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…

finally. higher signal to noise ratio, more than 110db. takes signals up to 20 volts peak to peak unbalanced, 40v peak to peak balanced. no input attenuator that adds noise for those stupidly high voltage dacs. ( requires 30v power supplies) (volume control in the middle) thd about .005% no feedback. work in progress 4 layer board. preamp2025f.PDF

I was hunting around in the garage last night and came across an old t-amp I put together many moons ago and it has a TKD pot attached, I bought it quite a while ago and don't recall where from. Are these any good? It's 50k so I figured it'd probably be ok for either the SS I'm about to start or maybe even the Dyna. I can't find too much info on it and nobody mentions them. looks the same as this which is listed as a Ko-on. Anyone familiar with these?

BASS CAPACITOR Ok, someone explain what a digital capacitor is? Thanks.

MachMat VCCS filament supply Gary Pimm CCS Design by HF member Roam, traced out by me while I was over at his place to pick up transformers for my own project. Yes I have his permission to post it. I spent about 20-30 minutes listening to it out of his Capitole CDP and my RS1, this amp is good, stupid good, but also stupid expensive thanks to the transformers and Emission Labs AD1 tubes. He says he has what should be a slightly purer version in the works using WE 205E's on the front end, but it may sacrifice a bit of bandwidth. No PSU schematic yet as he's still waiting for some parts to come in so it's running off an adjustable benchtop PSU. Can also be built with…

For the moment I have the beta and the EHHA amps, two boards each but only one Sigma. Until I get another sigma they are going to share. The sigma has four outputs, enough for the boards. Now, if I want to run both amps together is there any reason not to? I can switch on the heaters before the amps to warm up the EHHA. Any problems so far? Not ideal but I'm not worried about ideal at this point, just functionality. There's also the option of running the sigma output pairs through switches to turn one or the other pair off. Any thoughts on the best and safest way to do this or is what I suggested first fine?

There seems to be some consensus on the voltage requirements for electrostatic headphone amps. Nearly all of the commercially available designs put out between 1000 and 1600 volts peak-to-peak, a range of about 4 dB. The legendary Stax SRM-T2 was specified to put out a bit more, close to 1800 volts peak-to-peak, which is 1 dB higher. This would be equivalent to almost all loudspeaker amplifiers putting out between 50 and 125 watts, with the T2 being like a 160 watt amplifier. However, there hasn’t been much discussion on the current demands for electrostatic headphone amps. Output stage currents in commercial amplifiers have run between 2 mA/channel (Koss ES950) a…

I'm thinking about using the 4 gang ALPS pot for my dynahi. I want to mount it on a pcb but I don't see any available so I thought if I took two epsilon 27 boards I could make one. The first board would fit the front, the second board looks like it would need the front trimmed off to fit the back section. The grounds are tied together on those boards so I'm not sure how that comes into play since I've never wired a pot for balanced audio before. How do you wire a volume pot for balanced audio and do you think this would work?

As Luvdunhill has a limit of 100 total for his mini-GB, and the the count was well above 100 not counting myself and luvdunhill, I've got a quote from Trendsetter at 5USD/ea, at minimum of 100, I've decided to organize a GB for those who still wants the LSK389B at 5USD/each, state your interest here At this point in time there are almost 100. Please be aware that the GB started as for SOIC-8 package alone. I have added the TO-71 to the spreadsheet. 20160120: GROUP BUY CLOSED

I am in need of a preamp with some gain and I was thinking about a DIY tube preamp. Doesn't need to have crazy high gain as the power amps will have voltage gain as well. Right now what looks attractive is the K&K Audio active output stage. The level 2 kit comes with most parts including the OPTs. Looks like a fairly good design to me? If not any other suggestions? Preferably something that is well documented.

I've seen posts here and there commenting on the difficulty of recabling the K1000, and it's definitely not something a novice DIYer should attempt, but I think most of the fear and confusion over recabling them comes from their unusual construction and lack of information regarding safe disassembly. I hope this guide will help clear up the process for advanced DIYers who are already comfortable recabling normal headphones, but wary about working on the K1000. A few notes before I begin... You should have your cable already built and ready to go before starting disassembly, so the K1000 is not left in a partially disassembled state, and complete the work on one ears…

and about time... I’ve been keenly anticipating this . Here’s a link for those that are interested or have missed the news; http://www.amb.org/forum/gamma3-high-resolution-dac-development-t2656.html

I've read as much as a I on the topic and there seems to be fair arguments for both amps. It seems HC fosters a fair few with impressions of both amps, so I figured I'd ask here for opinions. My situation is this: I don't plan to begin building/organising the eventual winner of this topic for at least 5 months, but as the changing of hands of djgardner's KG amp stash to AMB has offered me a wonderful oppurtunity. Get the boards and the majority of the transistors from one place, and Ti even offers matching which would cut down on alot of the hassle. All in all, this may be the best opportunity I have to build a dynahi. But I don't want to build it if the β22 would …

Yet another stax project soon. A lot of people are going to want this i think. Birgir knows what it is, and had better not drop any hints hint: diffuse field.

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've been lending a hand with board layouts for a few projects, notably for a build of Kevin Gilmore's DynaFET design, and doing so made me realize two things: (a) there aren't any DIY projects for amps with a truly high-end feature set, and ( I want one, but I can't really afford it. The DIY crowd has some amazing analog designers and has produced some really astounding designs, but the supporting and surrounding circuitry often isn't much more than a pot and maybe a selector switch, and sometimes a power LED or relay control circuit. There's so much more that could be done to make amps more convenient, self-monitoring, and just plain nifty. So I decided that this was an…

so yesterday this showed up quoting alex... "In a nutshell, the Liquid Carbon is a fully-discrete, fully-balanced, transportable solid-state headphone amplifier that is capable of driving all but the most demanding of headphones - delivering satisfying levels and offering superb driver control for exceptional detail and linearity." lets run that thru fact check for a second. yep... "Liar Liar Pants on Fire" fully balanced? nope, not in the way that any truly differential amplifier would be. (like any of the super symmetry variants) and absolutely no common mode rejection. fully-disc…

I have a Nice 20" Craftsman D.P. I bought recently. So I'm drilling (butchering) a computer case presently and the tapered chuck spindle keeps dropping off! I cleaned it up real well and have seated it against a blcok of wood with some pressure. Fell out pretty easy. I retracted the chuck and pounded it in with a dead blow hammer. Didn't help. Then took a small masonry hammer and some wood and pounded the crap out of it I thought. Still fell out. What's the super secret way of wedging that gadget in there!

Twisted Pear Audio (Russ and I) are holding a raffle to raise money for Doctors Without Borders relief work in Haiti. I have set up a page on our site here: Relief Raffle for Haiti The Grand Prize for the raffle is a complete kits to build a Buffalo II-based digital preamp. This consists of a BuffaloII module, IVY-II I/V Stage, Placid power supply kits for both, an S/PDIF Mux kit, a Volumite Kit for the BuffaloII, and a pair of transformers. We are also giving away the following runner-up prizes: An Opus S/PDIF (or USB) Dual-Mono DAC Combination A COD S/PDIF (or USB) Dual-Mono DAC Combination A Ventus Headphone Amp Kit Each raffle ticket is $10. 100…

topping dx5ii schematic class B output stage. and they seem to be proud of this crap. discuss dx5ii.PDF

So, what happens when I have a new (to me) lathe, some left over mahogany and nothing better to do? Yup, those are my HF-1 on the bannana stand, and my maple woodied 325s, which are for sale. But what are those other ones? I call them the HF-1000 I was making some standard woody cups and figured I'd have a run at something resembling the GS-1000 (which I've never seen in person). The mahogany I had was way too dry and none of the standard cups came out well (actually only one survived!), but the goofy mushroom cups came out well enough. So after I finished turning them, Nate gave me a hand drilling them out and we decided to see how they'd look on his …

I've been thinking about upgrading to a better soldering station. I am just a hobbyst so the tool is mostly for DIY work. I started out wanting to limit my budget to $200 US. As always the case, once I started reading stuff on the web, I am more and more tempted by those that are way over my budget. Right now, I am looking seriously at: 1. A JBC CD-1BD for around $400 2. A Hakko FX951-66 for around $260 I would love to hear your experience, experience and recommendations. Thanks!

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:

So for a little while now my Sony DAS-R1 has had a problem with the left channel cutting out. It used to get better by itself after a minute or so, then it needed longer. Now I have the lid unscrewed all the time and give it a wee tap. While this cures the symptom it doesn't cure the disease and the wee tap is now turning into a prod, before I know it, I'll be using a frame hammer. I'd like to fix this myself however I only just know which end of a soldering iron plugs into the mains and which end you use to burn your fingers touch against things to heat them up. I've looked under the board and I cannot see any obviously broken connections. I am fairly certain that …

I've been getting back into guitar lately and think I'll want to put together an amp relatively soon to replace the cheap starter I'm using. Anyone have any ideas on a good one to put together?