Do It Yourself

Hey all , so this is my first post here so sorry if its not up to par. Recently i bought a Srm-006t amp 404 signature combo . I loved the sound but it seriously lacked volume . I replaced the tubes with a new set of EH tubes .. but aside from a uptake in tone .. I didn't get any extra volume . I started searching Google for mods to this energizer and came across a post by Kevin about a cascade mod for this amp and mention of an article in Audio Express July 2017 edition by James Lin. In the thread i was reading i saw that a board had been designed (im really not a fan of point to point electronics) and messaged Kevin Gilmore about it , He said he was all out…

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'm trying to make a Super Symmetry Dynahi (not dynalo) the best possible way. (without getting in the ridiculous). Anyone could direct me to the up to date gerber files, a BOM, any other resources are also appreciated. Also if any of you previous builders have recommendation on best practices and what to avoid while making the susy please share ! Thanks

2SC4686 can be replaced by C5502D. What is the replacement of 2SA1968 for gods?

What is the replacement of the stable pressure pipe? Z4 Anybody know, thank you! STAX SRM-007TA Z3, Z4 Bose sealed diode，

Hi guys,here is my hybrid e-stat amp design using only ONE cascoded voltage gain stage and a solidstate buffer which translate the high output impedance of the voltage gain stage into low impedance. The cascode voltage gain stage uses an ECC88 as input tube, for its low noise and high transconductance, and a 6SN7GTA/GTB to bear the high voltage(anode voltage is around 350V to get reasonable voltage swing). This stage will get approximately 200x, or 46dB gain. And please note that, the grids of ECC88 is biased at around -420V, so you can't really go DC-coupled, coupling capacitors or transformers have to be used. As most digital source components today have an ou…

Someone, who will remain unnamed here, got me interested in building a Megatron I got quotes back from the fab houses. If we can get 10 sets we can get the cost per board down to just under $40 USD (plus shipping from me to the participant). The PCB is 228mm x 228mm and will be 2mm thick with 4oz copper. I did some research and the only obsolete/hard-to-get part is the 4 2SA1968 which Kevin confirmed can be replace with KSA1156 mounted backwards. The board also uses 2 2SC1815 or MPSW06. I have a stack of the 2SC1815 so I am happy to supply them to the GB participants that need them (no cost). Please respond here if you are interested. Thanks!

Sorry to start a new topic on this, but I thought if I posted it on a previous thread it would get lost. The issue with the original power supply was that it was noisy at times. I had originally measured < 2 mV power supply noise, and 3 - 5 mV noise at the amp outputs. But on re-measuring, the power supply noise was > 5 mV with the amp output noise measuring around 50 mV. In fact, the noise measured before and after the regulator was similar. Thinking the regulator was noisy, it was rebuilt with new devices, without improvement. Since the current source (CCS) in the positive supply line should block noise from the raw positive supply, the likely …

For the dynahi I am building (in the builds thread), I would like to use one of the vandal switches (like a Bulgin) in blue ring. What would you recommend, and if it needs anything to run it (SS relay, E24 board or whatever) note any recommendations there also. Not sure I want to mess with another transformer/PCB, but will if it is worth it. Case is a hifi2000 Pessante Dis. I have both silver and black faceplates, but was leaning towards black for this one. I will have the faceplate done by either FPE or the other place on the east coast (if I can figure their S/W out Thanks for any thoughts.

My previous query(ies) may have gotten buried. Given the somewhat religious fervor this topic seems to generate on other forums (without much technical justification for the most part; just assumption), I would like to know people's thoughts on this. My take from other reading seems to be if not shunt then you are a) a dumb ass, or b ) you just don't appreciate the best. I did read a critique/analysis on topic that discussed shunts presenting a more uniform impedance to the load, but then went into a discussion of a push-pull relationship via a shunt, versus a push only relationship with a linear reg. My specific interest is in a Salas shunt vs. GRLV plus for a phono…

as most of us know that beats studios require batteries to properly work. i got my hand on a pair of demo/Retail version of beats studios. these headphones arent wired to have batteries placed in them and the audio input ccable is hard wired to avoid theft. i got a good deal on these, with a spliced cable, what im trying to do here is wire them up so i can use them. This picture shows what the wires look like once stripped of the insulation. two wires one copper and one copper braided with a blue wire. inside the copper braided wire are two wires, one black and one blie, my guess is that these are for the external power source the green and red wires were wrapped i…

Hi all, First of all let me begin to say i am a beginner wit some detailed instuction and BOM i come pretty far. Just finished my O2 and ready for a new challange. I have a new DAP on the way with balanced output so i thought a Balanced in to out would be a great additition. So i have a few options which i cant decide which one to build. -Krell KSA5 Clone -Audiotechnica AT-HA5000 clone - "The Wire" bal-bal amplifier OR the Dynalo which is pretty hard to research because his website is down. This link for instance http://gilmore.chem.northwestern.edu/boards/ My headphones are Audeze Sine and HD650. So not that much dem…

I think I'm moving on from Par-Metal. I can't get them on the phone any more and email response is spoty. Has anyone found a chassis supplier on Ebay that can sell something better? I'm looking for boxes that are 16" wide x 12 - 16" deep by 4" high and where I can have front and rear panels milled by FPE

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…

After a few weeks burn-in period of this little beast, I found it's very relaxing to listen to. I can hear more juices coming out and the STAX 009 just doesn't have that analytical sounding cliché to my ears. It also enhances the soundstage and life-like of Focal Utopia makes it way more enjoyable to hear. This is a push-pull design tube Headphone Amplifier/Preamplifier attempting to achieve the true high-performance of headphones from Dynamic, Planar Magnetic to Electrostatic models. I've gotten a few PM's asking about the schematics and stuff so I decided to open a thread to discuss more here. …

I've building a preamplifier that also functions as a headphone amplifier. When no headphones are present, the gain of the internal opamps should be 1x (unity), so that the signal can be passed out the back of the device at line level for a speaker amplifier to further process. When headphones are inserted, the rear outputs disable, and the user should be able to select from no gain (1x), low gain (2x) or high gain (6x) to suit the impedance of the headphones. The entire operation will be controlled from an Arduino. I'm using a switched headphone jack to determine when a set of headphones has been plugged in. The gain should be selectable usi…

Who know headphones that van been transfered to 3M Peltor Optime 105 H10A/III H540A earmuff, without soldering or using soldering glue. To create ultimate sound isolating headphones. Noticed that Urban Ears Plattan version 1 can been used for this. But i search for another headphone that can been used, without removing wires from drivers.

Question regarding Diptrace. I decided to try this because I was laying out a board that was way outside of Eagle's capabilities (free version). This is a vertical backplane board housing 6 pairs of XLRs and 6 pairs of RCAs, some relays, etc. Do you guys trust the autorouter? I manually placed the jacks on 1: x and 1.5: y grid, and locked them. I then manually placed the relays in the best spot (I think), locked them, then let it place the rest of the components. I adjusted some net trace widths, but let it autoroute. Seemed OK once I did a few tweaks to it, but just wanted to get some input, as I normally wouldn't trust an autorouter in a non-commercial package.

Power is obviously higher than dynalo mk2，but But the temperature is high too.

so pars posted this. http://www.diyaudio.com/forums/group-buys/315474-pure-tube-es9038pro-9028-9018-akm.html#post5259820 all sorts of wrong. lets start with the fact that current output D/A converters really like driving a zero impedance. 27 ohms is not a zero impedance. So with +/-1.2ma you get +/-32mv and then you use the tube to amplify the crap out of it. Nope, definitely not the way to do this. All sorts of noise etc... a while back there was bakoon and audio-gd pointing fingers at each other as to who designed satri and when. so here is the satri version 4 circuit satriic.PDF and here is how audio-gd turns it into both the I/v converter…

I'm going to create a thread for this amp since it is my intention at the end of the build to publish the schematic and any relevant details so that anyone who's crazy enough can build this amp. So for now this (and the amp) are a work in progress and just somewhere where I can share pictures. Actual information will come later. Night #0 of PS chassis fabrication: I did a preliminary layout of all of the parts on a large 17" x 14" x 4" Hammond Steel chassis that I happened to have laying around. It seemed big enough so I took rough measurements of where everything was located so that I could tweak them later for better alignment and symmetry. I'm not all that concerne…

As somewhat of a learning experience, I decided to build a PSU using the kgbhultraminipsV4 board (KGBH). All seemed to go well in assembly, and I tested every adjacent solder point for proper continuity, and ensured no cold solder joints. Used proper heat sinks on the silicon devices wires while soldering to avoid overheating them. Cleaned the board with 99.99 alcohol. I set the board up with 2x100v and 1xs150V zeners to output 350V. I plugged it into a 300V x2 transformer (smartly using a very long extension cord in the garage) it I got a HUGE pop. I was using 5W zeners, and when they go, they really go! It was the Positive side of the PSU. One zener totally evap…

I want to experiment with making some data only USB cables. Looking at the specs of the bulk USB cable by lcomm it shows 28awg twisted for the data lines. Is it ok to use stranded?

I thought it would be fun to document the insane amount of work it will take to turn the Single Power ES-2 into something useful. Now Kevin had done quite a bit of work for me such as fitted new teflon tube sockets and teflon Stax sockets but that still leaves a lot of shit to do. Here is what it looked like when I got it: The wooden front for the amp section was cracked so Kevin threw it out. The weight of just the empty chassis was pushing 24kg so my first decision was to ditch the PSU and do it internally. First up do the back panel: Here is the reason why I don't add RCA's to my amps... Now for the front panel. Mikhail had plenty of …

only talking about non-ESD amps here (aka common amps), if the amp has no negative feedback, (using n-fb could achieve pretty pretty low output z, 0.0x ohm i assume), but how about those none-fb ones? open loop is a hard subject