[LobalWarming]

Can you direct me to any good information on building external output transformer houses? I'm learning electronics as I go, mostly simple repair jobs and it's something I think I'd want to take a stab at as a project.

Here's where I got started - his traffo-housing is more modern and neater than mine:
https://www.head-fi.org/threads/output-coupling-cap-and-transformer-mod.652270/post-9211384

I didn't bother with a switch, because I got a great deal on Amphenol 1/4" stereo jacks. 4 for input (1k, 500, 375, 250 ohms) and 2 for output, 4 and 8 ohms.

Here's the finished traffo-house in a $6.00 Michaels box.

I'd show the insides, perhaps on a PM. There are people here who are spaghetti-wiring sensitive.

 

[muchacho]

So the Christmas gift for me manifested itself in the form of a headphone amplifier and I am a new user of Wieslaw's work and that is the H5 KPCU, which was created exactly according to my ideas... I am delighted with the sound and my HD660S2 sounded better than with the TA-26. Just a small question, when switching off the H5 emits a not very strong pop into the headphones, which I did not know from the TA-26. Is this the case for all H5 users? I don't think it's strong enough to hurt the headphones and I don't want to unplug the headphones every time I turn off the amp.

 

[roderickvd]

So the Christmas gift for me manifested itself in the form of a headphone amplifier and I am a new user of Wieslaw's work and that is the H5 KPCU, which was created exactly according to my ideas... I am delighted with the sound and my HD660S2 sounded better than with the TA-26.

Congratulations! What does the lever switch do? And the LED bulb - was that by your request or something Wieslaw put in himself? (so far I've seen LEDs that were level with the cover -- no bulb protruding)

Just a small question, when switching off the H5 emits a not very strong pop into the headphones, which I did not know from the TA-26. Is this the case for all H5 users? I don't think it's strong enough to hurt the headphones and I don't want to unplug the headphones every time I turn off the amp.

A pop? Yes. But "very strong"? No not on either my H5 or H7, paired with high-Z Beyer cans with Tesla drivers.

 

[Joshjns]

So the Christmas gift for me manifested itself in the form of a headphone amplifier and I am a new user of Wieslaw's work and that is the H5 KPCU, which was created exactly according to my ideas... I am delighted with the sound and my HD660S2 sounded better than with the TA-26. Just a small question, when switching off the H5 emits a not very strong pop into the headphones, which I did not know from the TA-26. Is this the case for all H5 users? I don't think it's strong enough to hurt the headphones and I don't want to unplug the headphones every time I turn off the amp.

Congrats, I also have the H5 KPCU.. but my transformer is hidden, pretty much everything is in a different position actually !

 

[muchacho]

I had the amplifier made by Wieslaw according to my ideas and he made the amplifier perfectly as I wanted. My requirements were: a transformer admitted outside (I'm "old school" and the transformer simply belongs to the tubes + better cooling of the transformer), headphone output connector from the front (so that the cable at the headphone connector does not get twisted by a sharp bend at the top), NEUTRIK with locking, orange LED indicator light (to match the color of the glow tubes) and a sensitivity switch (GAIN). I would not use the output RCA connectors, so they are not used. By the way, Wieslaw wrote me that my amplifier is probably the last one with a transformer outside, now probably only inside. As for the popping, I also think it's not strong and won't hurt the headphones. I am satisfied with the amplifier in all aspects, both the quality of the production according to my ideas, but mainly the quality of the sound...

 

[roderickvd]

I like the front outputs. Never really understood why they had to be on top except for reasons of tradition…

Cool idea about the gain switch. What can you switch it to?

Happy new year everyone!

 

[kid vic]

Hi,
Has anyone, ever, tried a Denon AH-D7200 (25 Ohm) on a Eufonika (OTL) tube amp?
Probably not the best of choices/pairing...

All input appreciated.
Thank you and Merry Christmas

I use the near cousin of that headphone (Fostex TH600) off and on with my Eufonika H4 and its not bad. You will not get the best bass with a combo like that and you will lose a little air but overall it is a pleasant listen

 

[muchacho]

I like the front outputs. Never really understood why they had to be on top except for reasons of tradition…

Cool idea about the gain switch. What can you switch it to?

Happy new year everyone!

I also wish everyone a happy new yEAR! (this is what Wieslaw wishes...!)
I didn't like the upward headphone output and it seemed prone to damage to the cable at the connector. The idea with the input sensitivity switch occurred to me already with the TA-26. Because I have a DAC with a fixed output line level of 2V (similar to most CD players) and I turned the volume control to a maximum of 9-10. hour, (exceptionally the 11th hour) when the volume level was already quite high. This way I can lower it and the volume control is not so sensitive. One more thing, Wieslaw is a funny guy because he came up with the suggestion when I designed the amp to also finish it and tighten the screws that hold the transformer on the bottom (see photo)...!

 

[oldson]

As a woodworker, if a piece I made was damaged like that in the shop, I'd put a roundover on the whole top edge and call it a day. If you taped it off we'll, you wouldn't even need to disassemble it.

how easy is this to do?
i have given up all hope of ever receiving a replacement case.

 

[1siedem]

Hi
Did You compare H5 and H22?
What are the differences?

 

[andrewchoppa]

Hi people,

Just received my final iteration of Wieslaws's prototype OTC amp. Red one is original which he asked me to give feedback on and he would build the final amp based on info. The first amp sounded great but had a hum (maybe transformer related?) Tan one is new. New one doesn't have heat-sinks on side. New one doesn't have a hum. New one sounds MAGNIFICENT (old one sounded pretty bloody good too!). Honestly, could not be happier. This thing SLAMS with my Hifiman HEK Stealths. I have upgraded (I assume) to a pair of 6sn7 Tungsol GTBs - and am enjoying them. What other 6sn7 tubes should I have in this amp? TIA

 

[LobalWarming]

Hi people,

Just received my final iteration of Wieslaws's prototype OTC amp. Red one is original which he asked me to give feedback on and he would build the final amp based on info. The first amp sounded great but had a hum (maybe transformer related?) Tan one is new. New one doesn't have heat-sinks on side. New one doesn't have a hum. New one sounds MAGNIFICENT (old one sounded pretty bloody good too!). Honestly, could not be happier. This thing SLAMS with my Hifiman HEK Stealths. I have upgraded (I assume) to a pair of 6sn7 Tungsol GTBs - and am enjoying them. What other 6sn7 tubes should I have in this amp? TIA

Looks great!

What other 6SN7s... What's the budget? Unlimited. Great! We can help.

You can spend a few months touring the NOS tube factories in the States (as well as spending lots of USD). Check the 6SN7 ID thread. Then the 6SN7 Reference thread to be fully ref'd up.

If this was 2010, then you would need to track down a pair of Tung-Sol Round Plate 6SN7s. Probably cheaper to time travel, than purchase now. Classic rich tonality. Everyone should have a pair. Or two. Even better, some say, is the TS VT-99 round plate - the round plate predecessor to their 6SN7. Need adapters, but let's try to stay on the 6SN7 track - try to stop interrupting.

Over on the Sylvania ranch, a pair of VT-231s. Classic Sylvi sound - a bit brilliant up top - and clean on down. Or consider a pair of the Sylvi 6SN7Ws instead - great resolution and tight bottom end. But probably best to get both. Again if you had adapters, the Frankie loctal 7N7 has the same innards as the 6SN7W for lower cost... but more adapters and I asked you not to mention those. Yet.

There's also the Gold Brand Sylvania 6SN7GTB that has move up my rankings. Tough to find a pair tho.

CBS/Hytron 6SN7GT is a more mellow alternative to the showy Sylvi's. Very sweet tone for a sweet price.

Now let's take a seaplane over to the old country for a pair of Brimar 6SN7 (CV1988) - delightful midrange and one of my fav 6SN7s overall. The linked pair is the clear glass which I enjoy - and that pair isfrom a Kiwi seller which is just a couple derogatory remarks away from your land.

The black glass Brimar 6SN7 are very special as well - especially the price.

There's only a few dozens more to suggest... but will save something for later. Yes, including your keen apatite for adapters.

 

[OctavianH]

If it uses 2 x 6SN7 I expect internal triodes are in parallel? The first question I would ask Wieslaw is if 6N7 work via adapters.

 

[LobalWarming]

If it uses 2 x 6SN7 I expect internal triodes are in parallel? The first question I would ask Wieslaw is if 6N7 work via adapters.

Please see above... we're not talking about adapters yet... @andrewchoppa wants to spend hundreds thousands on 6SN7s first.

And yes, it will work. But so will a pair of ECC40s from 1952 or a quad of delicious L63s... but we're not there yet.

 

[OctavianH]

Please see above... we're not talking about adapters yet... @andrewchoppa wants to spend hundreds thousands on 6SN7s first.

And yes, it will work. But so will a pair of ECC40s from 1952 or a quad of delicious L63s... but we're not there yet.

Well, 6F8G and 7N7 are equivalents, so you can forget about the adapters and just imagine they are invisible

I feel sad about your wallets.

BTW, mr. Choppa would be cool to compare the Eufonika with his McChanson and let us know what's different and how.