2. amps-preamps
  3. 139214-112482

Problem related to Push-Pull or EL34?

Hej

I have compared my EL84 amp with an EL34 amp and what strikes me is that the EL34 amp is boomy. I know that my room has a problem in the bass region and it’s like the E34 amp makes this worse. So why is that? Both are Push-Pull, but my EL84 amp has got the original capacitors replaced to “ultrafast” capacitors. So this makes me wonder if there is any truth in what I've heard: 

  1. ...the Push-Pull design in itself increases the bass and makes the sound a little boomy.

  2. ...you can counteract this by replacing capacitors to “ultrafast” capacitors.

  3. ...EL34 tubes by design emphasis bass frequencies.

This makes me very frustrated because I really like this EL34 amp (LM EL34IA) except for this bass problem. The amp is in my budget range and I need the 40W it gives (which means Push-Pull).

Any thoughts?

simna

Showing 5 responses by jond

jond's avatar
jond
6,063 posts
 
I have no idea what I have no idea what constitutes an "ultra-fast capacitor" but it's unlikely caps are the issue as stated by others above. Also you don't actually need to understand damping factor, just the different output taps and use the one that sounds better. lowrider gives you good advice on trying better tubes likely the LM branded tubes are a cost effective option from China, better tubes are out there.


Curious about your Tube Technology Unisis Signature amp, I used to own the Tube Technology Fusion CD64 cd player and absolutely loved it. Sadly it died but based on that listen your "old" amp may in fact be a better amp that the LM amp you're considering.

Last thing did you try moving the speakers around to compensate for that boominess?
jond's avatar
jond
6,063 posts
 
@simna I can understand your frustration but have you tried reaching out to Tube Technology?
jond's avatar
jond
6,063 posts
 
Oh ok I saw their website was still up but hard to tell if they were still in business. Are you in the US or elsewhere? If you are in the US, or even not, perhaps try reaching out to Zia Faruqui through Manley? I corresponded with him once years back about getting my CD player fixed but ultimately balked at sending it back to him in England.
jond's avatar
jond
6,063 posts
 
@simna Yes he answered my email this was some time ago maybe about 4-5 years ago. I have since changed my email and don’t have the correspondence any longer but it was the Tube Technology contact email; contact@tubetechnology.co.uk so I don’t know if it’s still active but worth a try.

Also I was just reading the owners manual of your amp online and this statement jumped out at me:

If your dealer cannot offer this re-tubing service it is possible to fit a replacement tube andadjust the bias yourself with the aid of a custom TT Bias Meter available from anauthorised Tube Technology dealer.


Does an everyday bias meter work on the amp or do you need this custom unit? Are you able to bias at all?
jond's avatar
jond
6,063 posts
 
@lowrider is correct those measurements are totally fine and if you think your amp sounds better than LM I would say keep it and be happy.
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