Hey Everyone,
So, I decided just to stick with OSHPark.
If there is enough interest to do 10 boards the cost is $31.50 a set. This includes the main phono board, the filter board and the 8dip adapters (these are so cheap, why not?)
I was thinking of using the “After Dark” option which gives us black boards with clear resist. So, they won’t even have to be purple.
Any takers?
Regards,
John
So, I decided just to stick with OSHPark.
If there is enough interest to do 10 boards the cost is $31.50 a set. This includes the main phono board, the filter board and the 8dip adapters (these are so cheap, why not?)
I was thinking of using the “After Dark” option which gives us black boards with clear resist. So, they won’t even have to be purple.
Any takers?
Regards,
John
An AK poster is getting together a buy of phono and HP boards if anyone is interested.
Incidentally the SOTA commercial versions of the phono stage (the Pyxi and the Acrux) were just very successfully (or so I'm told) shown at CAF and there will, seemingly, be reviews forthcoming in the audio press.
I have no commercial interest in any of this.
Incidentally the SOTA commercial versions of the phono stage (the Pyxi and the Acrux) were just very successfully (or so I'm told) shown at CAF and there will, seemingly, be reviews forthcoming in the audio press.
I have no commercial interest in any of this.
@6L6 dropped this phono project on me because he probably knows I'll build it immediately. V3.2 boards are ordered (file says 3.2, gerbers say 3.1—they are not in hand yet). There will be 6 available (need 2 if you want to build MM plus MC)—actual PCB cost + shipping + envelopes + first come first serve — up for grabs with a PM...
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The somewhat simplified/inferior spec version using SM devices and switchable input loads is available commercially, but I have no financial interest in it. There have been several extremely complimentary "professional" hi-fi reviews, and a rather poorly executed measurement-based review by ASR. The architecture is pretty well universally "loved", even by those who normally like tube designs.
It's probably not a coincidence that interest in the DIY design has suddenly reappeared.
It's probably not a coincidence that interest in the DIY design has suddenly reappeared.
Wyn, I do get the impression that you are over and done with any kind of DIY forum support (totally okay IMO, no complaints)—BUT—
—I came across a little confusion (for me) with implementing the balance control on pot and stereo/mono on a switch you added in v3 when building 2x boards for MM and MC—I didn't see my question covered in any of the docs or threads—or I missed it. My instinct tells me I need to populate the balance and stereo/mono parts on BOTH boards? And then perhaps join leads from each board at the pot in the case of balance control or switch as detailed in v3 addendum for stereo/mono....I'm basically building for all options, except Mute and Volume (one of the things that makes your design so cool), but only as a phono pre in my case, no source switching, no headphones.
Thanks!
—I came across a little confusion (for me) with implementing the balance control on pot and stereo/mono on a switch you added in v3 when building 2x boards for MM and MC—I didn't see my question covered in any of the docs or threads—or I missed it. My instinct tells me I need to populate the balance and stereo/mono parts on BOTH boards? And then perhaps join leads from each board at the pot in the case of balance control or switch as detailed in v3 addendum for stereo/mono....I'm basically building for all options, except Mute and Volume (one of the things that makes your design so cool), but only as a phono pre in my case, no source switching, no headphones.Thanks!
No, only one line section including balance/mono needs to be populated. This function occurs after the RIAA stage selection is made.
Yes, I am stepping back from "support" of the DIY stages. I'm doing a fair bit of "support" for Sota and that's enough to use up the spare time I have to allocate to this area.
Yes, I am stepping back from "support" of the DIY stages. I'm doing a fair bit of "support" for Sota and that's enough to use up the spare time I have to allocate to this area.
Cross posting with the "official" build thread here. Works great, first try! You can read my full comments on the other thread—I'll finish up the lid and sort out some bizarre LED blowing issues—I think I might have a bad batch—not sure if that is a thing or not—first time using 3mm LEDs. I'm just gently poking them into a 3.4mm hole in the aluminum and they seem to object to that....
Thanks Wyn!
Thanks Wyn!
Very cool. I just got boards and parts for Rev 1 (yes Rev 1) But I can wait for the new rev before building, When will the necessary gerbers and docs be ready?
Many thanks!
I’m glad to read the v4.0 will transition to fruition.
Each version of this phono stage has been regarded as excellent, and the level of attention put into confirming the design operated perfectly was a big part of what attracted my interest.
My order of v3.2 arrived in Canada, yesterday. I appreciate the tight layout still permits removal of socketed DIP-8 devices using IC removal tools.
Thank you Wyn, Hypnotoad, GKTAUDIO and everyone. I can’t wait to get one assembled and hear the circuit in action.
Each version of this phono stage has been regarded as excellent, and the level of attention put into confirming the design operated perfectly was a big part of what attracted my interest.
My order of v3.2 arrived in Canada, yesterday. I appreciate the tight layout still permits removal of socketed DIP-8 devices using IC removal tools.
Thank you Wyn, Hypnotoad, GKTAUDIO and everyone. I can’t wait to get one assembled and hear the circuit in action.
Well, there are some steps to go. The new stage can be configured as a fixed buffer or as the 75us input stage. As a buffer it can be used to precede a MM stage of the prior architecture, to enable a switched MC/MM design. As a 75us stage it can replace the dual opamp configuration. The difference is a resistor or two and a capacitor.
We plan to build a prototype buffer and configure it both ways, then see how it does in the two applications. There is some optimization required- noise vs distortion and opamp selections. Currently a NE5532 seems adequate, but an OPA1656 may in fact be better overall and as they are currently in use it may be a better option.
The warp filter is up and running, and works as expected.