luvdunhill

a quick update. The toroids have arrived. The cases are in powder coating right now, and they expect to ship the middle of this week. I've contacted Digikey a few times and they are in the process of expediting the order from Panasonic for the P3884-ND parts. They will contact me today or tomorrow with a new ETA. I also sent everyone information for the remaining order at PartsConnexion, but they have not announced any discounts yet. Perhaps they will after their holiday (today). Thanks! -Marc

if such a thing really exists, it's absolutely stupid and would have all sorts of impedance issues for both the power amplifier and the electrostatic amplifier.

I think the term passive preamp is too generous... preamp outputs != preamp.

preamp for ESLs maybe

speakers != headphones

I'm waiting for Ray's amp to ship first... I want to make sure I can support a good lock onto his specific oscillation frequency. It will be the first electrostatic-to-electrostatic communications network... mil-spec of course... in fact, this message is classified and will self-destruct.

maybe that cap was being used as an RF antenna? KGSS with a built in FM tuner, sweet idea!

also, more capacitance is needed on the output of the supply and the effects of this on output impedance. It's an interesting trade-off, I agree, and one I'm wrestling with for my preamp.

the SB3 as a transport can be significantly upgraded if modded to directly tap the i2s output. I had the chance to A/B these configurations and it was quite impressive.

hm... I'll probably just use one of these: http://www.mouser.com/catalog/specsheets/MS-100656.pdf and the recommended switch for that part. Then just drill the panel with a simple through hole that will accommodate the above part. Then I can attach a PCB to the back of the panel and then adjust the height of the entire assembly via standoffs until things feel right.

so, the actuator is a similar stepped shape with a hole to accept the end of the tactile switch?

2N silver wire?

my heater beast of doom is nearing completion... swt61 got to catch a glimpse of it.

Pars: good point, but I think Neutrik plugs should have no problem fitting, as they designed the sockets as well well, still cannot decide on 1 or 2 box, so why not have both options? Seems nice and versatile. Final panel attached. Am I missing anything? On to the front... I would probably have the PCB be attached to the rear of the panel with some momentary tactile switches. Thus, I'd like to find / make some nice metal buttons, but not sure how to go about laying out the panel. Would I just drill out the back of a small cylinder and press fit it to the tactile switch, then have that poke out through the panel? Seems like a flange would be nice to hold the button in... what is the best way to go about this? Preamp-rear-final.txt

you dodged my post quite nicely over at Head-Fi in the DIY section. All of a sudden the KGSS is cheaper and easier?

so, FPE got back with me.. they can go all the way to 0.5mm, given the fact that the shapes used are circles, and the pattern I used now I just need to decide if there is a good reason to go single case over a separate case for the 2 r-cores and 2 PCBs. Now that I have my Tangent LNMP, perhaps I'll put it to good use and measure the difference(s).

That's the distance specified by Neutrik if using the PCB mount versions of the A, AA, B, BA series connectors. This will leave 1mm of material at the narrowest point. At some point I asked FPE and they said 2mm was the minimum they'd recommend, but they had instances of people going lower with shapes other than rectangles.

so, I'm working on a rear panel for a preamp. I'm going to use the high-density Neutrik XLR connectors and some nice compact RCA connectors. So, what do you think so far? (rename the .txt to .fpd to see the entire panel, not just the subsection that the .jpg is zoomed in on) I still need to add a umbilical cable connector (6 conductor) and a barrel jack and tidy things up a bit... Opinions? Preamp-Rear.txt

So, 47k will just be no loading resistor. I still recommend including a 100 ohm option. I'd recommend a quick read of this for everyone: Hagerman Technology LLC: Cartridge Loading Also, I forgot to include the RIAA resistors in the above BOM for PCx and it seems that PRP doesn't carry some of these values. Some are available in Holco though. Another option would be some Roederstein Resista from Percy, or perhaps he has the required values. I'm still investigating this. Main issue seems to be the 500R R19 value.

I'll have some-a-what he's having...

Pars: Thanks for the recommendation! All: So, I ordered the parts tonite. Total order was around $800. I had to add heat pads for the TO-220 devices to our order and I'll throw in the nuts, bolts, isolation shoulder washers and lock washers... I also decided to use something else for C4 and C6. Since some people are using larger capacitors, it would be nice to scale up the bypasses. Also, the speced capacitors don't fit very well, so I decided to use BC1626-ND for C4 and BC1631-ND for C6. I think MKT will be fine here. If anyone objects, I have some of the Panasonic P capacitors in various sizes and can put something together for you. After talking with customer service, they are going to hold the order until I tell them to release it. They say that P3884-ND should be in stock "any day". This is the only back order item. I also got the remaining 5 or so P3864-ND (1%) and added enough P3473-ND to match the remaining value for this spot in the RIAA circuit. Time to sit back and wait for PCx to announce their specials and wait for the parts to arrive at Digikey.

Hey, can anyone take this web page and generate a graphic for me: Fax ordering form, thlaudio Print screen and then pasting into a document isn't working so hot for me

a few things. First, the 35mm diameter caps are too big to allow proper airflow around the R2,R3 resistors that will be dissipating some heat. I'm going to have to change to 30mm caps for those with the upgraded kit and I'll keep the 35mm 22,000uF cap for the off board smoothing cap. Also, Digikey is out of 2 important parts, namely C12 and C13 for the RIAA circuit. Part numbers are P3864-ND and P3884-ND (Panasonic 1% polypro caps). I'm not sure where else you can even order these parts, but I'd like to keep the 1% tolerance if at all possible. I have everything added to a cart so we need to decide what to do about these important, missing parts. Looks like they are expecting them to be in stock around 08/28/2008...

Thanks Pete. I use around 150 ohms for my LOMC cartridge. A maximal set of values would be something like: 47, 100, 470, 1k, 10k and 47kΩ 0, 100, 270pF, 370pF and 470 pF Perhaps you can check around and see what other phono stages use? For the type, either mica, or the same Panasonic ECQP(Z) caps would be fine. What do you prefer? If you want some snubbers, I can do that. I usually use BC Mono-Kap and probably have a strip laying around somewhere I can include if that's okay with you.

this is really a taste issue. I find that bypassing the reasonably priced Mundorf M-Cap (or perhaps even better, the biggie box caps like Rifa PHE450 (yum) or Wima MKP4 / MKP10) with something nice is a reasonable option here, hence my default recommendation of the M-Cap with Russian teflon bypass. Depending on the Zin of your preamp / headamp, you can go with something lower than 10uF as well, so keep that in mind. I've also used Black Gate N (flame away for using a electrolytic as a coupling cap) with good results. The Auricaps are a good recommendation, as are Multicaps, or the Zen capacitors from North Creek's going-out-of-business sale. Outside of the above recommendations, I don't have much to offer