thanks peter, but that is not the note. this one describes a amplifier setup for speakers. i could have sworn there was one diagram somewhere which specifically stated "headphone amplifier" anyway, it doesnt matter, i have plenty of other well documented headphone amps to build yet!

digi, do you have a schematic for the headamp that you can post? i think i once saw a BB/TI pdf that talked about using the OPA548 in a headamp, but i cant find that file any more. i too like your ground plane. very pretty... very big. i think i would like to try using a larger ground...

frosty, you definitely described my MO. another point is i dont spend my life thinking about headphones.... i like to spend as much time as possible listening to them (even though i dont have great gear/cans) radrd... asparagus.. yum... krayzie, i believe they were in the 170USD range...

radrd, i hope i didnt sound too sarcastic. just joking around. thanks for the compliment. re: the earphones, i see them in shops here all the time. i too am tempted... but not enough to reach for my wallet.

yeah, but am i right?! edit: i count about 6 threads, including one with "cumulative reviews" culled with various sources. btw, what does posting alot mean? you know alot? you like typing....

julian, do a search in the DIY and headphone forums. there are quite a few members who live in HK, buy crazy headphone and amp stuff and make their own. HK is gadget city and DIY heaven. try going to ap liu street in sham shui po (MTR exits A and C) there are tons of places to buy tube and IC...

do a search. you'll get some hits.

terrymx: "but dont bother, its like asking how the ath-fc7 sound." too true terry, sound is pretty subjective... and personal. a wise man on this board once said something to the effect that there is no such thing as a good cheap closed phone. i recently bought the ath-fc7 for 45...

do a search on this topic. there seem to be lots of people making or wanting to make these things, including a few who are working on PCB's. mabye they will be willing to do a larger run on the PCB's...

hate to say it, but you are right, it is kind of a stupid question. the TLE2426 is a rail splitter. used to give you the +/- voltages which power the opamp. it is used in the power section of the amp. if you look at the pimeta schematics, there is an opamp in the ground channel, (just like...

just got a pair of the ATH- FC7 for 350HKD in sham shui po. the FC5 was slightly less expensive. they seem like a decent, portable set of cans. i havent let them burn in or done a real in depth comparison, but i think i like my sony D-77's better.

dan, i had a similar desire to see the innards (i think they look cool) and light them with LEDs. i am looking around for a lucite box for my amp (non-portable)... or will get one custom made. of course i'm in HK where they have little shops that will do that kind of stuff....

TMC, i dont think you will find etys or shures cheap in HK. in fact, i dont think they are popular here at all. HK has lots of stuff from asia, particularly japan. its not always cheap, but at least you can get it here. if i am not mistaken, etys and shures are US made/brands, and therefore...

i got the transformer from a large wall wart. i found it around the house and dont know what it was used for, it was rated at 20V. the case said it was made in italy and has a nice diode bridge as well as what looks like a thermal resistor on the AC side.

i just got back into diy after a year's break. i decided to start with a new psu. 240V in 3-22VDC out. its got two sets of outputs. the one on the right uses a 12 throw switch to choose preset voltages (i know, i havent put any markings on the front panel yet). the other side uses a 10 turn 5k...

here is a link to a tube audio site in HK. http://www.hktubeaudio.homestead.com/index2.html if you go to link at the bottom, tube shops in HK, there are maps to a few areas. the mong kok building is where i saw some headphones (obviously not in the tube shops) the Apliu st map shows...

definitely check out lojay's links. esp the chinese map. they show the best places to go for toys. there are a many of stores in the yau shing plaza just outside exit E2 - bank centre exit of mong kok, mtr. i think the one on the 7th floor carries some headphones. there is an undergroung...

check out this page: http://hktubeaudio.homestead.com/ click on the main menu, then the page for tube shops in HK. this lists popular DIY shops in HK and it is pretty comprehensive. Ap Liu St is definitely a must, but alot of the shops/stalls there sell parts for "industrial" use and may...

the 77's are good, but i dont think they are great or worth the money you were quoting. i got a pair from a friend a few years back. they were my only pair of "nice" headphones until i recently got the philips HP890. the 890 has much better... everything, but are not portable. the 77's are...

if you have some 337/317 lying around, you could build a PSU with a pot and adjust the +/- voltage supply on the fly. i have not built a dc coupled version, but i am surprised that if +/-5V didnt work for you, that your rack mounted +/-6V sounded great. is your transformer rated to give more...

everything i have read on the forums say that switching power supplies are no good. also, the output connector is an 8 pin connector. i guess for +/- 12V you would need only 3 of those pins, do you have a multimeter to figure out which ones? to use with a home amp, you would need a similar...

joe, i am using a cheap regulated supply from "platronics" on ap liu st. it is about 120HKD and puts out 13.8V regulated 3A. the brand is called "zurich" i dont think they have a 24v version, though. i am using it to power my szekeres. i hear no noise when no signal is going into the amp...

there are lots of PSU schematics on headwise. depends on the project you need it for. for opamp head amps, most need +/- voltage. for tubes and mosfet amps, you just need + voltage. if you are looking to regulate your 24V 1A PSU, make sure it is rated to output that first. then you will...

you need jumpers, otherwise no signal will feed into the second opamp stage. L and R of S2 switch out should go to L1 and R1 respectively

i saw this amp branded "sound master". some guys here ended up ordering the "radii" one, maybe they will post review soon?