Do It Yourself

Got a couple pictures last night at last. It's been running for a few weeks now, I kept tinkering with it, but it's pretty much done for now. Built mostly from parts on hand, plus an old scsi drive chassis. I did buy a few resistors once I had settled on working values, if only to replace a couple series and parallel conglomerations. Obligatory off and on shots... Started with this lumber and chassis... [ATTACH=CONFIG]3086[/ATTACH] [ATTACH=CONFIG]3087[/ATTACH] There is another thread (dead bug psu) that shows some other pics along the way. The amp is derivation of the mapletree design; it has higher operating voltage, similar to his super, though t…

Hello all, I'm working on a little project with my old SRD-6 energizer and a cheapo TA2020 amp. I'm trying to put together a compact transportable setup for my SR-5s. I have done a few modifications to this box already, such as wiring the transformers directly to the speaker taps on the back of the box and directly to the Stax socket on the front, completely bypassing the bias board and the loudspeaker switch. Those mods have done great things in terms of sound quality, but what I'm interested in now is modifying the bias circuit to operate as a self biasing one. As I understand it, Stax accomplishes this by tapping some of the output signal from one of the transformers, …

I was adding a switch to my brother's NewClassD amp, but am having a curious situation. The switch was to go between SE->bal (4PDT), wired up basically like what Kerry did with the relays on the mini ss DYnalo: Everything ohms out correctly, but when I went to test it, the R channel works perfectly (in either position), but no sound from the L channel. I took it all apart tonight (not the switch and input wiring), but disconnected from the amp boards, etc. Everything once again ohms out perfectly, no shorts. L- and R- shorted to gnd when switch is in SE position, straight thru then not. The XLRs are the metal Neutriks like the NC3MD-LX-HE, etc. The only …

So I'm turning one of my garage bays into a workshop. I'm able to fit 8' x 10' with a 9' 6" ceiling no problem. I need some ideas on counter surfaces and cabinets. I'd need some storage, an area for a desktop and 4-6 amps, 2 dacs, and a preamp. Lastly an area to work on projects. Is there an online layout tool that doesn't have a huge learning curve or anyone on here that can do a layout? I'd gladly throw a few bucks their way for some time.

I'm considering getting a few Pass Pearl phono PCBs made up. Is there any interest here?

The mains cable (crappy 2-wire zip cord) on my SRD-Pro is a bit old and warn, and seems way too long. I would like to replace it with something that's of better quality. Of all the better (google results) power cable I've seen, it's all three wire, some shielded and some not. One article on Belden's three-wire shielded (#83803) mention constructing so that at the plug end, the shield wrap and the the ground wire are connected to the wall plug. At the component end, leave the shield floating; use the shield to capture interference traveling through the cable (in or out) and to ground them to earth so they do not cause any unwanted noise. My question is, if I choose a…

Nobel Prize on physics caught my attention this year. I've been reading about graphene and its peculiar proprieties. According to Yu

That's right. A few upgrades and tweaks for the old gal. On the list will be opamps, wiring reroutes and upgrades, power supply changes. First up, I'm going to remove these JRC4735B opamps (assuming I have correctly identified them) and replace them with...dunno. After reading up a bit it appears that these are part of the problem with this player sounding so dark. I'll have to do some comparisons, but it seems like an OPA2134 could be a candidate, or an AD8610 (or 20). Guesses? I'll have to check the pinouts to be sure.

Posted this on the other forum, but I get the feeling the audience here will probably enjoy this as well. If I'm breaking any rules by posting this here too please let me know....or just delete it. Cheers. I've started building a pair of Zaph's Bargain Mini's (ZBM) along with Zaph's SR-71. I'll be documenting my build progress in this thread with pictures and comments. Making this thread somewhat for your entertainment and for me to use it somewhat as a log of progress (or lack thereof) as these will basically be my second and third woodworking projects to date. Hope you enjoy this thread as much as I (hopefully) will enjoy the build! I'm planning on building the bo…

I'd like to call into question some do's and don't I've heard about building Stax amps. I'm an engineer who works on scientific instrumentation and have heard a few things I don't understand based on my experience, so thought it's worth a discussion here. Please correct me if my thoughts on these issues is incorrect, from an engineering perspective. High Voltage resistors are necessary In general HV boutique resistors are really only needed when there’s a large differential voltage. Let's take a high quality but not HV resistor, the KOA Speer which range from 250V-1kV working voltage http://www.koaspeer.com/catimages/Products/MF-MFS-RK/MF-MFS-RK.pdf Take…

Hi STAX guys, first of all greetings from Munich, Germany. Within the last weeks i read a lot in your huge STAX Threads and learned a lot about the moddings that can be done throughout the hole STAX product line. But to be honest I lost control about the information I got. That is the reason why I opened a new thread. I own a STAX SRM-1 MK2 (early A-Serie) (my father bought it in 1983 when I was born 😊 ) and it has the very early number A5327. In the PDF you can see the wiring diagram which is for units beginning with number A5494 (so different from mine). The unit was not in use within the last 20 years and I already replaced the electrolytic caps (Nichicon LKX…

Does anyone happen to know a good place to get the parts to build one? Wanted to make one for my iPod Touch Thanks!

I was impressed to see the great work done on these two sets of Stax Lambda Pro drives by Jazz over at Head Fi that I thought that his post should be duplicated here for members to see. Don't know how many times I played with my Lambda phones on my head to see if I could simulate Sigma style sound. Kudos to Jazz for two jobs well done. See JaZZ's custom made Stax Phones here...Homemade Headphones? - Head-Fi: Covering Headphones, Earphones and Portable Audio Jazz's comments below..... The idea of making my own housings for Stax drivers was born out of my experience with the Lambda and the Sigma Pro. Whereas the Lambda sounded too shrill (with the SRM-1 [?]) -- and …

Hi Gents, I

I purchased this DAC from another HC'er in Canada down to the states but it looks like maybe he didn't get around to testing it out before selling it to me as it locks onto digital signals but provides no useful output otherwise. I only have a glimpse of the history of this thing but it's lived a rough life. I am positive old forum favorite NoNoNoNoNoNo is the previous previous owner and the work here is very very bad. Lots of WTF and cold solder joints everywhere and bonus scorch marks on some box caps, that odd white wire is a jumper used after he lifted a pcb trace... As a novice I have since cleaned this thing up as far as I can get it, at least at my skil…

So this is the time of the year from thanksgiving to new years where i have the time to do extraordinary projects. This year is no exception. So i delivered the hydrogen torch preamp prototype to a person in chicago that happens to own a ctc blowtorch with great success. (hearafter just refered to as just hydrogen)(a hydrogen torch is at least twice the temperature of a blowtorch) But this year i wanted to do something extremely over the top just for me. And while it is not done yet, enough of it is done for a couple of pictures. So I hereby present the $5000 hammer. (in fact its going to cost way more than that) http://gilmore.chem.northwestern.edu/hammer1…

Some of you will remember my first turning on my new lathe that Vicki affectionately dubbed the Peppermill. Well the Peppermill has been repurposed, or should I say purposed. It's now part of a headphone stand for a Head-Fier that wanted a 4 phone stand. It's not finished yet, it still needs a few more coats of lacquer. I thought I'd post it though because it's rather unique looking.

I'm looking for suggestions of interesting DAC designs and/or PCBs/kits. I guess I'm shooting for the higher end of things, and PCM1704-based stuff has gotten my attention. So far I've found the Hagerman Chime and TentLabs kit. Any opinions on these? Anything else I should consider? Also, are there any standalone USB-I2S or analog output stage kits worth looking at? Thanks!

So I've been on vacation for the last few days and decided to go play with my tube amp since I had nothing better to do. After reading a whole bunch of stuff on the diyaudio forums I got a bunch of stuff together and played around with various power supplies for the heaters in my tubes. First off was a generic DC power supply I got as a kit in the local electronics store way back when. It sounds decent, with Grados there's more background hiss than I'd like but other than that I didn't notice anything wrong with it until I got the good stuff. Next was a benchtop power supply I found in the surplus shop. This is the quietest power supply, with Grados there's just the…

I was chatting to justin and cetoole last night, asking for a solution to produce low volumes of sound, max -40dB down into the -80`s and below. Comfortably loud for me with my rs-1`s is up to -52dBu with pro mastered (+4dBu) material, using my donuts (yh-100`s) comfortably loud rises up to -44 dBu. The suggestion that came up, apart from a vinyl source was to I know very little about what is required to drive electrostatics so will really need a builder to construct this for me. A pre-built stuffed Stax bias supply PCB is available from spritzer. I`d really like to try this with my SR-3`s. Anyone willing to construct this for me please let me know. I ha…

Not sure which forum is the most appropriate place to post this topic. since it's technical in nature I chose this DIY forum. My question is - which Stax amps can one safely use the KT77 in place of the EL34 output tubes and why. Judging by the KT77 spec as stated on the datasheet, it should be compatible to the EL34 in terms of plate voltage and dissipation, etc.. But it has been stated by many that the KT77 should not be used in the BHSE. Can someone explain the technical reasons behind it? Also, what about using the KT77 in the Grounded Grid, Megatron and the DIY T2 and why. For me, it's both a learning exercise as well as a practical question - I've use…

Anyone have CFA3, GRLV, or headphone protector boards available for sale? Thanks!

What can I use to get rid of nasty sticker/tape goo residue without harming a nice surface? The item in question is the VAC-1 (VDA-2, VHP-2, whatever) and I'm talking about the nice smooth finish on the front plate.

Well as Ti said it "the cat is out of the bag" so I thought I'd put it here: AMB and MisterX are working on the y2, an add-on board to the y1 that adds ASRC, WM8741/2 DAC to the y1) There is a thread about it on HF's DIY forum. Link

I have a pair of "Cheap" helping hands with magnifier. These things you have to have but are never quite right. I also have a Panavise that I use them in conjunction with. They end up breaking and the hinges and clamps for the clips are dodgy at best. Are there any "Good" or "excellent" ones out there? I have to have the magnifier. I can't pay $300 for a set, but I would be willing to invest more than the $5.95 you pay now to get junk.