My 2nd engineer amp by Pete Millett. This time with Toroidy PT / OPTs and a Frontpanel module by John Broskie. I'm not very happy with my woodworking and might redo the case once I get my table saw. For those who don't know this fine design by Pete, see his original post.
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It's hard to judge from the pictures alone, but it looks like a very nice amp
Congrats!
Is the decorative front panel custom made? I'm trying to figure how to put front panel labels on my own amp...
Thx for the compliment. I ordered the front-panel aluminium plate from schaeffer-ag.de (like frontpanelexpress.com but in Germany). Not cheap but quality work. I attached the file. I regret the way I oriented the markings as the button screws are now on the side. I would look nicer with the 1-6 markings at top and the button screws at the bottom.
Such a machined front-panel is made out of anodized aluminium, that is later machined. Cheaper than machining then anodizing. The issue with it is that you have to embed the plate into the wood to hide the clear sides. I made a router template for this, significant work that I hope I can re-use at some point
Such a machined front-panel is made out of anodized aluminium, that is later machined. Cheaper than machining then anodizing. The issue with it is that you have to embed the plate into the wood to hide the clear sides. I made a router template for this, significant work that I hope I can re-use at some point
Hi everyone,
Just thought I'd share my first amp project, a tube headphone amp with integrated DAC.
The amplifier is based off a well-known OTL amp circuit which utilises 12AU7/ECC82 input & 6080 triodes and is output transformerless (OTL). It should pair nicely with the high input impedance of my my Sennheiser HD6xx headphones. Input options are either switchable line level analogue or USB digital. Digital input is provided via Khadas Tone Board. It currently has GEC CV 2984(6080) and GE 12AU7 tubes installed, these are just what we had easily available at the tim eof building and I had planned to upgrade them. After some research it seems the CV 2984 is fairly well regarded and an upgrade would be quite costly, but i'm interested in any recommendations.
This amp will predominantly reside on my desk at work, the decision was made to integrate a high quality DAC as I have found the sound output of modern office PCs to be quite poor.
I’m very happy with how it turned out. I've attached some pics below but there are more pics and full build documentation on my blog if anyone is interested. OTL Headphone Amplifier / DAC – Jeremy Young Design
Cheers,
Jeremy
Just thought I'd share my first amp project, a tube headphone amp with integrated DAC.
The amplifier is based off a well-known OTL amp circuit which utilises 12AU7/ECC82 input & 6080 triodes and is output transformerless (OTL). It should pair nicely with the high input impedance of my my Sennheiser HD6xx headphones. Input options are either switchable line level analogue or USB digital. Digital input is provided via Khadas Tone Board. It currently has GEC CV 2984(6080) and GE 12AU7 tubes installed, these are just what we had easily available at the tim eof building and I had planned to upgrade them. After some research it seems the CV 2984 is fairly well regarded and an upgrade would be quite costly, but i'm interested in any recommendations.
This amp will predominantly reside on my desk at work, the decision was made to integrate a high quality DAC as I have found the sound output of modern office PCs to be quite poor.
I’m very happy with how it turned out. I've attached some pics below but there are more pics and full build documentation on my blog if anyone is interested. OTL Headphone Amplifier / DAC – Jeremy Young Design
Cheers,
Jeremy
Hey I remember that one from your post on Reddit! Such an amazing build
Thanks! Yeah I'm kind of new to the DIY audio world so I've shared it in a few places, just trying to figure out the best place to share my builds and anything else I do in the future.
Love the wiring job you've done. I grabbed a copy of an image for future reference. Wiring is not my strong suit. In any case, very nice build. Any chance you could load the images directly to diyaudio? Several years later when the imgur images go away, others won't be able to see your great work.
going backwards?
This is kinda cheating because I have reworked an old amp, my first amp. But I had to.
In its original form it was too heavy to lift and carry down the stairs to the work shop for any required maintenance. I took the opportuniy to clean up my beginners work and to add DC regulated heat for the two tubes, a 12BH7A and the 45. I know DC heat on an IDHT is excessive but the whole amp is excessive! It was all about Low DCR and I nailed that! It is the most dynamic amp I have and the best I have heard. Everything you can do to assist a 45 I have done here. I am just too dang old to cart this amp with its Hammond Army around anymore and had to give in a four-part home. Anyway, I hope you like it. It is not as radical as it once was but old age will get you if you don't plan.
This is kinda cheating because I have reworked an old amp, my first amp. But I had to.
In its original form it was too heavy to lift and carry down the stairs to the work shop for any required maintenance. I took the opportuniy to clean up my beginners work and to add DC regulated heat for the two tubes, a 12BH7A and the 45. I know DC heat on an IDHT is excessive but the whole amp is excessive! It was all about Low DCR and I nailed that! It is the most dynamic amp I have and the best I have heard. Everything you can do to assist a 45 I have done here. I am just too dang old to cart this amp with its Hammond Army around anymore and had to give in a four-part home. Anyway, I hope you like it. It is not as radical as it once was but old age will get you if you don't plan.
Attachments
This is kinda cheating because I have reworked an old amp, my first amp. But I had to.
In its original form it was too heavy to lift and carry down the stairs to the work shop for any required maintenance. I took the opportuniy to clean up my beginners work and to add DC regulated heat for the two tubes, a 12BH7A and the 45. I know DC heat on an IDHT is excessive but the whole amp is excessive! It was all about Low DCR and I nailed that! It is the most dynamic amp I have and the best I have heard. Everything you can do to assist a 45 I have done here. I am just too dang old to cart this amp with its Hammond Army around anymore and had to give in a four-part home. Anyway, I hope you like it. It is not as radical as it once was but old age will get you if you don't plan.
Amazing!
Sounding of 6BQ6 is very, very close to 2A3. I listen now my SE 6BQ6 with big EDCOR transformers /instead 2A3/. I used China PCB for EL34 /27$ with parts/ and rebuilt for 6BQ6, that is a lot of times better. I advise You....Hurry, just the price is the same! /They read our forum..../.Swapped out the 6BQ6B for 6P31S. Wow. These tubes are impressive but wow they are a lot hotter since they are so small. Like a 6V6 with a plate cap dissipating 22 odd watts
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‘Tis 😎
Always over build if you wish to know where others have gone faint.
I have followed with interest those who might attempt a just-in-time/just enough for the job style which also makes sense. They were and are shooting in dark sometimes hitting upon just the right combination of elements with that single example/build. With this massive iron it’s just 10 ohms from the rectifiers to the tubes and less than 1 Henry total with strategy to the stationing of cap reserves, ripple is immeasurable, the sound is graceful and hugely dynamic. Overkill for sure but it’s always got what it needs in any fractional second. You just don’t want to drag this around to a friends house. It’s an installation 🤗
Always over build if you wish to know where others have gone faint.
I have followed with interest those who might attempt a just-in-time/just enough for the job style which also makes sense. They were and are shooting in dark sometimes hitting upon just the right combination of elements with that single example/build. With this massive iron it’s just 10 ohms from the rectifiers to the tubes and less than 1 Henry total with strategy to the stationing of cap reserves, ripple is immeasurable, the sound is graceful and hugely dynamic. Overkill for sure but it’s always got what it needs in any fractional second. You just don’t want to drag this around to a friends house. It’s an installation 🤗
My 2nd engineer amp by Pete Millett. This time with Toroidy PT / OPTs and a Frontpanel module by John Broskie. I'm not very happy with my woodworking and might redo the case once I get my table saw. For those who don't know this fine design by Pete, see his original post.
Absolutely a beauty congrats, I like the toroidal cover, how did you do that? Well I really don't see any flaws on the wood work I wish I could have your skill on the wood work, most of all how it sound? ....all the best and enjoy the music