Author Topic: Re-Valving my AC30 (Read 3033 times)

ryanverbena · « **on:** October 25, 2006, 03:53:07 AM »

hi, i have a new ac30cc2 and i have read that they sound much better with new valves. I have some EI elite gold pins el84's for the power amp and i was just wondering if i would have to bias the amp before i put them in? I ask this coz i did change them over and the amp kept cutting out? I was wondering if i had to bias it or maybe one of the valves is faulty

fps_dean · « **Reply #1 on:** October 25, 2006, 08:12:22 AM »

Nope you can just drop those in.

However, everything I read about the Ei EL84s says that they sound really good but won't take the heat in an AC30. You can probably compensate by setting the output bias to warm and leaving it there and that will add a few extra volts so they shouldn't give you any problems. They arc pretty fast with low-mid voltages though.

ryanverbena · « **Reply #2 on:** October 25, 2006, 10:18:08 AM »

so it should be a bad valve that is making it cut out? Also, is there any el84's in particular you'd recommend

fps_dean · « **Reply #3 on:** October 25, 2006, 08:02:27 PM »

Yes I think if this started when you put the Ei EL84s in, it's a safe bet that's why it's cutting out.

To make a long story short, I brought my AC30 to a tech, not knowing it was cathode or what cathode was at the time. He gave me a new quad of tubes and charged me $80 for them and $80 for labor. Probably thought he was srewing me charging $80 labor for 5 minutes of actual work.
A few years later my friend gave me JJ EL84s and when I was installing them, I realied that he gave me RCA Blackplates. I've always sworn my AC30 sounds a whole lot better than any of the others I have played and know I know why. I tried the JJs anyway and they sounded horribly thin especially in comparison, and the RCAs have a good amount of use on them and still sound much better.

If you can find any NOS RCAs that are affordable (not blackplates because they're mad expensive), those are always good. For new tubes, I would be willing to try the Electro Harmonix. They are supposed to take the heat well and are the lowest noise of all the current offerings. The Eis may work fine for you with the amp set to warm instead of hot too.

What I would suggest, is RFT EL84s. I use their preamp tubes and they sound great. I never had any original Mullards, but I have read countless reviews that have stated the RFT preamp tubes sound exactly like original Mullards and cost a fraction the price because they aren't too widely known. If their preamp tubes say anything about their power amp tubes, then this is a great deal and a no brainer.

http://www.thetubestore.com/nos-6bq5.html (they will ship overseas too).

JJretroTONEGOD · « **Reply #4 on:** October 26, 2006, 03:55:19 PM »

The thing with valve amps is that you have to find the right valve sound for the guitar and speaker, it KEY to finding a perfect tone. As there are 100's of different makes! if not 1000's of tubes. It's a first to hear bad words about JJ Tesla tubes, never heard that before. : s

Bob Johnson · « **Reply #5 on:** October 27, 2006, 05:24:17 PM »

I think there's another thread with exactly the same content elsewhere on the forum but why not email Watford valves. You'll get a really informed opinion and all the help you need. They see a far greater range of valves (tubes) than any of us do individually and I feel sure you'll get an honest objective result from them.

HTH AMPS · « **Reply #6 on:** October 28, 2006, 12:15:27 AM »

my personal fave for AC30s are the Russian-military EL84s that get sold on ebay for next to nowt. I bought a dozen of them for something silly like £16 - they are louder & tighter than the JJs and EIs (cr@p imo) I tried and also have an aggressive midrange that suits the AC30 character very well.

being that they are a military spec valve, they hold up in AC30s remarkably well too.

:twisted:

fps_dean · « **Reply #7 on:** October 28, 2006, 08:56:11 AM »

^^^ Who makes them? Or do they not have a company title on them? Military grade tubes DO take abuse better.... however NOS tubes (like those RFTs I linked for example) will take a lot more abuse than current military grade tubes as well.

HTH AMPS · « **Reply #8 on:** October 28, 2006, 10:20:36 PM »

Quote from: fps_dean

^^^ Who makes them? Or do they not have a company title on them? Military grade tubes DO take abuse better.... however NOS tubes (like those RFTs I linked for example) will take a lot more abuse than current military grade tubes as well.

not sure which Russian factory they were made in, I believe they are Russian military surplus from the 80s not current production. here's a link to them...

http://cgi.ebay.co.uk/EL84-7189A-6BQ5-Tubes-New-Set-of-4_W0QQitemZ300041448408QQihZ020QQcategoryZ14947QQrdZ1QQcmdZViewItem

:twisted:

fps_dean · « **Reply #9 on:** October 29, 2006, 05:56:59 AM »

^^ Wow thanks. Those are super cheap. If they are at least usable (where I found many of the current EL84s not usable by my standards), then they are a cheap way to go and I could have backup sets ready to go as well.