Do It Yourself

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

I have my little lathe on order and it's a cheap POS cos I'm broke so the question I have is..... If you too were a broke cheap-ass, what would be the one chisel you'd buy for doing stuff like woody cups and the like? I can't afford much so It needs to be small enough for detail and tough enough for roughing out the basic shape. Suggestions?

I enjoy thinking about different ways to accomplish the often-overlapping electromechanical goals of audio devices. Every few years I get to considering electrostatic headphone connectors, and every time I end up finding the same collection of vintage part numbers, shared experiences, and a few useful drawings that can be put together to probably lead to a functional socket or plug, if you want to make one yourself. I appreciate and have used that information, and now I'd like to consolidate it and create some actual specifications to help anyone trying to make a plug or socket. The most useful thing to start with would be plug specs. Pin diameter, length, pin circl…

I'm modding an Adcom CD player for a member here, installing a pair of Colin's I/V boards (player is balanced), and am debating on how and where to connect ground on these to the main board and power. These boards have on-board shunt regulators, so I am tapping power from the main filter caps right after the rectifiers for the 2 +/-15V power supplies for the analog section on the main board. AFAIK, it is usually not a good idea to connect more than 1 ground per board. The options I see are: Ground the boards through the power connector Ground the input of the boards Ground the output of the boards Currently, I am leaning towards #1, thinking that noise from the shunt r…

I bought this Audio Note Kits HE-6 headphone amp and had it built by a well known Audio Note kit builder, digitalpete. The amp sounds great with planar headphones but I have a problem I need help with. The volume control has a terrible scratch noise when adjusting the volume while music is playing. It will also produce the scratchy noise when the volume control is even touched while music is playing. When nothing is playing the sound is there but barely audible. I emailed digitalpete and he wants me to ship the amp back to put in a new volume pot. In looking at the khozmo volume pot it looks like there are only 11 connections to solder and all are easily accessible so…

Has anyone played with biasing capacitors that normally only see AC with a small amount of DC? I know some commercial speaker manufacturers have been doing this for a while (Vandersteen, Infinity, JBL, etc. comes to mind) usually using a battery and often accompanied by fancy marketing speak ("Charge-Coupled Linear Definition Dividing Network"). There is a lot of ink spilled on the subject, but what do you say?

Now this is my first time on this forum so hi everyone! Right so the main business is that I've always stuck with Skullcandy for comfort and style, but i always get the same problem over and over again(no matter what skullcandies they are!) and that is the cable goes dodgy up in the speaker can. this happened with 2 pairs of skullcrushers i bought and because i live in the UK their warranty doesn't extend to over here. bottom line is , I've soldered the cables back down in the can but the sound still cuts off regularly, is there a smarter way to reconnect the cables inside? or is it worth completely replacing the cables? only problem being is that the subwoofer is c…

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

Now for the dumb questions. I've never built a speaker cable. I want to do something quick and easy to test my AE2 speakers to see if the stock cable is picking up RF. Can I just use two separate runs of Mogami, using all four conductors? I won't be terminating at this point, just twisting the strands. Is this basic premise correct?

I'v decided to build a balaced M3 and I would like to see how others may have implmemented swithchable gain and different component choices. Thanks

Here's the APC H15 I got recently: I wanted black, but I got the silver for $200 less. Is there an easy way to paint it black? The face plate is some sort of metal. Any ideas about how to make it, well, less silvery?

Well its done K701 recabled with Mogami 2534 Neglex Copper Quad Mic Cable. Nate had a supply of it, along with the black 3/16" Nylon Multifilament techflex, so I asked him if he could strip the jacket and shield off the Mogami, and feed it through the techflex, which he graciously did Here are some pics (some not so good) of the job: Stock cable Mogami laid into the K701 frame Preparing the 4-pin XLR end of the cable A happy ending On the other ear phone there are two small wires which I have not replaced, but I may leave them for now.

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…

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.

So, I have 4 X Beta 22 Amp board kit + 2 X Sigma 22 Power Supply kit from Glass Jar Audio in a two HI-FI2000 slim line 2U case with aluminum top and base plate. My idea is to use 100mA quiescent current to keep the temperature a bit lower, but should I drill holes to those base plates? Would it actually help to keep those temperatures lower with those covers? Or should I just order more vented custom aluminum covers from Modushop? Cases: Top and base 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've read a few times that the EnABL process can be applied to Grado headphones, particularly the metal housings ones. I've had my modded SR100 since mid march and I'm wondering if anybody ever tried that on the black or silver vintage SR325 housings or the MS2/HP1000/PS1 and what were the final results ?? I found this paper to be quite interesting : http://www.positive-feedback.com/Issue21/standingwaves.htm Also, I'm gonna buy some Dynamat Extreme for the housings vibrations dampening, anybody knows where are the key places to apply the black tacky-like substance ?! Is there anyone who can enlighten me here ? That would be really appreciated !

Hi all, As part of my home theater build, have decided to go for 3 way actives for front LCR… so, need to build 9 power amps for fronts and 8 amps for surrounds… to pair up with my Sherbourn PT-7020A pre/pro. I needed something as easy, but more powerful. This is when I and my friend John found the datasheet of TDA7293. This IC can run up to 100V, low distortion, and can easily be paralleled. Having built single chip amp and extensive listening TDA7293 is my favorites for IC power amp applications. I have been looking for a source of PCBs using parallel TDA7293s… there are not many out there that you can buy. We then decided to do our own PCB. Our schematic is almost…

Staxen amps (at least the Mafia versions) use either el34 or 6S4 (with the Megatron including some 12's ...) I sold my tube tester years ago after getting out of SET's and such. What do you all think about testing these tubes? Is there a simple test rig, perhaps even 'in circuit' we can use to test the tubes without having to deal with a full blown tester?

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…

I came home from out of state on Sunday and noticed my preamp display was awry (L-R arrows flashing, mute on, front panel non-responsive). Last night I took a look at it and it seemed to return to normal upon running signal thru it (CD->pre->headphone amp). This is a Classe CP-50, probably mid-90s vintage. From reading the owners manual, the display I was seeing is what is supposed to be there after a power outage, but I thought after 45 seconds or so it was supposed to go back to normal? At any rate, I have it open now and think I will recap it. Most, if not all original caps are Nichicon VX(M), 85C, standard series, 2000 hour life (from what I can tell). This…

Hi, I know there are many schematics like this but this aims to be a very cheap amplifier for the estats and it should be better than the SRD boxes. The power supply for tube has +-300 V and there will be four windings on transformer for heaters. I know I can not trust the simulation so I think it will have a maximum output voltage around 500 V peak to peak with some luck, probably less. I took the CSS from SRX+, so credit goes to JimL. Output current is set to 6mA per one output. So 12mA per channel. I added small feedback to stabilize it with 470k resistors. My goal is to make a small cheap amplifier. Voltage output is rather small than other amps bu…

I bought a replacement tip for the iron labeled Aoyue brand but seller claims works with the Hakko. When I replaced it in the iron the replacement tip spins sort of freely (I can rotate it with a slight bit of force) even with the nut for the protective metal guard screwed in as tightly as it will go. Is it supposed to do this? Thanks guys.

I am having some PCBs made, and I have a 3.5" x 3.9" spot left empty on the panel. If anyone has a small board they want made, and it will fit within that spot (that size or smaller), I am happy to add it. Board will be 2oz copper and RoHS if that matters. Cost is Free. The only complication is that I am sending the order in late Sunday, or possibly very early Monday, so I'd need the files before then. I guess the other complication is that if you did not do the board in Eagle, there is no guarantee it will work. We'll see.

Of course it's not an exact clone due to several changes, but I was wondering what opinions of the project might be. Check it out here/. I'm considering taking that and doing some mods to it or taking the Buffalo and building a DAC around that, or maybe even the PCM1794 or PCM1704. I'm just throwing this out here to see what kind of opinion I get.