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EL34 UL PP Transformer

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ruffrecords

ruffrecords

Member
Joined 2007
customtubeconsoles.com
#1
I plan to build a classic EL34 UL PP amp. One of the big questions is which output transformer to use. I know this has been asked before but the most recent thread I can find is 4 years old and a lot can happen in the world of transformers in that time. I am in the UK so European suppliers would be preference but not essential. I am aware of the Sowter offering but that is a little expensive for my tastes. I am looking for something of reasonable quality that is not too expensive, i.e. good value for money.

Recommendatiion?


Cheers

Ian
 
#3
Hello Ian,
Since you live in the UK you probably allready know about this:
Valve Push-Pull Output Transformers
I ordered a pair of OPT from him. He was helpful and nice to deal with.
I bought the "Super 20-30W" VT1041. And now I notice that he also has a
"Ultra" version, suppoused to be better. I haven't tried mine yet, so I cant say
anything about how they perform.
I seem to remember that they are made by Danbury Electronics.

Rolf
 
#4
roren said:
Hello Ian,
Since you live in the UK you probably allready know about this:
Valve Push-Pull Output Transformers
I ordered a pair of OPT from him. He was helpful and nice to deal with.
I bought the "Super 20-30W" VT1041. And now I notice that he also has a
"Ultra" version, suppoused to be better. I haven't tried mine yet, so I cant say
anything about how they perform.
I seem to remember that they are made by Danbury Electronics.

Rolf
Click to expand...


Thanks for the Rolf. I have used Danbury in the past for mains transformers. I'll check them out.

Cheers

ian
 
#12
ruffrecords said:
I plan to build a classic EL34 UL PP amp. One of the big questions is which output transformer to use.

I am in the UK so European suppliers would be preference but not essential. I am aware of the Sowter offering but that is a little expensive for my tastes. I am looking for something of reasonable quality that is not too expensive. good value for money.
Click to expand...

The Hammond 1650P would fit the bill. I used these for a pair of EL34 PP mono blocks, sounds pretty good to me.

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Talk to Phil Ramsey at Bluebell Audio. Bluebell Audio

Very helpful and knowledgeable chap.
 
#13
I can recommend this: Indel TGL40/001.

TGL 40/001 INDEL - Transformer: speaker | TME - Electronic components

tgl40_001.jpg



It is rated for 40 W but is huge and has 180 VA core. And don't care about the frequency response specified by the manufacturer.
With some 10...14 dB of GNFB this reaches beyond 100 kHz.
 
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#20
ruffrecords said:
Yes, just a single pair - 20W will be plenty. it will mainly be used in my workshop for music trials of my tube mixers. Don't really want to add a sterile sand based power amp at the end of the chain.

Thanks for the links.

Cheers

Ian
Click to expand...

I'm currently working on a st-70 clone el34 pp with a pair of James Audio's JS-6225HS model OPTs which I had them in hand. I must tell you that they are very good. Although they are marked as 20W with 90ma, I went over these ratings with no saturation at all!

Check them out, they are moderately priced but quite high quality transformers.

One more thing, in my amp I got very good results with 6p3s-e tubes replacing el34s too.
 
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