Bare Knuckle Pickups Forum

Forum Ringside => Guitars, Amps and Effects => Topic started by: duke84 on March 30, 2009, 12:52:53 AM

Title: Tubes help
Post by: duke84 on March 30, 2009, 12:52:53 AM
I have a Marshall TSL - 100 and i am thinking about swapping the EL34 tubes for 6L6. How big a deal is to do this and what brand of 6L6 would you recommend? Is there much difference in sound between brands? I play a combination of progressive/heavy/thrash metal.
Title: Re: Tubes help
Post by: Adam.M on March 30, 2009, 01:22:00 AM
It's not a massive deal but you can not do it yourself without some knowledge and experience and equipment but a local tech should be able to do it for not much money, and i'd suggest Svetlana Winged =C='s for 6L6's in Marshalls and thats based on what i am consistently hearing from people who's ears i trust, pretty much everyone has suggested those to me. There can be quite a difference between brands because they all make the tubes differently.

But also play with your preamp tubes... this is a great one cause you can do this yourself, the V1 tube has the most effect.
Title: Re: Tubes help
Post by: hamfist on March 30, 2009, 07:06:21 AM
Get good advice on this one. I would be amazed if you could just swap from EL34's to 6L6's as these valves have very different power needs, and different power transformers, as well as bias circuits, are usually required for such a swap.

However, some amps still have flexible enough PT's to accomodate the swap (although usually not amps "built to a price" like the TSL, though).
Title: Re: Tubes help
Post by: ailean on March 30, 2009, 02:25:24 PM
Yeah check the amp specs sheet, it might well be set up to take 6L6 already. You will probably need to re-bias the amp though (unless you are amazingly lucky).

Have a read through the Watford Valves website, they have quite good descriptions of the value qualities. I've just ordered a quad of 6L6's to give me the best cleans I can get :)

http://www.watfordvalves.com/product_detail.asp?id=1317

These have a higher power rating than a standard 6L6, but I know the intended amp can take it.
Title: Re: Tubes help
Post by: AdamB on March 30, 2009, 06:41:03 PM
I'm pretty much 100% sure that the TSL can't take 6L6's unless you get a tech to mod it
Title: Re: Tubes help
Post by: Fourth Feline on March 30, 2009, 08:41:55 PM
Yeah check the amp specs sheet, it might well be set up to take 6L6 already. You will probably need to re-bias the amp though (unless you are amazingly lucky).

Have a read through the Watford Valves website, they have quite good descriptions of the value qualities. I've just ordered a quad of 6L6's to give me the best cleans I can get :)

http://www.watfordvalves.com/product_detail.asp?id=1317

These have a higher power rating than a standard 6L6, but I know the intended amp can take it.

Rather spookily, I just mentioned the benefits / qualities of Jan / Phillips 7581As on Ian Price's "Tele Love" thread.  my favourite 6L6 variant of all time ...   :D

I echo the urge for caution in having your amp assessed for suitability / re-biased by a tech though.
Title: Re: Tubes help
Post by: ailean on March 30, 2009, 08:59:29 PM

Rather spookily, I just mentioned the benefits / qualities of Jan / Phillips 7581As on Ian Price's "Tele Love" thread.  my favourite 6L6 variant of all time ...   :D

That's good to know. I look forawdr to getting them in place then!
Title: Re: Tubes help
Post by: HTH AMPS on March 30, 2009, 10:34:21 PM
I have a Marshall TSL - 100 and i am thinking about swapping the EL34 tubes for 6L6. How big a deal is to do this and what brand of 6L6 would you recommend? Is there much difference in sound between brands? I play a combination of progressive/heavy/thrash metal.

6L6s require less heater current than EL34s, so the mains transformer will be fine.  The output transformer's primary Z won't be optimal, but should be fine - plenty of amps out there fudge the PT's primary to suit, it's really not as critical as many people would have you believe (valve amps are very forgiving).  However, just popping in a set of 6L6s in an amp set up for EL34s is asking for trouble, you'll at least want to set the amp's bias cold as it'll go and take it from there.

You'll get more bass and less crunch in the mids with 6L6s rather than EL34s.

For the styles you list, I'd go with 6550s - bigger/tighter bass, all the crunch that EL34s have and a more agressive overall tonality (plus more headroom).  Every amp I've ever put 6550s in has improved the tone.  You'll need more bias voltage, so the bias supply will need tweaked, but thats nothing a tech can't do in an hour's worth of bench time.

Title: Re: Tubes help
Post by: hamfist on March 31, 2009, 07:11:11 AM
For the styles you list, I'd go with 6550s - bigger/tighter bass, all the crunch that EL34s have and a more agressive overall tonality (plus more headroom).  Every amp I've ever put 6550s in has improved the tone.  You'll need more bias voltage, so the bias supply will need tweaked, but thats nothing a tech can't do in an hour's worth of bench time.

Good suggestion HTH.

I put JJ KT88's (very, very similar to 6550's) in the Ceriatone 2204 I used to have and liked them much more than the JJ E34L's it had in it. Tighter, more bass, more detailed treble, more headroom. Simply a more refined, modern sound.

However, I still prefer good, old stock EL34's to modern 6550's/KT88's. As I have a reasonable stock of old tubes I'll be using them for a few years I guess. If I didn't have those tubes stashed away I would definately be looking at putting modern 6550's/KT88's in my EL34 amps again.
Title: Re: Tubes help
Post by: duke84 on April 01, 2009, 02:11:41 AM
Yeah, that's pretty much what i am looking for bigger, smoother sound as compared to the one i have now which fells rather "harsh" and dirty when cranked up. The modifications shouldn't be a problem, i know someone who can help me.
Title: Re: Tubes help
Post by: hunter on April 01, 2009, 06:38:38 AM

You can always try a pair of JJ KT77, they are a direct replacement for EL34 and sound more like between EL34 and 6L6. Cleaner, more bass/treble, less fizzy mids. Will make your TSL sound less like a Marshall though.

What about selling the TSL and getting a different amp, more suited to our taste, rather than investing loads of money in tubes?
Title: Re: Tubes help
Post by: Dmoney on April 01, 2009, 06:56:42 AM
For the styles you list, I'd go with 6550s - bigger/tighter bass, all the crunch that EL34s have and a more agressive overall tonality (plus more headroom).  Every amp I've ever put 6550s in has improved the tone.  You'll need more bias voltage, so the bias supply will need tweaked, but thats nothing a tech can't do in an hour's worth of bench time.

Good suggestion HTH.

I put JJ KT88's (very, very similar to 6550's) in the Ceriatone 2204 I used to have and liked them much more than the JJ E34L's it had in it. Tighter, more bass, more detailed treble, more headroom. Simply a more refined, modern sound.

However, I still prefer good, old stock EL34's to modern 6550's/KT88's. As I have a reasonable stock of old tubes I'll be using them for a few years I guess. If I didn't have those tubes stashed away I would definately be looking at putting modern 6550's/KT88's in my EL34 amps again.

+1
my JCM800 2205 is a 50watt KT88 driven amp. it has some piggybacked resistors on the pcb which i assume effect the bias.

i'd say its an option worth checking out along with the KT77's
Title: Re: Tubes help
Post by: Alex on April 01, 2009, 11:53:37 AM
The TSL100 is one of those modern amps where the preamp has more influence over the sound than the poweramp.

Before doing any costly changes to the poweramp I would first recommend experimenting with different preamp tubes. I've just put some JJs in my 5150 and the difference is massive!

If yuo are still set on changing the poweramp tubes: I had a 50 Watt JCM900 with EL34, my bandmate had the same amp but with 6L6 (most JCM900 actually had 6L6s as I found out later). The 6L6 was a bit bluesier and nicer with clean sounds (at higher volumes!). The EL34 had more bite and was a bit more aggressive. For rock/hardrock/metal I would prefer the EL34, it has more of a "rock sound" IMO.