Do It Yourself

I think there are enough woodworkers on HC to warrant a thread now. Between Myself, Milo (AKA Al, AKA DOTU), Naaman, Doug, Jeff, Marc and I know there are others. I thought it might be nice to have a thread to keep up to date on various projects, new tools, new accessories and new enovations. For example: A new enovation I find very interesting, is a new blade stop safety system from The Felder Group. Like the system from SawStop, it's immediate, and it drops the blade out of the way before any damage to digits can be done. Unlike the SawStop system, it doesn't use a sacrificial cartridge to stop the blade. Don't get me wrong, the SawStop system was nothing short of …

The end of a headphone plug broke off in one of my headphone amps that has a locking Neutrik 1/4" headphone jack. I tried the straw trick, and even the screw trick (gently), all to no avail. Considering the glue/heat trick. Am I fucked (and not in a good way), or is there another technique I should consider trying to get the piece out? Any inputs are appreciated. TIA.

Can't seem to find any info or examples of these in use, but someone here must have tried them. I have found that buffers on the output of a Muses electronic volume control works very well and had good results with Sjöström Audio diamond buffers but Kevin's little PCB's might be even more compact. Can anyone remember a thread or post where these were introduced? They are a very simple circuit and could possibly do with some extra PSRR with caps right on the power pins, they are so compact I have found a neat way to stack them, in the pics below is a quad channel balanced stack, all the PBCs are connected through the power pins, leaving the i/o's separate. E…

Hi all, I've been more and more interested in building my own amp after having built a relatively simple Elekit amp. I've been reading through the KGSSHV and KGSSHV Carbon build threads and I think I've found the google drives for the schematics and various documents, but it's still a bit confusing where to begin, and I'm not entirely sure I should jump right into trying to build a KGSSHV Carbon. I'm also unclear where one sources the PCBs for any of those builds - seems like various members hold extras and there are some floating around on eBay of dubious origin. Anyway, I'm not exactly certain what build would be good to start out with, or what the differences are …

I just boought a locky_z curve tracer https://www.ebay.com/itm/Locky-z-2019-Curve-tracer/114233327020?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 Has anyone here used one or have experience with one? I was reading on another forum that the ones he's built with used parts sometimes fail. They're also swapping out the relays, electrolitic caps, op amps, voltage ref, and some of the resistors for better accuracy. I'm waiting on a power supply so can't use it just yet.

In progress Amp design by me, power supply designs and circuit board layout by kerry, support by birgir +/-300 volt power supplies. complementary push pull all bipolar design with cmos style multiplying current mirror.

Hi all, I purchased a KGSSHV recently, and whilst overall i'm very pleased with the sound, the pot installed is cheap and unfortunately has some balance issues at lower volumes. It looks to be a modular type pot, and bizarrely has 4 lugs per channel rather than 3. I've managed to get hold of what I'm told is a rather nice TKD 4CP 2500 pot, which has three lugs per channel. Can anyone offer some advice on the correct way to go about wiring it in? Looking at the old pot, there looks to be a set of bridged lugs on the far right which go directly to a piece of wire bridging the inputs at the back of the amp, as well as left/right input and output wires from t…

Has any one of you done something like this, accommodating a pair of RCAs and a pair of XLRs, with the appropriate switching for these? I know I'll get told to just use the Neutrik or whatever RCA->XLR adapters for this, but I was thinking about doing up a PCB with a pair of something like the Neutrik NC3MAV/FAV and a pair of RCAs. Has anyone ever used the vertical Vampire RCAs (pcb2f/s)? They don't list any dimensions or PCB layout for these, but just wondering height-wise if these could work well? I had thought I would probably use relay switching instead of a mechanical switch, as the 4PDT are a PITA to wire up, but I suppose just going into a board with c…

For the Carbon I am building, the user would like to be able to bypass the volume pot, but would like it switchable for when the source doesn't have a volume control. I had initially told him no problem, this will be easy. The more I thought about it, I realized it isn't quite as easy as I had surmised. Simply shorting the input to the output (wiper) would still result in potentially bad things depending upon where the pot was in its rotation. Since I had already done the pot adapter boards for the gb awhile ago, I started with one of those for pcb layout (the pot I am going to use is a TKD CP2500 4 channel). My initial thought was to take the pot completely out…

I have had my beloved ATH-L3000 for many years now. It has developed a frayed cable around the split: I am seeking advice as to possible next steps. Right now, it is not causing any performance issue (has not broken connection). As a safety measure, I have wrapped the entire junction with some blue painters tape to hold it all in place - not ideal. Questions: Is a replacement original cable (NOS) available? - checked with AT - they had no real response - said send it in.. Try to repair the junction? - not much room to work and secure. Is a compatible replacement available (equal quality)? Possible third party cable replaceme…

Does anyone have or know where I can find a board that would let me mount a single or side by side Amveco PC mount low profile toroidial transformers? I'm just looking for a board that would have AC in and out going to terminal blocks and allow the use of standoffs. Amveco PC mount low profile 50VA toroidial transformers https://talema.com/wp-content/uploads/datasheets/70000K-72400K.pdf If not, I'd gladly pay someone for their time to lay out a board for me. Something like the pic in here

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…

Hello everyone, hope everything doing very well today. Few days ago I found two transformers in my dungeon, which named by my wife. I mentioned it has 16V out and double 110V in, so I guess perhaps could make something like stax srd-7. Then I made a pcb and give most places to voltage doubling rectifier, as same as srd-7, and... it works. Well somehow the bias unable to reach 580V, only around 490V, the sound quality, of course, bass section bit weak, so I have to turn the EQ on, then everything fantastic. BOM: 2 30W transformers 110-0-110 in 16V out, 1 50W transformer 220V in 110V out. 1 fuse @200ma 6 0.1uf 630…

This topic has needed its own thread for quite some time (years), so starting one. I may see if I can get a mode to move some of the posts here (Carbon thread, not sure where else they are littered). 11 hours ago, Pars said: GRHV question: I'm building a pair of the singles intended for 400V output. On the BOM I have, there are 2 680uf caps for each board; 1 is a 550V caP, the other a 450V cap. I presume the 550V would go right after the rectifiers in the schematic, and the 450V on the output. The BOM that was posted by jamesmking uses 4 x 470uf 550V Kemets. Is there much difference between the 680uf and 470uf in terms of sound or anything? BTW,…

Nectar Sound, purveyor of the Pollinator and now the Hive headphones, has a DIY amp published on the website. I reached out and picked up a PCB so I can build this low cost energizer and see how it stacks up against my SRM-252S. Attached is the schematic, BOM, image of a completed amp, and hook-up guide. You can also access everything on the Nectar Sound website. Sajeev has updated the board slightly from the images attached to hold a pair of CL-90 inrush limiters to prevent blowing a fuse on start-up. I'm in the process of gathering the parts now, but wanted to post this to archive the build and see if anyone else was building (or has built) one. Nectar1p0_Headp…

Is this the new product for high voltage transistors ofr electrostatic headphone amplifiers? https://www.akhansemi.com/company.html

Well cheap compared to all the monster amps out there So correctly done, one would do the Uberamp2-Raal edition, which results in something really big,heavy and lot of heat. And a custom and large chassis, and a pile of $$$ This is a bit cheaper and easy enough for just about anyone to do. From the Ti Opa541 datasheet, showing paralled opamps good for at least 7 amps rms of output into anything including a dead short... Designed to be mounted directly to the heatsink, amp board right angle to the heatsink. All wires to the board directly soldered, 4 oz copper highly recommended. Power supplies are a minimum of 24V at 10 amps, like this, but more …

Hi All, I have been going cross-eyed of late poring through the various threads for the projects required to get a complete amp together and hoping to get a few pointers. I was originally looking at building a Dynalo based amp but after some feedback from Pars and others I had a look at the CFA2/3 boards and think I have decided to go with a CFA3 based build. I am going to build a balanced in / balanced out setup in dual mono so for the amp boards, it will be 2 x CFA3 (based on 89753654_cfp3rssfixedssw-CADCAM.zip) - I am pretty comfortable that this seems to be the most recent version of the CFA3 board. Where things seem to get a bit interesting is the…

Anyone here have experience with one of these? Price is right, but likely too good to be true? https://volumio.org/product/allo-stepped-attenuator/

Wondering what type of plastic Stax uses for the (black) jacks on their amps. Or if anyone knows of a black plastic or material that is machinable and plays nice with high voltage. I don't know what Stax uses, thought it might be bakelite as it is hard and brittle but it fails the "409" test for bakelite and a sliver that I cut from one floats as well (bakelite is heavier than water). You can sometimes identify plastics by the way they burn. Couldn't ignite the (tiny) slivers that I had. Possibly a phenolic smell after heating, might be a lower density resin related to bakelite. DIY jacks are usually made from white teflon (or delrin). Black coloured materials t…

As many of you know, I for one have stopped releasing all new designs for a few years now after I got fed up with people building crap and claiming it was somehow connected to Kevin or I. Now this also means I don't release the PCB's for many of the older projects as I want to change something and often... make them smaller. So this hasn't stopped people selling crap with our circuits but at least they don't get any of the updates. Now here is an amp I saw come up for sale in Japan a while ago. The new owner contacted Kevin to try and trouble shoot it but yeah, we don't offer any real help with these things. Something about the PSU did peak my interest so when …

Keeping in mind Kevin Gilmore's design rules i have insomnia about stabilizing common mode of JFET input stage without sacrificing CMRR or straight referencing it to the amplifier/source ground. So, check attached schematic. While keeping straightforward signal flow aka "Gilmore's gesign rule" it also have second control loop which helps SuSy amps to maintain output common mode near ground potential.

Hi All: This is the build thread for the Kerry design PSU. I posted BOM and schematic with Kerry's permission here and will be posting more information including photos of my test build. My test build use the partially-assembled GRHV boards. I soldered in the the pass transistor and the resistors to set up my desired output voltage. The voltages, timer all tested as expected without load. Fire up your soldering irons and happy building! GRHVBase-v2-production.pdf GRHVBase-BOM - V2 production.xlsx

Folks, I replaced all the electrolytic capacitors in my SRM-600. I can't say for sure if this has happened before, but this (photo) capacitor at 10V 4700uF is heating up. Not very much, around 55C. The headphones aren't plugged in. Can you tell me if this capacitor is in normal operation? Does it have to warm up? My SRM-600 for 230V voltage. First, I supplied a cheap Jamicon TKR472M1AJ26 capacitor. It was heating up.Then I decided to place EEUFR1A472L Panasonic Low ESR capacitor. However, it's warming up, too. I checked the diodes next to it - they're not broke. On the cap about 7V. Any other caps running cold. Only 4700uF/10V run…

Does anyone have schematics for either the Gold (balanced?) or the unbalanced version of these? I told a person I dealt with (diyaudio user) that I thought they might be available (and told him why bother), but his interest is just in the front end section as a preamp). I saw what is available on the eservice info site, but can't remember my login there. The user says he has some incomplete schematics with pencil markings on them. I had the attached jpeg, but think this could be what he already has. Thanks for anything you can find.