Pars

I guess I would like something just for audio testing (view on scope). Something that can do sine and square waves, sweep would also be useful. My thoughts revolve around testing stuff like the DynaFET for oscillation by running various frequencies thru it. Testing above 20kHz might be useful as well; don't think I can do that with the PC setup right now but hit sure. Sent from my iPhone using Tapatalk

Any recommendations for one, used and cheap preferably? (I know, non-HC). I was looking at a couple of B&K 4011s or maybe an HP3311a? Other? Or am I better off using a PC with my mAudio box and a program (can't remember which one I have, but it isn't bad).

Yep, RIP. Great in a lot of roles. Tombstone was another one. I also recall some movie where he was a B52 pilot in a nuclear war, didn't drop his bombs and just flying around waiting for fuel to run out at the end (world destroyed). Dawn's Early Light or something like that? Sent from my iPhone using Tapatalk

Oh... Never mind... bitch! See SNL, Emily Litella Sent from my iPhone using Tapatalk

Just a caution regarding these supplies and a variac... Until there is sufficient input voltage for the opamps to start up, they will behave strangely and all the LEDs will not come up. And to echo mwl1968's comment, it is very poor practice to not test the PSUs first before connecting the amp board(s) if possible. Sent from my iPhone using Tapatalk

Happy Birthday! Sent from my iPhone using Tapatalk

Wow Reks! Take care of yourself, scary!

Cool! Man, you're like the energizer bunny with all these projects going on! Where do you find the time?

Happy Birthday! Sent from my iPhone using Tapatalk

Happy Birthday Ari!

Looks like it could be this thing. 2 PS boxes http://www.hifido.co.jp/KW/G0402/E/0-50/C15-88544-54496-00/

Happy Birthday! Sent from my iPhone using Tapatalk

That thing is awesome Kerry!

You didn't wire the primaries in parallel for 120V? I guess I've never heard of that being done (not that that means anything).

Went over to the HF thread and someone is still maintaining this is SOTA, yada yada... Took a look at the company, and... Italian. Hmmm, Rudi? Looked back on HF and I see our old friend Nik had messed about with an Angstrom preamp back in the day (didn't read the thread(s)). Good times

Hmmm... interested in the Aeons. Impressions of these from someone not on head-fi would be of interest.

Got my package the other day, thanks Steve! Boards look great, though a bit larger than I had anticipated (SMT). Now for some Molex KK connectors

It seems that most who want a tube output DAC are not looking for the most linear stage they can get, but instead are looking for the "tube sound" in an attempt to quell the digital nasties Kevin: I guess I hadn't looked closely at soekeris (sp?) and other more recent r2r DACS to note that they are V out. Older r2r DAC chips (TDA1541A, PCM63, etc. were usually I out. The 1541 seems to be a frequent target for lampizator, etc. Sent from my iPhone using Tapatalk

Someone with more knowledge than I please correct me, but for a current-out DAC, tubes aren't a good choice for an I/V converter as these expect very low input impedance (0 ohms, i.e. dead short preferably). Most of the tube stages you see are resistor I/V with the tube stage just being a buffer and maybe some gain. The SRPP tube stages that are bandied about are a very poor choice, but Doug or Kevin could give better advice. Sent from my iPhone using Tapatalk

^ And that won't work for thick panels. Not sure if a good hole saw would work?

Wow... $13K gets you mostly stripboard? That thing looks like its set for mass production and would be a nightmare to work on/troubleshoot

I checked it last night and a 6-32 fits perfectly, no drilling involved. Sent from my iPhone using Tapatalk

Thanks. Right after posting and going thru mouser, I had run across the 4180g which sounded quite familiar from all my reading of the electrostat amp threads. Duh Are any insulating washers required or recommended for TO-247? Looks like a 6-32 screw fits quite well. Sent from my iPhone using Tapatalk

Just built and fired up a +/-30V GRLV for this. In conjunction, I never had checked the power draw of the amp boards. My spice simulation showed 366mA. Actual was 415mA or so at initial startup, dropping to around 375mA when kind of warmed up. This is at bias of 150mA and 2 pairs of outputs. Tested using the sigma22 I already had in here. I had thought that I might see a higher draw than the model due to the buffers/Vbe mult. running warmish, but the actual was fairly close to the model.

Just tossed together a GRLV for my DynaFET and fired it up. Works fine (so far). +30.005/-30.014 Vdc on my HP. I finally got around to measuring current draw on the DynaFET boards; around 415mA on startup, drops to ~375mA when warmed up mostly. This is at 2x pairs outputs biased at ~150mA each. Pretty close to my spice model (366mA). So the GRLV will be seeing around 750mA total. I just realized that the MJW pass transistors have an exposed back (sitting at around 50V on these), so I am going to need some pads or insulators when I mount these to the heatsink (common). What do you guys like for thermal pads for these? Didn't see any in the BOM I have. Also, is there a fully insulated version of the pass transistors? Might switch to those, but from what I read, the MJW is supposed to be the insulated version?