Do It Yourself

Well its not like the stax mafia aren't busy and we certainly are not going to do an output stage with 8ma of current, and therefore no reason for a 4 stage amp, and since tube inputs seem to be the big thing lately, well might as well take the kgsshv-carbon design and replace the input fet with an input triode. bonus, no low voltage supplies. not a bonus, ksa1156 and ksc5026 run at close to 1 watt each. I should have a real t8000 end of june, but this should keep some of you busy. I expect joamat to have one built in less than 24 hours. no, no circuit board yet about 70 volts on the plate of the tube, same as t2. optical servo from kgsshv-carbon…

Anyone ever tried them? If so, what setup worked best and how quiet were they? I've been thinking up logistics of the SRM212 I'm recasing with the new HV power supply. Thinking about using a small 40mm fan since the heatsinks I will be attempting to use (same ones as what I'm attempting to put in the mini Dynalo) aren't that big and I want to crank it to 10mA. I'll be using one per channel so 2 total and each will be dissipating around 11-12W. Guesstimating 4C/W rise on the sinks (no specs stated in the listing) that's around 75-80C on its own If it's 5C/W then it's really bad times.

Thought it might make sense to make a new thread on this so as not to pollute the T2 thread. So this would be limited to the chassis, any potential board run, and any other potential group buys for traffos or transistors (if numbers warrant). I am hoping to move forward by the end of the week. Please keep in mind, if you are in and make your deposit, you are committed and will not back out unless you find someone to take your spot (so if you are not well established, then paypal gift only). Please express interest here or by PM. I have also included a link to the results of the first group buy:

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!

Hasy anyone used the silver plated copper wire from navships on ebay? I just picked up 10 ft of shielded 3 conductor 24 AWG stranded SPC. I'm going to use it as hookup wire and maybe balanced interconnects. Has anyone had any experiences with it?

Here are my BOM for a pair of BH. https://www.mouser.tw/ProjectManager/ProjectDetail.aspx?AccessID=b44788bc7f for GRLV and GRHV. copied from Carbon build thread. http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=b6d687c7f7 http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=54687aa8fa Parts I already have or going to buy from local dealer are NOT included like LEDs, insulators, IC sockets. Someone need to check if all resistor value are correct. I hope I could finish it at the end of April

I purchased this DAC from another HC'er in Canada down to the states but it looks like maybe he didn't get around to testing it out before selling it to me as it locks onto digital signals but provides no useful output otherwise. I only have a glimpse of the history of this thing but it's lived a rough life. I am positive old forum favorite NoNoNoNoNoNo is the previous previous owner and the work here is very very bad. Lots of WTF and cold solder joints everywhere and bonus scorch marks on some box caps, that odd white wire is a jumper used after he lifted a pcb trace... As a novice I have since cleaned this thing up as far as I can get it, at least at my skil…

http://www.ebay.com/itm/322416989057?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT Looks real in the pic and has a pic of a lockyz output from the curve tracer. Gets good feedback and all. Still no real way for me to tell from the pics. I was hoping to buy a set and ask one of you more experienced users to test them for me to see if they meet original specs.

http://korgnutube.com/en/ SMD tube?

I have some Grado Aluminum headset blocks that I got from the guy in Malaysia. I've been trying to find someone who will do a small job like this but have been unsuccessful so far. I would like to get R and L milled into them with the square border areound the letters like on the Factory plastic blocks. Anybody have any suggestion for someone who would do something like this?

So I am planning on ordering a bunch of the BC546 and BC556 for the Unbalanced\Balanced board and I'll need to measure, sort, label and store them. 1. can I store them in a regular plastic parts bin with dividers? 2. can I stick labels on the pins and fold the labels closed?

I and a few others have decided to get the new bipolar version of Blue Hawaii PCB made by PCBnet in US. I used PCBnet for the Carbon GB in 2015 (and other occasions). Their price is higher but we’ve had great experience with their board quality. The boards will be 2mm thick and 4oz copper, green solder mask and white silkscreen in leaded finish. The cost of boards is $30 USD for a set (two PCBs) if we can get 15 sets made. You’ll need to add shipping from me to you for the total cost. Kevin released this latest version of Blue Hawaii in early 2016. I worked with Kevin to trace the board and at least one headcaser has built one working amp with them. This …

In Netherland there's not much people interested in headphones, but thank god, I've found three persons in my building and I successfully persuaded them to build the 8 EML tubes fully dc coupled DHT amp. They're speaker guys, anyway since their children are too young and the wives want to keep the family quiet, they agreed to try headphones. We will do it toghter, one person alone couldn't afford it. We want to build it, yes, 120% sure

I was going to build a balanced isolation transformer. But I had difficult to choose form either EI or toroid. Regardless of price and size, which theoretically will be better (in performance)? I was planning to build around 2KVA. Does anyone have experience?

Does anyone here have experience with the SEN I/V stage? I want to try this with my BIII http://www.diyaudio.com/forums/digital-source/195483-zen-cen-sen-evolution-minimalistic-iv-converter.html

Hello All... Since there were a bunch of requests for more GRLV boards I'll do another round. I've also added the boards listed below that are in demand. Also, as a side note if you're looking for boards from my last GB I have one set of Dynahi boards, four or five Dynalo Mini, and a few volume pot boards left. Send me a message if you need any of those. Sign up Sheet: https://docs.google.com/spreadsheets/d/1Z1L3MQuuY4ZTUyPQb1qBmVJp8MtC7qEzBUui3z5dFrQ/edit?usp=sharing Balanced\Unbalanced board (both smt and through hole) Through Hole http://gilmore.chem.northwestern.edu/boards/diffinput3.zip SMT http://gilmore.chem.northwestern.edu/boar…

I was thinking about slapping this together on a breadboard: https://www.fairchildsemi.com/application-notes/AN/AN-6610.pdf The transistors listed (92PU01 / 92PU51) must be ancient as I cannot find them. I ran across somewhat of a datasheet here: http://www.datasheets360.com/part/detail/92pu01/3582415256795608549/?alternatePartManufacturerId=0 It looks like a Fairchild KSD882Y might come close? Or could I use anything capable of a bit of power (such as MPSW06/56)? It would seem that an Ic of 2A on the 92PU01 is pretty high for what might be required here?

so sorenb really wanted this, so here it is http://gilmore.chem.northwestern.edu/cfaelectrostat.pdf the outputs are 300v darlington transistors just need to find a suitable npn match for the stn9360, and this can be done all surface mount tiny, fully complementary, fully dc coupled, decent input impedance (none of this 75 ohm nonsense) push pull output... edit: PBHV2160ZX looks great for the npn. so you can add one more set of outputs and run up to 500v power supplies balanced input only, and you need 4 of them

Some guys insist MUSES 72320 is better than relay-based vol control, but I highly doubt that. Any tried that? (Let's ignore those CS3310 etc which are not so good, we only talk about that 72320)

Just grabbed a pair of 207, almost new, cost $400... Gonna wanna diy an amp for it, better under $3,000... is kgss seriously overkill? Just wanna have a taste at the famous stax, no interested in the superior models, yet.

Kevin says Collins radio potentiometer is pretty dawn good, could anyone provide a little more details about Collins radio？ http://www.head-fi.org/t/677809/the-stax-thread-iii/2895#post_10778293

Recently a distant friend grabbed a few of this pot, called bi p260p, made by plastic，sounds like some common Brit stuff. seems nothing special at all. But lol, I gotta lol first, P&G is OEM by this company... Actually, P&G is the cherry-picked version of this pot, the tolerance of this pot is 10% (means channel unbalance), we could just pick 10 of these, and select them by ourselves. No need to pay the price of P&G. btw, made by plastic is actually the element is plastic. link http://www.bitechnologies.com/products/panel_pots_sg.htm http://www.bitechnologies.com/ProAudio/ProAudio/index.htm

Is there a balanced to unbalanced (single ended) board that is recommended? Twisted Pear has two options but they use op amps, and then there's the Broskie Cathode Follower, and Unbalancer Two. Those two use tubes. What else is out there?

Edit: Group buy on Song Huei pots is closed. Please see the this post for the current TKD group buy The latest version of the Dynalo SS Mini board uses a 21 mm alpha potentiometer. Song Huei potentiometers are identical in every way and and inquiry with them has led to the possibility of a small order limited to ~100 potentiometers. Otherwise we would need a minimum order of 1000. Due to the low number of available potentiometers, whoever is ordering a Dynalo Mini SS PCB will get first priority and extra potentiometers will be limited. Due to the reported failure rate of these potentiometers, I will also accept returns to send back to Song Huei in order to get…

How can I measure if my DAC puts out common mode DC from the balanced outputs?