Bare Knuckle Pickups Forum
Forum Ringside => Guitars, Amps and Effects => Topic started by: Johnny Mac on September 08, 2012, 06:43:04 AM
-
Ive got to put some new valves in my Koch (Powertone II) as its making microphonic noises. I think that's the pre amp valves. But as they are 7 years old I thought its about time I put new valves in the pre and power amp section. Essex amp repairs recommended JJ but what about brands like Groove Tubes and also these Cyro treated valves?
-
you should get your Koch serviced on a slightly more regular basis.! wahheeeeyyy! :D
I like JJ's... It's possible to get JJ EL34's and E34L's. They actually slightly different and give slightly different amounts of power with the same B+ voltage and biased to a comparable point. I can't remember which gave more power though. I thinking its the E34L's.
-
My favourite to date, and by far, are tung sol EL34Bs.
-
Tung Sols for 12AX7 and 12AT7 and Winged =C= EL34s are my favourites.
If the tubes are seven years old then you're in for a nice surprise when you get some new ones in there and get it roaring again.
This may be useful to you, side by side reviews of preamp and power amp tubes
http://thetubestore.com/el34review.html
http://thetubestore.com/12ax7review.html
-
winged C's sound great and are very articulate and punchy, but way overpriced in the last couple years
I like the smooth and compressed tone of the shuguang el34b-str (ruby, tad, valve art, peavey, marshall) for some amps
I like the brighter electro harmonix el34's as well
jj's sound a bit dark and dull in comparison in some particular amps, but not bad
for the preamp, the NOS rft/siemens ecc83 is hard to beat, at least for distortion, but are a bit pricey
I like shuguangs as well, although they can be a bit noisy in higher gain amps
sovteks ad electro harmonix are well balanced
JJ's are good to darken up brighter and more spikey sounding amps
they are supposedly higher gain, but they atually sound cleaner
didn't try tung sols, but people seem to love them
-
I got the Winged C's for my Egnater a year or so back, and they really improved the tone, Jon. And it was already a great sounding amp.
Insert them into your Koch and I suspect everyone to come across it will be stunned into impressed silence.
-
Winged C's are great, I had them in a Koch Multitone. EH's and JJ's are good too. Like the EH's better, the JJ's were less crunchy in that amp. Svetlana's aren't bad either.
-
GT (now owned by Fender) do have a handful of exclusive designs, but by and large simply test and rebrand valves, for which you pay a considerable premium.
I'm yet to convinced that chilling and evacuated glass envelope with metal pins emminating from it to liquid N2 temperature is a great idea......
I prefer the sound (although not the price) of =C= EL34s over JJs.
I would say that the JJs probably have the edge in reliability stakes though. In my view the =C=s don't like being mechanically shocked.
For pre-amp valves I prefer the sound of the JJ-ECC803s. This valve has a reputation for microphony, but to be honest I've not had a major problem with it.
The standard EH-12AX7 is nice sounding valve, but EH had some reliability issues a couple of years ago with their spiral filament valves, so I stopped using them. I quite like the Tungsol 12AX7.
The standard JJ-ECC83s are inexpensive and generally reliable and sound OK, but I don't think are the best pre-amp valve.
-
Im a big fan of JJs for poweramps I haven't found anything that can give me the aggression I need but im still to try the tungsols but im concerned about them being overly bright as I often find the preamp valves are.
In the preamp I often go for a mix of Jan 5751 in v1 then tungsol 12ax7 in v2 then JJ ECC83s in the rest.
I find it gives a very nice full bodied tone that is fairly versatile but doesn't wimp out for heavier stuff either.
-
I absolutely love Groove Tubes EL34M power tubes. Great tone, and you can get different ratings for the amount of headroom or early tube breakup you want.
-
I absolutely love Groove Tubes EL34M power tubes. Great tone, and you can get different ratings for the amount of headroom or early tube breakup you want.
I think you can get this on any power valve from hotrox.
-
Oh :lol:
I've tried many different tubes, from =C= to JJ to EH and many others, and the GT's were far superior to all of them, IMO.
-
I'me very pleased with the Tung Sol EL34Bs in my Cornford Roadhouse. When the amp is cranked a little they have have a wonderful depth to them and produce phenomenal crunch tones. Recommended by Hotrox - I can't remember the name of the guy I spoke to but he would have been happy to talk valves all day, he was very friendly and really knew his stuff. Guy I spoke to at Watford was a rude, arrogant arse.
-
I'm glad i'm not the only one who has bad experiences with Watford. At one point I thought I was just really unlucky as everyone else seemed to love them. With that I gave them another chance and got the exact same results... :( Never again
-
I posted this on the Cornford site last year:
Having established that my Roadhouse needs new output valves I decided to have a look around the net for the best EL34s I could find. I am aware that the Roadhouse is cathode biased so had no fear of changing the valves myself. I phoned Watford Valves to ask for suggestions. I explained what I was looking for and got an extraordinary response.
I was told that the amp DID need biasing and the guy I was speaking to rattled off a list (really quickly and using technical terms I am unfamiliar with) of other checks and tests that needed to be done by a qualified tech only. If I had any problems with their valves I would need to provide confirmation from a tech with verifiable qualifications that these checks had been carried out. Failure to do this would mean any warranty was invalid. I was reeling when I finished the call. The guy's manner was brusque and patronising. Or downright rude if I think about it.
I then phoned Hot Rox. I can't remember the guy's name but his attitude was the polar opposite of Watford. He agreed that the amp didn't need biasing and we then had a longish conversation about the rival merits of various EL34s and his own preferences. A helpful and friendly guy.
My overall feeling from talking to Watford was that they were totally on the defensive and wanted to make it perfectly clear that if their valves blew up it wasn't their problem.
In sorting out the fault with the amp I have had great support from Martin Kidd again. Top man. I've also had some great advice from fellow forum member Marc. Thanks a lot to both of you.
I've decided to go with Tung Sol 34Bs. I'll let you know how they sound in due course. Think twice about dealing with Watford Valves.
-
I bet finding a tech with actual verifiable qualification in VALVE technology is pretty difficult. I don't think they teach that in school any more, and at best I imagine it would be a footnote on any electronics course.
What watford may have said about checking the bias in cathode biased amps may have been correct. I think they should technically be checked on the off chance you get a set of valves that operate outside the expectations covered by the design of the amp. Still, no need to be rude about it and rebiasing the amp would mean swapping out a pretty chunky fixed resistor, which is a bit tougher than using a bias pot. You'd also probably have a slight pain getting a meaningful bias reading. Bit of a can of worms. I'm sure Martin Kidd designed the amp to bias up ok within a fairly decent tolerance without the need for all that work, you just can't design for that freak set of valves that draws some wacky level of current. maybe it's a moot point.
EDIT: I've also had the same issue with Watford Valves and won't use them any more. Additionally, I can't recommend Tube Amp Doctor either... I've had TERRIBLE service from them, and been charged for a matching service that wasn't even carried out. I'd say WORSE than watford valves.
Tube-Town.de is cool. nuff said! I like that store and if you get an issue with a miss matched valve they are usually happy to help.
-
I use Mullard reissue el34 valves which sound decent to me. I used JJ before, and they were fine too, a bit less nice maybe.
-
Dmoney - appreciate your input. I double checked with Martin and he assured me that the amp did not need biasing and also that there was no mechanism in the amp to adjust the bias with. What would happen if a set of valves in a cathode biased amp did draw a wacky level of current ? I'm no technician so I rely on the advice of those that know.
I got the Cornford BECAUSE it was cathode biased as I don't know how to do this myself and I didn't want to have to pay a tech to do it for me. To have Watford insist that the amp had to be taken completely to bits was disconcerting to say the least. The whole thing with Watford was basically that they were saying that they would under no circumstances replace a set of duff valves because it was bound to be my fault if they blew/didn't work. I think it was Derek I spoke to. I spoke to him many years ago and he was okay if a little patronising. That last occasion he was deeply unpleasant and told me that Martin Kidd was an idiot who didn't know what he was talking about. I will not miss an opportunity to advise people not to deal with him.
-
I've decided to go with Tung Sol 34Bs. I'll let you know how they sound in due course. Think twice about dealing with Watford Valves.
Good choice! I find them to have a sound that is sort of like the combined strengths of 6l6 and el34, none of the/minimised weaknesses. Mid grind, punch and grunt of 34, tight low end of 34 but somewhere between there and 6l6 in 'size'/depth, and smoother, richer, more detailed top end than 34s, but not so stabby or spiky as 6l6s can be. Zero fizz or harshness (all in pittbull CL100, which is an early model that can take 6L6s, which I've done, so my observations are 34s vs TS34Bs vs 6l6 in the same amp (but only one amp)).
Only dealt with watford valves very briefly, knew exactly what I wanted, no discussion, so no comment, but the chaps I've spoken with at hotrox were as you describe. I go there unless I cant get what I want from there.
-
Richard - My main point was it sounds like watford valves were just being really pedantic.
-
cathode bias is VERY forgiving - I really wouldn't give it a second thought of checking the bias in such an amp.
-
Thanks for all the advise :) I've had a read up on Tung Sol EL34b's. They sound like a good choice.
-
Let us know how you get on with them.
-
I won't make any suggestions on specific brands of valves but will chuck in another +1 for Hot Rox! :D
-
I'm a huge fan of the Groove Tube EL34-LS tubes...... These are a 30 watt tube and your amp would need to be re biased. They are not the same tube as the JJ ones..... JJs are 25watters...... The LSs have big tight bottom, with a real nice tone.....
Winged Cs are my next fav...