Do It Yourself

If it works it will be pretty cool: Xerox announces silver ink, keeps printable electronics dream alive

Kevin did not show Forward Voltage of LEDs in his designe,and I think it will not be 1.5V . so I want to konw it's 1.7V or 1.8V?

If I take say 1 120 Ohm 5 watt wire wound resistor for each channel that's sufficient for a dummy load correct?

So, I want to build an L-Pad based headphone adapter so I can connect headphones to the speaker outputs of an amp. This is mainly for S&Gs, but if it works great then I have the added bonus of having my innate and poverty-enhanced cheapness vindicated. I was planning to use this information from Meier to optimize the impedance for my headphones: http://www.meier-audio.homepage.t-online.de/ - click on "tips and tricks" and look under the impedance optimization title. One thing I can't figure out (yes, I'm challenged with these types of calculations) is how many watts the resistors should need to be able to disspate. Let's assume I have an amp that maxes out aro…

Hello, I have a Cavalli CTH amp that I built about 8-9 years ago. During that time I tinkered with it and had to rebuild parts of it once or twice, and then again rewired it and installed a new volume pot. Long story short, I burned out the input ground (IG) connection on the board. I was able to get it to connect to some degree, or so I though, but recently when trying to bring it back to life it came off again. I wanted to ask advice on how I might go about repairing this. The IG seems isolated from rest of the board, so am wondering if I can just install a isolated nylon spacer on the chassis and put a metal screw on it, run IG wire to that. IG currently is connec…

How crazy lazy would it be for me to buy 3 of these and slap them into an enclosure, with a single big ass toroid transformer? It would be an 6 channel amp, I'd probably not use the 6th channel, as my speaker set up is 5.1 right now. Any recommendations for a Toroid feeding 3 of these? AMP5 kit - Tripath TA2022 41Hz Audio:AMP5 kit Although, I might just get one for starters and build a small desktop amp for 2 channel speaker set up for my computer workstation. -Ed

Hey guys, I need to put together a wallwart for a project I'm working on. Is there any place that sells empty wallwarts you can put your own traffo in? I'm looking to get a 24-36vac center-tapped output. Any suggestions on a plug with three contacts to use for it, also? -edit- found an empty shell and a suitable traffo at jameco. Any ideas on a plug?

I have a pair of 2n5457/5458 JFETs on a small board as part of a bias scheme for a 12AX7. The circuit also has a 9v battery. I cannot get the voltage dialed down, so I checked the JFETs. The resistance from gate to source (and gate to drain) read the same in both directions: roughly 1k ohm. These are dead, aren't they?

Anyone here gander a guess (or someone that's built one) how difficult it is to build (battery version)? I wrote off getting one since I didn't want to wait for the Digikey order and the order from Hagerman but someone is selling complete kits on ebay so I'm thinking I might as well do it. And it might just outperform the NAD PP-2 for less.

This is for use on my balanced beta22, the zobel networks described at amb`s beta22 site are: 22Ω 2W 5% metal oxide power resistor and 0.047

I'm looking to give my headphone cables a more professional look like this http://redsecta.files.wordpress.com/2012/03/650cable.jpg I want to find splitters like this guy used

Does anyone know where I can get instructions for adjusting the bias on an SRM-T1? I would like to replace the tubes and it seemed logical to find out. Then again, maybe not. Who cares? Seriously though, any help would be appreciated.

I recently picked up a wireless charger for my phone that works well aside from the annoying inductor whine. I was thinking of dropping some hot glue on it to dampen the noise, but thought maybe folks here might have a better suggestion of what to use. Any suggestions on a better damping material than hot glue? Thanks

As above. The 2 DACs I have already haa digital volume control which I believe are provided by the AKM/ESS chip. Thanks

So I have a Bijou built by dBel84 (Don) and am curious about the negative feedback. With the pot turned all the way down (7 oclock) it seems to have no negative feedback and is perfect for my AKG 340's . As you turn the pot clockwise you get less and less sound. Am I supposed to turn the negative feedback up when using Grado's and Ultrasones ( I know everybody at head-case loves Ultrasones) If I turn it up too much it seems to loose a lot of the lushness of the amp. I am still trying to figure out the best spot for my low impendence phones. Anybody got any advice? Chris

Any of you ever across this stuff? Discrete opamps and 78xx/79xx Vregs? https://sparkoslabs.com/ Wonder if the regs are any good and how they compare to Amb's o78/o79?

Members pay a fee and can use some expensive DIY equipment: Ping - At TechShops, Do-It-Yourselfers Get to Use Expensive Tools - NYTimes.com

Hey gang- When I bought my Hagerman Bugle a while back, Jim set the gain high so it would work with the DL-103. While the sound was excellent, I found there was too much hiss present in my setup, and went to a SUT + MM phono combo. Today I was looking at the Bugle and thinking it would be nice to get the gain lowered so that I could run it from my SUT and compare it to my Bottlehead Seduction. Can any friendly DIYer give me a rough idea of what would have to be done to get the gain on this sucker back down to stock levels?

Toob n00b alert!! Is it detrimental in any significant way to run heaters at 12 and 6V instead of 12.6 and 6.3V? I'm running a 12V 3.75A regulated supply from an old monitor and it works and sounds fine but wanted to know if there was anything I need to be aware of doing this.

Interesting thread that has popped up from some recent controversy in Stereophile surround the Halco amps. A few heavy-weights are in on this discussion, so it should be interesting! http://www.diyaudio.com/forums/showthread.php?s=&postid=1404200

So I recently picked up a couple of niche audio control modules. They're unusual passive summing boxes/mixers controlled entirely by midi. It's 8 inputs, 8 outputs, and then a summed out. The 8 inputs and 8 outputs are TS unbalanced, with a TRS out that's 1-4 TS and 5-8 RS. If I were to make an XLR patch panel that has 4 XLR inputs that send each channel to pins 1/2 and 1/3 as TS cables, would this result in a 4 channel balanced mono summing mixer?

Hi, everybody! I'm novice here and signup being impressed mister Kevin Gilmore designs. First of all - thanks to him for making designs opened! Now i'm thinking about building Dynahi at a different manner than author. The main concept is to put overall amp in a comparatively small case such 3209: http://m.ebay.co.uk/itm/3209-class-A-Full-Aluminum-amplifier-Enclosure-AMP-case-both-side-heatsink-/271986781371?nav=SEARCH So, PCBs must be rerouted. Here i want to offer another building idea, best to understand by photo and renders (for understanding dimensions - caps are 18 mm diameter and 35 mm height): There are several benefits in such layout. 1.…

Dunno if anyone here might want to say something in this thread: http://www.head-fi.org/t/707823/intellectual-property-giveaway-on-the-discovery-of-terminal-illness#post_10316570 But I will certainly miss him.

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…

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 …