kevin gilmore

srmxh, srm212,srm313, srm323 are all exactly the same thing with different current source transistors and different power supply voltages. not sure about the srm3 cavalli LL2T is a srm313 front end, the 007t output section with 6s4 as the gain section and a completely wasted pair of mosfets as the output stage. Takes more power to drive the mosfet output stage, than if the gain section was the output section. At least it sounds better than the frist two versions (so really it should be a LL3) which were pure shit. Wonder where alex got the idea to use 6s4? The only way to make a srm323 better would be to regulate the power supply voltages. Which is impossible in that size box. would need a different transformer and twice as many power supply caps plus some heatsinking for the pass transistors

the klone was done exactly as the original. Same exact board size. Each component in exactly the same place. Layout the same. Except done by computer, not tape and mylar. Why, because we can. if you want a klone of a klone buy the cheap pieces of shit on ebay. they made all sorts of awful modifications.

the grateful dead altamont system

i always like the belle klipsch better.

use the rear end of a drill bit the right size to open up the holes. some of those sockets are real garbage

not the spritzer i know. maybe you are thinking of someone else. the stax mafia uses discretes for everything. And yes we use opamps for servo's, but that is it. Even for the power supply its a discrete opamp.

that is because (among other reasons) birgir wants things to be as tiny as possible.

the lead spacing on the board for the .1uf cap is 3.5mm but the .1inch caps do fit. the 5pf caps are 5mm lead spacing by the way, I have a new name for the thing... PureBipolar (tm&c) would apply to the ss dynahi too.

i don't like those sockets, but otherwise ok.

parts list in progress so with the pot its about $300 in parts. need mounting screws, standoff's etc... item # $ 240 ohm 4 0.2 0.8 680 ohm 8 0.2 1.6 402 ohm 12 0.2 2.4 2.74k ohm 8 0.2 1.6 3.01k ohm 8 0.2 1.6 24.9k 4 0.2 0.8 5k 4 0.2 0.8 10k 6 0.2 1.2 49.9k 8 0.2 1.6 100k 4 0.2 0.8 20 ohm 32 0.2 6.4 14 pin ic socket 0.97 1uf 4 0 5pf 4 0 100uf 8 0 4.7uf 8 2.37 18.96 op07 4 1.56 6.24 that340 2 6.4 12.8 mpsw56 22 0.44 9.68 mpsw06 22 0.51 11.22 led 4 0 10k pot 6 0 haa15-.8-ag 63.63 boards 2 10 20 galaxy 288 69 rk27 quad neutrik chassis female 5 4.29 21.45 253.55

5 pin is the only way

not bad for a senior citizen http://gilmore.chem.northwestern.edu/dynalobalss.jpg I don't even do any metal work by hand anymore, even for the bottom panel which is just 8 holes, I do it in the NC mill and unlike Mikhail the holes end up in the right place the first time.

The only difference between the he60 and the he90 headphones is the stator material. the he60 uses fairly standard fr4, and the he90 uses some kind of plated glass. But otherwise identical in every way. Same size and shape stators, same diaphrams, same distances etc...

all the servo parts in exactly the same place hooking up to the same point. Should work fine. Any 1.7 or 1.8V LED will be fine.

kerry's multiamp boards are a bit different than the production boards.

sometimes mouser is out of stock on some caps, so I switch to in stock items. very little real difference between ceramic and mlcc

http://gilmore.chem.northwestern.edu/dynahibal4.zip in case you have not already found it

dynahibal4 was the last version with all Toshiba parts dynahibal5 has Motorola transistors and tosjiba jfets and Toshiba duals

back when I was in college, Yamaha was selling an integrated amp that had a class A switch on the front. In class A about 18 watts into 8 ohms. Otherwise 60 watts. filled with jfets. Would love to get my hands on one again in working condition. The tracking power supply thing has been done over and over. Not saying there is anything wrong with it, but it has to be done right otherwise it sounds like crap.

headinclouds has his kgst working now, I assume he will post pictures. had to decrease the cathode resistor to 1.1k and is running 10ma to the tubes.

here is the ubaltobal board with the fets http://gilmore.chem.northwestern.edu/dsc_0597.jpg you can do the same thing with the fets to the multiamp and then you can have a higher input impedance and you can do the same thing to the ss dynahi. Now that the fets are available thru diyaudio in small quantities, this is an option again. the boards are 5.47 x 3.02 inches to get it much smaller everything would (and could be) surface mount but the multiamp does do about 3 watts pure class A and the output transistors dissipate a total of 4 watts, so if smt they would have to be heatsinked I tested turnon/turnoff thump and there just is not any

there is a picture of the ubaltobal board with the jfets. will post board size later

edit: all of my chips are ti made A versions work fine

There are a number of parts to the complete preamp/everything solution. One is this http://gilmore.chem.northwestern.edu/baseboardbal3.jpg (low res for now) Which is the balanced input switch board. For unbalanced you use the neutrik rca to xlr converters. Next is the unbalanced/balanced to balanced converter http://gilmore.chem.northwestern.edu/ubaltobal2.jpg although there is a new rev of this board. you build it with the jfets because the that340 has significant bias currents. Now here is the thing about this part, its completely NO feedback ultra low distortion (<.001%) extremely fast, and gain is controllable by one resistor. (very similar to ayre kx-r only lower distortion and otherwise better) Next is the smt step attenuator http://gilmore.chem.northwestern.edu/attenuator5.jpg 256 steps, .5 db per step, two for balanced which includes a balance control http://gilmore.chem.northwestern.edu/ssdynalobal.jpg Finally is the multiamp as the output board, and also unbal/bal headphone board All the pieces put together comprise a seriously kickass preamp/headphone thing. Verified recently with amb/linuxworks lcduino and standard code. i made a change in the input board to get this to happen. But i really want a production version with touchscreen, and wifi so if anyone wants to step up and help... use any or all of the pieces seperately as needed its sweet i tell ya

The way the servo's is currently done results in +/-1.5mv of dc output. If what you want to do is the se to bal conversion you want the specifically designed thing i did instead of this. And build it with fets to keep a high impedance.