Does anyone know if the same will apply to the 30 watt version? I can't find any TSA30 bias instructions anywhere! Even when I open the amp up - I can't even see test points - but I do see an adjustment pot. I assume since the TSA30 runs off of 6L6 tubes that -30V DC might not be the same for me.
You might try checking voltage across the output transformer leads (power amp side, not speaker side). make note of where that adjustment pot is, then take a voltage across yellow and red, then move the pot and see if the reading changes. Check the other two leads for a comparable reading... it may be a balance pot. Keep looking for a schematic.
Thank you for the informative video! I've heard the JJ 6V6 tubes have larger plates than a true 6V6 does, and that as a result they sound more like 6L6 tubes. Has that been your experience since you switched to JJ 6V6 tubes? What differences did you hear?
Mr. Del Valle - honestly differences different tubes can be here or there. Differences in good tubes vs bad tubes is of course considerable but when guys say “this or that tube made my amp sound SO MUCH different” they’re full of crap imo. It’s even hard to tell in the Rebel 30 by Egnater that allows you to switch between 6V6 and EL84s. EL84 a little brighter, firmer in response and crispy compared to the softer 6V6 tubes. It’s a small difference but enough that I know I prefer EL84 amps. But again, different enough that I sprung for a Fender Supersonic so when I’m in the mood for that sound, I’ve got it. I’d be hard pressed to hear the difference of one 6V6 vs any other brand of the same type. I hear small differences in GT preamp tubes, they seem to have a little more midrange. And I usually hear a very nice difference in swapping 12AX7s with 12AT7s in my higher gain amps.
@@oldguyjammin9732 I appreciate the reply. I've always been a fan of JJ power tubes, for their durability and long life. Glad to know they work (and fit). I'm using EH 6V6 now, but I'd like to try the JJ 6V6S tubes on my next swap out.
I have just changed original power tubes and I have a pair of new JJs 6VS inside and yes, I can confirm, amp sounds now pretty close to 6L6, more lower and higher end, sounds more fenderish.
I have changed all tubes in my TSA15 amp and did not biasing, cause I read that I do not have to that for this amp. Am I risking something? I general, what I can say - after the change of preamp tubes (for JJ ECC83S/12AX7) and power tubes (for paired JJ 6V6S), and I have to say, big WOW! :) Really, I would never expect such a big tone difference! I always fought I have very good sounding amp, but now, I have a killing machine! :) Significant sound change, lot s of muddiness and dirt disappeared, now it has a strong low end and clear highs, with less mids, 100% top class "fender" sounding amp. Super super clean. Somebody could miss mid frequencies and dirt, but I much prefer adding gain (by pedals) instead of removing it (which could be mission impossible :) )
That’s great man! Thanks for taking the time to post your findings, super cool. If it sounds great I’d just leave it alone. It does have a bias adjustment pot and test point but I don’t think ‘proper biasing’ is as important as I used to think. It’s probably close to mathematical perfection but your amp will still work, and work FINE a ways off of that target of 70% saturation value - if it sounds good, IT IS GOOD \m/
My gosh, seems like a goof somewhere but... but.... but, how does it sound? I read all the time that techs will often bias an amp based purely on tone... no instruments. Angus Young has to replace tubes every performance cause they’re biased HOT while John Petrucci replaces tubes ONCE a tour cause they’re on the cooler side. Up to you dude :) It’s nice knowing that it’s somewhere’s “right” though ;-)
Great, informative video. I have a question for you sir; is it possible to swap filter caps in this amp with much more quality/boutique caps such as Sozo's? Can we benefit in sound quality by using quality caps? Thank you and greeting from Istanbul/Turkey.
I’m sure you could swap same size and value caps, but I’m not sure how great the difference will be without swapping out many of the other circuit parts too. I wouldn’t think too much with just caps... Guys often talk about how this tube, or that tube made “brought my amp to life” when it was probably just a ‘new’ tube versus one that needed to replaced anyway, lol. I’ve swapped a lot of tubes and am never really sure I hear any difference at all...except replacing an old and worn out one with a fresh one. WOW.. Turkey - Very Cool! Thank you
One more question. I have a couple of 5881 tubes. Size is about the same as the 6V6's. I know they are 6L6's. I googled this question and could not find an answer. Will these 5881's blow or damage the TSA15H? Can it be biased for them? Thanks.
www.ampvalves.co.uk/5881-6l6gc-valve-differences/ So it sounds like you’re wanting to move in the safer direction anyway 6L6 > 5881 I’d cool off the bias a bit. See if you can find a recommended bias voltage for 5881 tubes. Sounds like you’ll have less clean headroom and earlier break up with the 5881 tubes. Hard to tell from the article I attached but it sounds like the only problem you may have is ‘red plating’ the 5881s unless you lower the bias... not to big a deal, you’ll just have to replace them sooner.
What happens if you don't bias the tubes? I was told this was a plug-n-play amp. ie. no biasing required. But I changed my tubes and now there's a buzzing noise. Could this account for the noise? The volume of the noise doesn't increase when turned up - it's always the same level regardless of how loud the amp is turned up.
The noise is probably in one of your pre-amp tubes, not sure what you changed out though. You could swap out one at a time with the old ones until the noise disappears. Biasing ensures you’re NOT going to red plate your tubes (too hot) it’s an efficiency thing and really not as important as I used to think. I bias my amps on the cooler side just cause I like the tone better, less fizzy imo. Introducing new tubes could definitely account for new noise. If it stays at the same level it could be an effects loop tube. I don’t recall the tube layout in that amp but maybe the third one away from the input jack. You could rotate them into the first slot and see if volume changes end up affecting the noise.
@@oldguyjammin9732 Thanks for the reply. There are no FX loop tubes. The FX loop isn't a proper FX loop. It's just an out/in after the Tube Screamer circuit. I will check the pre amp tubes though. I meant to say it's a lot more noisy on the 5W setting than 15W for some reason. Not sure if that could help identify the cause of the noise. Thanks again
@@oldguyjammin9732 I swapped the preamp tubes around and it is slightly quieter. But still too noisy on 5W mode. Any idea what that could be? Could it just be the switch or whatever circuitry is engaged when switched?
@@Dani-El. - noise is really hard to track down, it could be some dirt in a pot... How about putting the old tubes back in? See what happens. The bizarre thing is that the noise is louder in the 5 watt mode, it should be the other way around I’d think. Get some contact cleaner and wash out the tube sockets, pots and jacks - it sometimes does wonders.
So, you showed putting the alligator clips to two test pins before attaching your meter, but then glossed over the next steps. All of a sudden you still have the red clip on the original probe, but you have moved the other probe to attach to the chassis(?) Why? The whole gist of your video is the testing and biasing, which you gloss over without showing the connections and reason for them or even a good view of the adjustment trim pot. I am not confident that I can do this correctly.
Yes, sorry for the confusion but you’ll be fine. The critical test point is that upper pin or PR1, the other pin is just ground so it’s just easier to ground your other lead to the chassi, but it’s the same thing. Ground is ground is ground :) I showed where the pot is, just not adjusting it. Still, if you’re at all uncomfortable better to get some help.
These look pretty well built!
Thank you! I'm going to service mine in the next weeks. Good instructions how to bias the tubes.
Btw. Kaputt is out of my native lingo. Gute Nacht 😎
That’s awesome, really made my night... Kaputt!! Who knew :) Cheers!
Does anyone know if the same will apply to the 30 watt version? I can't find any TSA30 bias instructions anywhere! Even when I open the amp up - I can't even see test points - but I do see an adjustment pot.
I assume since the TSA30 runs off of 6L6 tubes that -30V DC might not be the same for me.
You might try checking voltage across the output transformer leads (power amp side, not speaker side). make note of where that adjustment pot is, then take a voltage across yellow and red, then move the pot and see if the reading changes. Check the other two leads for a comparable reading... it may be a balance pot. Keep looking for a schematic.
Thank you for the informative video! I've heard the JJ 6V6 tubes have larger plates than a true 6V6 does, and that as a result they sound more like 6L6 tubes. Has that been your experience since you switched to JJ 6V6 tubes? What differences did you hear?
Mr. Del Valle - honestly differences different tubes can be here or there. Differences in good tubes vs bad tubes is of course considerable but when guys say “this or that tube made my amp sound SO MUCH different” they’re full of crap imo. It’s even hard to tell in the Rebel 30 by Egnater that allows you to switch between 6V6 and EL84s. EL84 a little brighter, firmer in response and crispy compared to the softer 6V6 tubes. It’s a small difference but enough that I know I prefer EL84 amps. But again, different enough that I sprung for a Fender Supersonic so when I’m in the mood for that sound, I’ve got it. I’d be hard pressed to hear the difference of one 6V6 vs any other brand of the same type. I hear small differences in GT preamp tubes, they seem to have a little more midrange. And I usually hear a very nice difference in swapping 12AX7s with 12AT7s in my higher gain amps.
@@oldguyjammin9732 I appreciate the reply. I've always been a fan of JJ power tubes, for their durability and long life. Glad to know they work (and fit). I'm using EH 6V6 now, but I'd like to try the JJ 6V6S tubes on my next swap out.
I have just changed original power tubes and I have a pair of new JJs 6VS inside and yes, I can confirm, amp sounds now pretty close to 6L6, more lower and higher end, sounds more fenderish.
I have changed all tubes in my TSA15 amp and did not biasing, cause I read that I do not have to that for this amp. Am I risking something?
I general, what I can say - after the change of preamp tubes (for JJ ECC83S/12AX7) and power tubes (for paired JJ 6V6S), and I have to say, big WOW! :) Really, I would never expect such a big tone difference! I always fought I have very good sounding amp, but now, I have a killing machine! :) Significant sound change, lot s of muddiness and dirt disappeared, now it has a strong low end and clear highs, with less mids, 100% top class "fender" sounding amp. Super super clean. Somebody could miss mid frequencies and dirt, but I much prefer adding gain (by pedals) instead of removing it (which could be mission impossible :) )
That’s great man! Thanks for taking the time to post your findings, super cool. If it sounds great I’d just leave it alone. It does have a bias adjustment pot and test point but I don’t think ‘proper biasing’ is as important as I used to think. It’s probably close to mathematical perfection but your amp will still work, and work FINE a ways off of that target of 70% saturation value - if it sounds good, IT IS GOOD \m/
@@oldguyjammin9732 Yes, it does sound fine without biasing, so I have no worries anymore ;) :) Thanx!
I just biased one. I used a bias probe had to turn the bias adjustment pot all the way down just to get 60%. 330vdc on the plates 24 ma draw.
My gosh, seems like a goof somewhere but... but.... but, how does it sound? I read all the time that techs will often bias an amp based purely on tone... no instruments. Angus Young has to replace tubes every performance cause they’re biased HOT while John Petrucci replaces tubes ONCE a tour cause they’re on the cooler side. Up to you dude :) It’s nice knowing that it’s somewhere’s “right” though ;-)
Great, informative video. I have a question for you sir; is it possible to swap filter caps in this amp with much more quality/boutique caps such as Sozo's? Can we benefit in sound quality by using quality caps? Thank you and greeting from Istanbul/Turkey.
I’m sure you could swap same size and value caps, but I’m not sure how great the difference will be without swapping out many of the other circuit parts too. I wouldn’t think too much with just caps... Guys often talk about how this tube, or that tube made “brought my amp to life” when it was probably just a ‘new’ tube versus one that needed to replaced anyway, lol. I’ve swapped a lot of tubes and am never really sure I hear any difference at all...except replacing an old and worn out one with a fresh one. WOW.. Turkey - Very Cool! Thank you
One more question. I have a couple of 5881 tubes. Size is about the same as the 6V6's. I know they are 6L6's. I googled this question and could not find an answer. Will these 5881's blow or damage the TSA15H? Can it be biased for them? Thanks.
www.ampvalves.co.uk/5881-6l6gc-valve-differences/
So it sounds like you’re wanting to move in the safer direction anyway 6L6 > 5881 I’d cool off the bias a bit. See if you can find a recommended bias voltage for 5881 tubes. Sounds like you’ll have less clean headroom and earlier break up with the 5881 tubes. Hard to tell from the article I attached but it sounds like the only problem you may have is ‘red plating’ the 5881s unless you lower the bias... not to big a deal, you’ll just have to replace them sooner.
What happens if you don't bias the tubes? I was told this was a plug-n-play amp. ie. no biasing required.
But I changed my tubes and now there's a buzzing noise. Could this account for the noise?
The volume of the noise doesn't increase when turned up - it's always the same level regardless of how loud the amp is turned up.
The noise is probably in one of your pre-amp tubes, not sure what you changed out though. You could swap out one at a time with the old ones until the noise disappears. Biasing ensures you’re NOT going to red plate your tubes (too hot) it’s an efficiency thing and really not as important as I used to think. I bias my amps on the cooler side just cause I like the tone better, less fizzy imo. Introducing new tubes could definitely account for new noise. If it stays at the same level it could be an effects loop tube. I don’t recall the tube layout in that amp but maybe the third one away from the input jack. You could rotate them into the first slot and see if volume changes end up affecting the noise.
@@oldguyjammin9732 Thanks for the reply. There are no FX loop tubes. The FX loop isn't a proper FX loop. It's just an out/in after the Tube Screamer circuit.
I will check the pre amp tubes though. I meant to say it's a lot more noisy on the 5W setting than 15W for some reason. Not sure if that could help identify the cause of the noise. Thanks again
@@Dani-El. - that’s weird, it should be quieter on the 5W mode for sure. Rotate those preamp tubes and see what happens.
@@oldguyjammin9732 I swapped the preamp tubes around and it is slightly quieter. But still too noisy on 5W mode. Any idea what that could be?
Could it just be the switch or whatever circuitry is engaged when switched?
@@Dani-El. - noise is really hard to track down, it could be some dirt in a pot... How about putting the old tubes back in? See what happens. The bizarre thing is that the noise is louder in the 5 watt mode, it should be the other way around I’d think. Get some contact cleaner and wash out the tube sockets, pots and jacks - it sometimes does wonders.
Hello there! I have a request for you. Could you send me a diagram of this amplifier? ibanez tsa15h-u
Sorry, I don’t have a diagram but thanks for coming by!
You can google the instruction manual which has a diagram included.
So, you showed putting the alligator clips to two test pins before attaching your meter, but then glossed over the next steps. All of a sudden you still have the red clip on the original probe, but you have moved the other probe to attach to the chassis(?) Why? The whole gist of your video is the testing and biasing, which you gloss over without showing the connections and reason for them or even a good view of the adjustment trim pot. I am not confident that I can do this correctly.
Yes, sorry for the confusion but you’ll be fine. The critical test point is that upper pin or PR1, the other pin is just ground so it’s just easier to ground your other lead to the chassi, but it’s the same thing. Ground is ground is ground :) I showed where the pot is, just not adjusting it. Still, if you’re at all uncomfortable better to get some help.