I've got a Hughes & Kettner Tube 50 combo which currentley uses 2, EL34 power tubes. The distortion on this amp has a very, very harsh, brazen quality to it. I've had the amp looked at twice and it's all in working order. I just read on the Eurotubes site where Bob will sometimes substitute 6L6GC's in place of EL34's in Marshall 900's. He said this add's bass and will smooth out the mid's and highs. Sounds like what the H&K need's. Anybody ever try this substitution with their amp? Thanks.
Ever use 6L6GC's in place of EL34's?
- Thread starter Mike M.
- Start date
OUTLAW1969
New member
Re: Ever use 6L6GC's in place of EL34's?
Gives you a nice "chunky , beefy" tone, I like them over EL-34's. But that is only my personal preference.
If you do it, remember to re-bias your amp.
Gives you a nice "chunky , beefy" tone, I like them over EL-34's. But that is only my personal preference.
If you do it, remember to re-bias your amp.
Re: Ever use 6L6GC's in place of EL34's?
I have a Peavey XXX. It can use a 6l6 or El34. It is my understanding that the 6's give you more cleans at higher volumes and stretches the highs and lows a bit, and makes the the lows tighter. I am switching to the El34 to fing out how it sounds. I have heard it said that the EL34 makes the amp warmer and more personality. These are things I've read and heard. It could be the type of tubes in your amp or there age too, it may be time to replace them? There are diffenent models of EL34 as well as manufacturers. Grooves tubes delineate the different models by thier characteristics. They have models such as EL34L,EL34S, etc. Be care though, some EL34s might not work without modding. For example, if I were to use the EL34L, JJ's, I would have to change my grid resister to 700ohms.
I have a Peavey XXX. It can use a 6l6 or El34. It is my understanding that the 6's give you more cleans at higher volumes and stretches the highs and lows a bit, and makes the the lows tighter. I am switching to the El34 to fing out how it sounds. I have heard it said that the EL34 makes the amp warmer and more personality. These are things I've read and heard. It could be the type of tubes in your amp or there age too, it may be time to replace them? There are diffenent models of EL34 as well as manufacturers. Grooves tubes delineate the different models by thier characteristics. They have models such as EL34L,EL34S, etc. Be care though, some EL34s might not work without modding. For example, if I were to use the EL34L, JJ's, I would have to change my grid resister to 700ohms.
aleclee
Major General GAS
Re: Ever use 6L6GC's in place of EL34's?
I think your money would be better spent on preamp tubes.
I think your money would be better spent on preamp tubes.
- The HK's OD is created in the preamp, not the power amp. In preamp-dominated circuits, changing power tubes doesn't make a big impact on the character of the OD.
- Preamp tubes are generally cheaper than power tubes...
- ...Especially since you don't need to rebias when changing preamp tubes
jon
New member
Re: Ever use 6L6GC's in place of EL34's?
Well said, you took the words out of my mouth.
Try changing the pre-amp valves to good qualty units, JJ's seem to be a fave, get ones that have lower gain rating.
Power amp distortion only comes in a LOUD volumes, and, if it's anything like my marshall, you can't just put 6L6's in, you have to change some resistors.
aleclee said:
Well said, you took the words out of my mouth.
Try changing the pre-amp valves to good qualty units, JJ's seem to be a fave, get ones that have lower gain rating.
Power amp distortion only comes in a LOUD volumes, and, if it's anything like my marshall, you can't just put 6L6's in, you have to change some resistors.
aleclee
Major General GAS
Re: Ever use 6L6GC's in place of EL34's?
IMO, JJ ECC83's are great tubes, esp for the money.
Though they're not cheap ($22-25 each from what I've seen), the GT 12AX7M's are very good for smoothing things out, as well. Putting one in V1 took the graininess from my Rivera's edge-of-distortion tones.
I use the GTs in positions where I can hear a difference and JJs for everything else.
Also, some tube amps use diode clipping to achieve higher-gain tone without adding gain stages. I dunno if your HK is one of 'em but, if so, it may be hard to achieve the tone you want simply by swapping preamp or power tubes.
IMO, JJ ECC83's are great tubes, esp for the money.
Though they're not cheap ($22-25 each from what I've seen), the GT 12AX7M's are very good for smoothing things out, as well. Putting one in V1 took the graininess from my Rivera's edge-of-distortion tones.
I use the GTs in positions where I can hear a difference and JJs for everything else.
Also, some tube amps use diode clipping to achieve higher-gain tone without adding gain stages. I dunno if your HK is one of 'em but, if so, it may be hard to achieve the tone you want simply by swapping preamp or power tubes.
D
DeadSkinSlayer3
Guest
Re: Ever use 6L6GC's in place of EL34's?
JJ 12AX7's are cheap, like 8 bucks each, but I found I hated them compared to EH's. The halfed my gain, and the tone was less raw and punchy.
JJ 12AX7's are cheap, like 8 bucks each, but I found I hated them compared to EH's. The halfed my gain, and the tone was less raw and punchy.
Re: Ever use 6L6GC's in place of EL34's?
I like the electro-harmonix tubes myself, either that or some older Sovtec ... but something to try also, 12ax7,12ay7,12at7,and 12ay7 (and I think there is another that I forget) are all inter changeable, only their gain changes, 12ax7 being the highest, I forget the gain order on the others, but any amp site will have them listed. Depending on how many preamp tubes you have you can stagger the gain of the tubes; run a lower gain tube first (V1) and then a higher one, then the highest toward the end. That will tend to smooth out the distortion, if you have more than enough then that's something to try as well, note it will decrease your overall all maximum amount of distortion, but if you have more than what you use, and want to get away from the heavy metal buzzy fuzzy harmonics in the distortion that might be something to try as well.
I like the electro-harmonix tubes myself, either that or some older Sovtec ... but something to try also, 12ax7,12ay7,12at7,and 12ay7 (and I think there is another that I forget) are all inter changeable, only their gain changes, 12ax7 being the highest, I forget the gain order on the others, but any amp site will have them listed. Depending on how many preamp tubes you have you can stagger the gain of the tubes; run a lower gain tube first (V1) and then a higher one, then the highest toward the end. That will tend to smooth out the distortion, if you have more than enough then that's something to try as well, note it will decrease your overall all maximum amount of distortion, but if you have more than what you use, and want to get away from the heavy metal buzzy fuzzy harmonics in the distortion that might be something to try as well.
Gearjoneser
Gear Ho
Re: Ever use 6L6GC's in place of EL34's?
If you change power tube type, make sure to contact the manufacturer to find out for sure that it can be done. Some amps can, some can't. Also, you can't judge whether or not you like EL-34's or 6L6's by hearing them in the same amp. Certain designs sound better with EL-34's and others sound best with 6L6's.
I agree with the others about experimenting with preamp tubes. It's very likely that your amp came with 12AX7A's, which are harsh and brazen. They use them because they're the cheapest and reliable. For clean toned amps I like JJ's but for versatile amps or highgain amps, I like the GT 12AX7C's and Sovtek 12AX7LPS. I also like the GT12AX7M, but even those can get pretty muddy on highgain. I'd say to click the link in my signature and order 3 GT12AX7C's. $14 a piece, but killer.
If you change power tube type, make sure to contact the manufacturer to find out for sure that it can be done. Some amps can, some can't. Also, you can't judge whether or not you like EL-34's or 6L6's by hearing them in the same amp. Certain designs sound better with EL-34's and others sound best with 6L6's.
I agree with the others about experimenting with preamp tubes. It's very likely that your amp came with 12AX7A's, which are harsh and brazen. They use them because they're the cheapest and reliable. For clean toned amps I like JJ's but for versatile amps or highgain amps, I like the GT 12AX7C's and Sovtek 12AX7LPS. I also like the GT12AX7M, but even those can get pretty muddy on highgain. I'd say to click the link in my signature and order 3 GT12AX7C's. $14 a piece, but killer.
Re: Ever use 6L6GC's in place of EL34's?
the old chinese tubes are nicer than the newer ones but the chinese are a wamer tube than most of the russian. the jj tubes are nice as well, the ecc83 has a nice thick mid range.
i havent tried the m but when i was at brunos shop he didnt think they sounded as good as the old mullards by a long shot. still a good tube though i havent play with them much.
what kent is talking about is good as well. in general a 12ax7 has more gain than a 12at7 which has more than a 12au7, but they all have different characteristics. a 12at7 might have a cleaner brighter tone with a little less gain, where a 12au7 has a more balanced tone but with much less gain. ive heard that in some amps it isnt a good idea to use a 12ay7 but that might only be in the phase inverter. i bought three 12ay7's and they all were microphonic to some degree, one wasnt bad but one was horrible so i kinda gave up on em. they are kinda around a 12at7 for output as far as i know
the old chinese tubes are nicer than the newer ones but the chinese are a wamer tube than most of the russian. the jj tubes are nice as well, the ecc83 has a nice thick mid range.
i havent tried the m but when i was at brunos shop he didnt think they sounded as good as the old mullards by a long shot. still a good tube though i havent play with them much.
what kent is talking about is good as well. in general a 12ax7 has more gain than a 12at7 which has more than a 12au7, but they all have different characteristics. a 12at7 might have a cleaner brighter tone with a little less gain, where a 12au7 has a more balanced tone but with much less gain. ive heard that in some amps it isnt a good idea to use a 12ay7 but that might only be in the phase inverter. i bought three 12ay7's and they all were microphonic to some degree, one wasnt bad but one was horrible so i kinda gave up on em. they are kinda around a 12at7 for output as far as i know
