 PM

he didnt quite show how to change WITH the multimeter. it just went up and down magically from what im seeing.

axl2 · 10-06-2008, 01:22 PM

Quote:

Originally Posted by spaceforlease

he didnt quite show how to change WITH the multimeter. it just went up and down magically from what im seeing.

That's true, He didn't have the camera on the right side where he was doing the "turning". I dunno lol

steelhorse · 10-06-2008, 07:00 PM

I think Bob realized that with the bias probes and the multimeter setup he used he probably confused a few folks but it's really simple with the DSL100.

All you need is a decent multimeter. I ordered mine form Euro Tubes.

Take the multimeter and set the dial to the 9:00 position which will be in the DCV 200m setting.

Take the black lead and plug that into the COM port at the bottom right side of the meter.

Take the red lead and plug it into the DC port

I have alligator clip adapters so I use one on the black lead which I clip on to the ground post on the amp bias adjustment.

You'll be using the red lead for the readings.

Be sure the amp has been on for a few minutes to get plenty hot on standby.

Take the amp OFF standby like you are going to play.

Take the red lead and touch each test point on the bias adjustment of the DSL to see where you're at.

We're looking for a reading of between 80 and 90 mV.

With an insulated or plastic small head Phillips screwdriver make MINUTE adjustments to 1 side at a time (you'll see what I mean when you adjust yours!). Remember when you make one side hotter it will cool the opposite side down some, so it will be a back and forth venture until the see-saw quits and you get near identical readings on both sides.

I set mine to 86mV. Played with it for a few days, and went back and checked it for drift but it was still very close so I left it.

The things that could make it easier is of course getting another multimeter, clipping both grounds to the ground post and the positive lead of each to one test point so all you need to do is watch the meters while making the adjustment but it's really simple to accomplish the same thing with only 1 meter, it just takes a little time and patience.

I recently read on the Euro site that the factory test points on the JSX heads are unreliable and they had steps to follow to bias it properly. With that head I switched the meter to the 4:00 position (DCA) moved my red lead to the mA port and used a bias probe on 1 of the tubes (it needs to be a matched set to do it this way). It took some time but with the JSX you just adjust the little dial to get the bias set.

Hope this helps!

axl2 · 10-06-2008, 07:12 PM

Quote:

Originally Posted by steelhorse

I think Bob realized that with the bias probes and the multimeter setup he used he probably confused a few folks but it's really simple with the DSL100.

All you need is a decent multimeter. I ordered mine form Euro Tubes.

Take the multimeter and set the dial to the 9:00 position which will be in the DCV 200m setting.

Take the black lead and plug that into the COM port at the bottom right side of the meter.

Take the red lead and plug it into the DC port

I have alligator clip adapters so I use one on the black lead which I clip on to the ground post on the amp bias adjustment.

You'll be using the red lead for the readings.

Be sure the amp has been on for a few minutes to get plenty hot on standby.

Take the amp OFF standby like you are going to play.

Take the red lead and touch each test point on the bias adjustment of the DSL to see where you're at.

We're looking for a reading of between 80 and 90 mV.

With an insulated or plastic small head Phillips screwdriver make MINUTE adjustments to 1 side at a time (you'll see what I mean when you adjust yours!). Remember when you make one side hotter it will cool the opposite side down some, so it will be a back and forth venture until the see-saw quits and you get near identical readings on both sides.

I set mine to 86mV. Played with it for a few days, and went back and checked it for drift but it was still very close so I left it.

The things that could make it easier is of course getting another multimeter, clipping both grounds to the ground post and the positive lead of each to one test point so all you need to do is watch the meters while making the adjustment but it's really simple to accomplish the same thing with only 1 meter, it just takes a little time and patience.

I recently read on the Euro site that the factory test points on the JSX heads are unreliable and they had steps to follow to bias it properly. With that head I switched the meter to the 4:00 position (DCA) moved my red lead to the mA port and used a bias probe on 1 of the tubes (it needs to be a matched set to do it this way). It took some time but with the JSX you just adjust the little dial to get the bias set.

Hope this helps!

Thanks a TON! Yeah when he used the seperate instrument it confused me a bit. But I was on the right thought plane since I read yours. I didn't know what setting to set the knob on the meter at but you've covered that for me. Now I just need to buy myself a Multimeter and I'm set. I think I'll split the difference and go for 85-86 like you did.

steelhorse · 10-06-2008, 07:27 PM

Cool!

Yeah, either order one form Euro Tubes or get a decent one at Radio Shack. The really cheap ones there are crap fyi.

Let us know how it goes.

I just got a new complete re-tube kit for my new DSL100 but since I got the TSL100 I'm looking to sell it or trade it for a Vintage Modern so I haven't installed it.

DevilsEve666 · 10-06-2008, 08:22 PM

Listen to STEELHORSE he knows what's up

DevilsEve666 · 10-06-2008, 08:30 PM

pRS1C-2266866w345.jpg

DON'T buy this one if you get one at radio shack, i couldn't even get a dc voltage reading on a friggin' 9-volt, thought i was an idiot, but then I read the reviews and found that I wasn't alone...

axl2 · 10-06-2008, 08:49 PM

I'm heading into Radio Shack tomorrow. I'll look for something in the 20 dollar range I guess? Not sure how much these things cost to be honest... I seen a few for 15 dollars off ebay.

DevilsEve666 · 10-06-2008, 09:10 PM

with these things I guess price isn't always the best factor to consider...like that radio shack one that I bought was $29.99 and then i got the one from the eurotubes sight and it was 10.00 and it is excellent!! I had my amp biased in no time...

steelhorse · 10-06-2008, 09:12 PM

+1, get the one from Euro Tubes!

axl2 · 10-06-2008, 09:51 PM

Wow, K guys thanks for the help. I just ordered the Multimeter on the Euro Tubes site.

stock_hippie · 10-06-2008, 10:50 PM

not getting the downloAd...is it me?

solarburnDSL50 · 10-07-2008, 12:37 PM

Part of biasing your DSL is getting plate voltage too. You figure this number and you can get your correct bias number. DSL's run plate voltage from 450 to 500 with EL34's usually somewhere in between. Marshall recomends 40 to 45 bias. I set mine cooler at 36 with Tung Sol EL34B's.

Example formula - 25 watts disipation divided by lets say 450 plate volts = .055
Then multiply .055 times 60 or 70% depending how hot you want to run the tubes. .055 x .6 = .033 .055 x .7 = .038.

So at 60% your bias number is 33. At 70% your bias number is 38. Eurotubes didn't show how to check for voltage in the DSL vid. He just set the bias which is what you do after getting the plate voltage and crunching the numbers per the formula. He does show how with the JCM 800 vid though.

steelhorse · 10-07-2008, 05:29 PM

I spoke with Euro Tubes about this and this was their response:

"The plate voltage is a fixed amount of voltage supplied buy your transformer to the plates of the power tubes. It’s not variable and you really don’t need to worry about it.

Thanks,

Eddie"

fwiw

solarburnDSL50 · 10-07-2008, 10:35 PM

Quote:

Originally Posted by steelhorse

I spoke with Euro Tubes about this and this was their response:

"The plate voltage is a fixed amount of voltage supplied buy your transformer to the plates of the power tubes. It’s not variable and you really don’t need to worry about it.

Thanks,

Eddie"

fwiw

Watch his JCM 800 vid and tell me the plate voltage is a fixed number. I will say that there is not much difference to the bias number even when there is a 20 volt diff in plate voltage from tubes to tubes. I fail to see where plate voltage is fixed in one place. Call Voodoo Amps and tell them the plate voltage is a fixed number. You will get a different answer.

Makes no difference to me if someone biases diffferently. Hey and I'm just learning all about htis too.

steelhorse · 10-07-2008, 11:31 PM

I hear ya solar but being that the dude that put out the 800 vid clip owns the company I got the response from, it stands to reason that perhaps the 800/900 series and older are different animals than the DSL/TSL's.

They seem to be on the ball over there at Euro so no real reason for me to doubt their information.

And I have watched the 800 clip and wondered the same thing but they told me the plate voltage didn't apply with the TSL so I didn't worry about it.

Oh well, we're all learning!

axl2 · 10-08-2008, 12:03 AM

It appears my first official thread on here has been put to good use lol

solarburnDSL50 · 10-08-2008, 12:46 AM

Quote:

Originally Posted by steelhorse

I hear ya solar but being that the dude that put out the 800 vid clip owns the company I got the response from, it stands to reason that perhaps the 800/900 series and older are different animals than the DSL/TSL's.

They seem to be on the ball over there at Euro so no real reason for me to doubt their information.

And I have watched the 800 clip and wondered the same thing but they told me the plate voltage didn't apply with the TSL so I didn't worry about it.

Oh well, we're all learning!

I hear ya bro. I actually learned how to bias my DSL from his site. I thought I was all good until Trace from Voodoo told me alot more about getting these amps (DSL) biased not to mention on tubes. It was info overload.

At any rate here is a bias table for EL34's from Jim Jones on Webers website:
EL34 - 25W Hot (70%) Avg (60%) Cool (50%)

300V 58mA 50mA 42mA
325V 54mA 46mA 38mA
350V 50mA 43mA 36mA
375V 47mA 40mA 33mA
400V 44mA 38mA 31mA
425V 41mA 35mA 29mA
450V 39mA 33mA 28mA
475V 37mA 32mA 26mA
500V 35mA 30mA 25mA

With this you can see how little the bias numbers change from plate voltage to plate voltage biased hot or cold. So if you know DSL's run from 450 to 500 plate voltage then you can get in the neighborhood for the bias and just fine tune it to what sounds best. I have a MM OT and my bias is stable. Watch out for run away bias with DSL's stock OT per Voodoo. The bias may wander too hot while adjusting it and the tube can red plate. Make small pot adjustments either way.

steelhorse · 10-08-2008, 01:28 AM

Yeah, see my post above in describing the bias adjustments.

Minute adjustments!

solarburnDSL50 · 10-08-2008, 10:27 AM

Quote:

Originally Posted by steelhorse

Yeah, see my post above in describing the bias adjustments.

Minute adjustments!

I forgot to tell you that your "how to" post was great. It took time to write all that out and I know guys here will appreciate that.

steelhorse · 10-08-2008, 01:23 PM

Thanks!

10-06-2008, 12:32 AM	#1 (permalink)
axl2 Member Join Date: Oct 2008 Location: Mahone Bay, NS, Canada Posts: 35	Just Got New Tubes For My DSL 100 Just replaced my Groove Tube stock pickups with 4 JJ ECC83's And 4 Svetlana EL34 EL34's. Which are the same "Tube Types" that were in the stock. So question is can I simply just go ahead and screw them in and play or I have to do some kind of biasing?? Last edited by axl2; 10-06-2008 at 10:12 PM.

10-06-2008, 06:41 AM	#3 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 +1 what Paolo said

10-06-2008, 12:15 PM	#4 (permalink)
spaceforlease Member Join Date: May 2008 Posts: 53	Re: Just Got New Tubes For My DSL 100 how does he actually change the volts? i bought the multimeter, but the guy said that thing is only for MEASURING the volts... not changing it to 90 to 84.

10-06-2008, 12:42 PM	#6 (permalink)
axl2 Member Join Date: Oct 2008 Location: Mahone Bay, NS, Canada Posts: 35	Re: Just Got New Tubes For My DSL 100 kk so I need to go out and get myself a Multi-Meter to do this. Other then that, it looks simple.

10-06-2008, 01:15 PM	#7 (permalink)
spaceforlease Member Join Date: May 2008 Posts: 53	Re: Just Got New Tubes For My DSL 100 he didnt quite show how to change WITH the multimeter. it just went up and down magically from what im seeing.

10-06-2008, 07:00 PM	#9 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 I think Bob realized that with the bias probes and the multimeter setup he used he probably confused a few folks but it's really simple with the DSL100. All you need is a decent multimeter. I ordered mine form Euro Tubes. Take the multimeter and set the dial to the 9:00 position which will be in the DCV 200m setting. Take the black lead and plug that into the COM port at the bottom right side of the meter. Take the red lead and plug it into the DC port I have alligator clip adapters so I use one on the black lead which I clip on to the ground post on the amp bias adjustment. You'll be using the red lead for the readings. Be sure the amp has been on for a few minutes to get plenty hot on standby. Take the amp OFF standby like you are going to play. Take the red lead and touch each test point on the bias adjustment of the DSL to see where you're at. We're looking for a reading of between 80 and 90 mV. With an insulated or plastic small head Phillips screwdriver make MINUTE adjustments to 1 side at a time (you'll see what I mean when you adjust yours!). Remember when you make one side hotter it will cool the opposite side down some, so it will be a back and forth venture until the see-saw quits and you get near identical readings on both sides. I set mine to 86mV. Played with it for a few days, and went back and checked it for drift but it was still very close so I left it. The things that could make it easier is of course getting another multimeter, clipping both grounds to the ground post and the positive lead of each to one test point so all you need to do is watch the meters while making the adjustment but it's really simple to accomplish the same thing with only 1 meter, it just takes a little time and patience. I recently read on the Euro site that the factory test points on the JSX heads are unreliable and they had steps to follow to bias it properly. With that head I switched the meter to the 4:00 position (DCA) moved my red lead to the mA port and used a bias probe on 1 of the tubes (it needs to be a matched set to do it this way). It took some time but with the JSX you just adjust the little dial to get the bias set. Hope this helps!

10-06-2008, 07:27 PM	#11 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 Cool! Yeah, either order one form Euro Tubes or get a decent one at Radio Shack. The really cheap ones there are crap fyi. Let us know how it goes. I just got a new complete re-tube kit for my new DSL100 but since I got the TSL100 I'm looking to sell it or trade it for a Vintage Modern so I haven't installed it.

10-06-2008, 08:22 PM	#12 (permalink)
DevilsEve666 Member Join Date: Apr 2008 Posts: 30	Re: Just Got New Tubes For My DSL 100 Listen to STEELHORSE he knows what's up

10-06-2008, 08:30 PM	#13 (permalink)
DevilsEve666 Member Join Date: Apr 2008 Posts: 30	Re: Just Got New Tubes For My DSL 100 pRS1C-2266866w345.jpg DON'T buy this one if you get one at radio shack, i couldn't even get a dc voltage reading on a friggin' 9-volt, thought i was an idiot, but then I read the reviews and found that I wasn't alone...

10-06-2008, 08:49 PM	#14 (permalink)
axl2 Member Join Date: Oct 2008 Location: Mahone Bay, NS, Canada Posts: 35	Re: Just Got New Tubes For My DSL 100 I'm heading into Radio Shack tomorrow. I'll look for something in the 20 dollar range I guess? Not sure how much these things cost to be honest... I seen a few for 15 dollars off ebay. __________________ Marshall DSL 100 Head Marshall AVT 20- Combo Epiphone Les Paul-Seymour Duncan Pups Fender Showmaster- Seymour Duncan Pups Takamine Electric Acoustic Epiphone Acoustic Boss GE7 Ibanez DL10 Delay Ibanez TS-808

10-06-2008, 09:10 PM	#15 (permalink)
DevilsEve666 Member Join Date: Apr 2008 Posts: 30	Re: Just Got New Tubes For My DSL 100 with these things I guess price isn't always the best factor to consider...like that radio shack one that I bought was $29.99 and then i got the one from the eurotubes sight and it was 10.00 and it is excellent!! I had my amp biased in no time...

10-06-2008, 09:12 PM	#16 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 +1, get the one from Euro Tubes!

10-06-2008, 09:51 PM	#17 (permalink)
axl2 Member Join Date: Oct 2008 Location: Mahone Bay, NS, Canada Posts: 35	Re: Just Got New Tubes For My DSL 100 Wow, K guys thanks for the help. I just ordered the Multimeter on the Euro Tubes site. __________________ Marshall DSL 100 Head Marshall AVT 20- Combo Epiphone Les Paul-Seymour Duncan Pups Fender Showmaster- Seymour Duncan Pups Takamine Electric Acoustic Epiphone Acoustic Boss GE7 Ibanez DL10 Delay Ibanez TS-808

10-06-2008, 10:50 PM	#18 (permalink)
stock_hippie Senior Member Join Date: Mar 2008 Posts: 266	Re: Just Got New Tubes For My DSL 100 not getting the downloAd...is it me?

10-07-2008, 12:37 PM	#19 (permalink)
solarburnDSL50 Senior Member Join Date: Aug 2008 Location: WashingTone Posts: 108	Re: Just Got New Tubes For My DSL 100 Part of biasing your DSL is getting plate voltage too. You figure this number and you can get your correct bias number. DSL's run plate voltage from 450 to 500 with EL34's usually somewhere in between. Marshall recomends 40 to 45 bias. I set mine cooler at 36 with Tung Sol EL34B's. Example formula - 25 watts disipation divided by lets say 450 plate volts = .055 Then multiply .055 times 60 or 70% depending how hot you want to run the tubes. .055 x .6 = .033 .055 x .7 = .038. So at 60% your bias number is 33. At 70% your bias number is 38. Eurotubes didn't show how to check for voltage in the DSL vid. He just set the bias which is what you do after getting the plate voltage and crunching the numbers per the formula. He does show how with the JCM 800 vid though. __________________ DSL50 - Voodoo modded Fender Tele GT HH coil split 212 G12K-100/V30 Pedals just for the Marshall: Bad Monkey Boosta Grande Wah Aphex Xciter in loop Delay in loop

10-07-2008, 05:29 PM	#20 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 I spoke with Euro Tubes about this and this was their response: "The plate voltage is a fixed amount of voltage supplied buy your transformer to the plates of the power tubes. It’s not variable and you really don’t need to worry about it. Thanks, Eddie" fwiw

10-07-2008, 11:31 PM	#22 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 I hear ya solar but being that the dude that put out the 800 vid clip owns the company I got the response from, it stands to reason that perhaps the 800/900 series and older are different animals than the DSL/TSL's. They seem to be on the ball over there at Euro so no real reason for me to doubt their information. And I have watched the 800 clip and wondered the same thing but they told me the plate voltage didn't apply with the TSL so I didn't worry about it. Oh well, we're all learning!

10-08-2008, 12:03 AM	#23 (permalink)
axl2 Member Join Date: Oct 2008 Location: Mahone Bay, NS, Canada Posts: 35	Re: Just Got New Tubes For My DSL 100 It appears my first official thread on here has been put to good use lol __________________ Marshall DSL 100 Head Marshall AVT 20- Combo Epiphone Les Paul-Seymour Duncan Pups Fender Showmaster- Seymour Duncan Pups Takamine Electric Acoustic Epiphone Acoustic Boss GE7 Ibanez DL10 Delay Ibanez TS-808

10-08-2008, 01:28 AM	#25 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 Yeah, see my post above in describing the bias adjustments. Minute adjustments!

10-08-2008, 01:23 PM	#27 (permalink)
steelhorse Senior Member Join Date: May 2008 Posts: 1,512	Re: Just Got New Tubes For My DSL 100 Thanks!

10-08-2008, 06:31 PM	#28 (permalink)
RiverRatt Member Join Date: May 2008 Posts: 60	Re: Just Got New Tubes For My DSL 10