More playing with depletion MOSFETs...
This time, I'm trying to get it to replace a 6SN7... So far, so good. A mu of about 20. 600V B+, 47k load, 350V at the drain.
This time, I'm trying to get it to replace a 6SN7... So far, so good. A mu of about 20. 600V B+, 47k load, 350V at the drain.
Tonight, we finally get to put the hacked Behringer to use with a despised old op amp that the supplier silently substituted for the other old op amp I ordered. I hacked one of them in two to look at the die - you learn some things just by doing that.
In case you're wondering: the op amp is merely in buffer mode. A lot more distortion than the Behringer itself.
And secondly, of course, H3 is higher although off-screen.
We're going to tame it, or break it, it doesn't matter in the least.
In case you're wondering: the op amp is merely in buffer mode. A lot more distortion than the Behringer itself.
And secondly, of course, H3 is higher although off-screen.
We're going to tame it, or break it, it doesn't matter in the least.
Attachments
I saw them a lot when researching some things, and of course, they were not very common. It seems they are even rarer now. I got some with my last order for which someone slapped me with unforeseen import fees but I'd rather use more common parts.
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Do you know of Atmos decoders people can buy or you have to write/build the decoder yourself?
I don’t know any atmos decoders. I’m just doing normal Dolby, which is 5.1. Im hoping to use the sta310 chip to do it. I’ve designed the board and have the chip, I just have to test it out in the next week or two.
Nice project. I have an old Panasonic SA-HE100 that has one channel broken. I thought of getting the digital boards just for the decoded output and do some experiments with it. Similarly, not Atmos though but the usual 5.1 Dolby and some other things like DTS and DTS-Neo.
I suppose for Atmos they license it to manufacturers. It would also be interesting to find details about the up-firing speakers and how to build them. They look like simple affairs.
I suppose for Atmos they license it to manufacturers. It would also be interesting to find details about the up-firing speakers and how to build them. They look like simple affairs.
I'm a tube guy so depletion mode makes sense to me
IXTP08N100D2 is the part I'm playing with.
LU1014D works great as power JFET. With a cascode it can really have a lot of muscle. I was running 3 to 5 amps through them on the LuFo amp. Hard to imagine a tiny thing like this can handle it.
https://www.diyaudio.com/community/threads/assembling-the-lu1014d-ims-to-247-adapter.373273/
These have nice SIT behavior from the curve traces that Woofertester took.
https://www.diyaudio.com/community/threads/assembling-the-lu1014d-ims-to-247-adapter.373273/
These have nice SIT behavior from the curve traces that Woofertester took.
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Is that an aluminum PCB to act as a heatsink? Looks neat.
I just finished up my Krell KSA5 (Kevin Gilmore clone) following the alexcp mods over at https://www.diyaudio.com/community/threads/krell-ksa5.109618/post-6483037 AMB Sigma 22 set to +/-21vdc, a loop breaker, and under the trafo shield is a Triad VPM48-1040. I still need to do some front LEDs, and swap the ground bolt to a brass one that's coming tomorrow, but I wanted to get this thing on my desk asap. Biased at about 18mA. I used a switched headphone jack to cut the RCA outs so as to not bother people with my music when using voice chat, sick of my RCA splitter for my powered sub, I did 2 sets of outputs, one for my LM1875 amp and one for my sub.
I don't have a lot of headphone amp experience to compare it to, just a Schiit Magni 3, Schiit Vali 2+, and an AudioEngine D3, but wow this amp sounds fantastic, clean as a whistle, loads of power, lots of nice low end. Running it right now on my Hifiman x Massdrop HE-4XX's, tested it earlier on my Sony MDR-7506's. I don't use headphones much, really only when I game, and I expect to use this more as a preamp, but this amp might change that.
The desk is filthy, and I now need to wall mount my Overnight Sensations as this is 430mm wide. Not a big deal, it's incentive to do a little cleaning.
Next up will be finishing my FH9HVX.
I just finished up my Krell KSA5 (Kevin Gilmore clone) following the alexcp mods over at https://www.diyaudio.com/community/threads/krell-ksa5.109618/post-6483037 AMB Sigma 22 set to +/-21vdc, a loop breaker, and under the trafo shield is a Triad VPM48-1040. I still need to do some front LEDs, and swap the ground bolt to a brass one that's coming tomorrow, but I wanted to get this thing on my desk asap. Biased at about 18mA. I used a switched headphone jack to cut the RCA outs so as to not bother people with my music when using voice chat, sick of my RCA splitter for my powered sub, I did 2 sets of outputs, one for my LM1875 amp and one for my sub.
I don't have a lot of headphone amp experience to compare it to, just a Schiit Magni 3, Schiit Vali 2+, and an AudioEngine D3, but wow this amp sounds fantastic, clean as a whistle, loads of power, lots of nice low end. Running it right now on my Hifiman x Massdrop HE-4XX's, tested it earlier on my Sony MDR-7506's. I don't use headphones much, really only when I game, and I expect to use this more as a preamp, but this amp might change that.
The desk is filthy, and I now need to wall mount my Overnight Sensations as this is 430mm wide. Not a big deal, it's incentive to do a little cleaning.
Next up will be finishing my FH9HVX.
Tonight I rigged up a mono modular amp on the bench to run some tests...
I found out that a pair of push pull 6P31S tubes connected as triodes can make 37.5WRMS! Am I ignoring the datasheet? Yup! But wow!
OP = 320V B+, 35mA, 2k2 load.
2W bias pots and they still get warm, too.
I found out that a pair of push pull 6P31S tubes connected as triodes can make 37.5WRMS! Am I ignoring the datasheet? Yup! But wow!
OP = 320V B+, 35mA, 2k2 load.
2W bias pots and they still get warm, too.
Hi Bloqhead,
Yes, that’s an aluminum integrated metal substrate (IMS) PCB that acts as a heat spreader and permits the pesky little JFET to be mounted and used like a standard TO-247 but with extra clamp bolt holes all around.
Beautiful work on the KSA-5 clone headphone amp. That chassis reminds me of a Pass HP-1.
If you are looking for a great next headphone amp project, check out this one that I have. It has lots of power to drive power hungry HiFi man planars and is SE Class A DC coupled. Original topology by TimS.
https://www.diyaudio.com/community/...-coupled-class-a-hpa-with-sub-ppm-thd.323594/
Each channel is very simple:
This is Avtech23’s build with the integrated stereo version with custom low noise PSU:
Here is my build and measurement:
Yes, that’s an aluminum integrated metal substrate (IMS) PCB that acts as a heat spreader and permits the pesky little JFET to be mounted and used like a standard TO-247 but with extra clamp bolt holes all around.
Beautiful work on the KSA-5 clone headphone amp. That chassis reminds me of a Pass HP-1.
If you are looking for a great next headphone amp project, check out this one that I have. It has lots of power to drive power hungry HiFi man planars and is SE Class A DC coupled. Original topology by TimS.
https://www.diyaudio.com/community/...-coupled-class-a-hpa-with-sub-ppm-thd.323594/
Each channel is very simple:
This is Avtech23’s build with the integrated stereo version with custom low noise PSU:
Here is my build and measurement:
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Thanks X, that little head amp is now on my list after a few speaker amp projects are cranked out.
I think the chassis is a Pass HP-1 inspired chassis, you know how it can be poking around on aliexpress for a nice chassis.. half of the ones that are eye catching have "Pass" in the name 😀 Originally I wanted to inlay the headphone jack like the HP-1, but with my board layout, it wouldn't have fit, or would have been too tight for my tastes.
I think the chassis is a Pass HP-1 inspired chassis, you know how it can be poking around on aliexpress for a nice chassis.. half of the ones that are eye catching have "Pass" in the name 😀 Originally I wanted to inlay the headphone jack like the HP-1, but with my board layout, it wouldn't have fit, or would have been too tight for my tastes.
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Hope you stocked up on them because last I checked there was a single one at Digikey and the waiting time was 64 weeks or something.
There are a couple of IXCPs in my SET Tube Amp too...
...but working with unobtainium for DIY experiments is no fun to me.
I have 8 left... I'm not planning on blowing up anymore of them lol
Testing a concept for a powerful Class AB headphone amp driven by a SE Class A MOSFET follower buffer stage. Here I am using a COTS TPA6120A2 headphone amp driven by my JFET/MOSFET Desktop Class A topology to give it a nice dominant second harmonic distortion profile.
Very nice sounding amp and a good proof of concept.
Very nice sounding amp and a good proof of concept.
Something really beautiful on the bench tonight. The pre-production chassis for the Bob Carver RAM285 just arrived. 7.6kg of custom CNC’d aluminum, beautifully bead blasted and anodized to a satin smooth velvety finish. This has got to be one of the best looking amp chassis I have ever seen or held. The fit and finish is immaculate. The scale has to be seen to be appreciated. A huge thanks to Darko M., for the mechanical engineering and 3D CAD work that made this possible.
