headphone amplifier

[awpagan]

awpagan - thanks for info....which headphones do you have ??

I'm using Beyerdynamics DT880's

allan

 

[sparkle]

awpagan - thanks

Per-Anders - thanks - this is a new one for me - i will consider it - nice design btw....it seems to me that i can't download the pdf file of the project.....

EUVL - thanks for the link...really nice, easy and it seems to work very very nice....the only problem is that i do not have LU1014 and i can't find/buy them.....is there any other substitute that i can use like other fet's....what would you recomend ?
also - those 2sk1529 could be substituted with irf240 - in that case is there a sweet spot determined for the fet...what should be changed....?!



regards to all

 

[EUVL]

> the only problem is that i do not have LU1014 and i can't find/buy them

You could try asking Steen or others for just 4 pieces, as most people are ordering 20's and have spare.

Or you could use 10 pcs of 2SK170V (matched) to substitute one LU1014.

I would try asking in the group buy thread first. Also I think someone in Europe used to sell them. Maybe he still have 4 for you :

http://www.diyaudio.com/forums/showthread.php?postid=1092673#post1092673


Patrick

 

[sparkle]

it is to much complicated for me and to much costly....because i have to pay aditional costs to the government etc......not good...that is why i did not want to try those projects from Mr. Pass..... a problem to find them........

it is a pitty that those parts are not available a bit better......
it seems that i have to leave this project for better days...
anyway - thanks for trying ...nice project......
many regards
daniel

 

[diy2000]

I'm fairly enamoured with Per-Anders QRV06, which is based on a diamond buffer, with current feedback.

It's a well thought out design, really fast, with very low distortion.

I'm thinking that with high impedence headphones you might want to run at higher than +/-15V in order to put decent power into them (especially if their sensitivity is relatively low). +/-20 or even +/-30V is probably more appropriate. Of course that rules out many op-amp based implementations, as these tend to be limited to +/-15V.

This is the one i recommended to np and he knocked it back in favor of the aleph-muni,
I think zenmod is a bit inexperienced in very tiny amps and spks ,here we need to conserve pwr so a very good class-b with low dist. is what would be ideal

 

[Zen Mod]

This is the one i recommended to np and he knocked it back in favor of the aleph-muni,
I think zenmod is a bit inexperienced in very tiny amps and spks ,here we need to conserve pwr so a very good class-b with low dist. is what would be ideal

hehe

it's hard to beat my 0,6W SET hen you talk about timy amps

that's my regular amp for listening on headphones ....... even if they ,in fact, sorta giant ones ..............

 

[Zen Mod]

it is to much complicated for me and to much costly....because i have to pay aditional costs to the government etc......not good...that is why i did not want to try those projects from Mr. Pass..... a problem to find them........

it is a pitty that those parts are not available a bit better......
it seems that i have to leave this project for better days...
anyway - thanks for trying ...nice project......
many regards
daniel

don't take me wrong - I don't wanna advertise where is not place for that ....... but - if you are interested in Babelfish for headphones, I can help you with that , without need for paying customs or whatever .... I can sell you Babelfish package and send it to you via my relatives in Croatia ;

or - if you are willing to make it PtP , then your only problem is finding jfets locally ; I think that Elmatis in Zagreb still have 2SJ74BL, perfectly good as substitute for 2SJ109BL (two matched 74s for one 109) ;
I can draw exact schematic of Babelfish thingie for headphones and post it here ; you can make it for pocket money , if you are willing to think a little ;

 

[diy2000]

hehe

it's hard to beat my 0,6W SET hen you talk about timy amps

that's my regular amp for listening on headphones ....... even if they ,in fact, sorta giant ones ..............

hahaha ,losing ur religion i see (clas-alpha)

 

[sparkle]

diy2000 - thanks for info....i think i will go on something like dinahi design first and then see how it is working - something like that ....probably i will change the gain ot the amp right away to have gain arround 6.....
http://www.djgardner.com/headphone/gilmore/dynahi/schematics/dynahi2.gif

zen-mod - yes, i think that i can find 2sj109 and 2sk389 in elmatis ....they have it in their catalogue so i have to call them today to check if they really have it.....also 2sc3381 and 2sa1349 is in their catalogue too....so i will have all the problematic and criticall parts....
it is not a problem to think....or to develop an amplifier and the board....what i needed here is an information what to look for when having 300ohm headphones that are not very sensitive....what type of the design will work the best on them .... of course there are many variations.....
since i can find those nice fets (389 and 109) and since i want to try to do something with them for a long time i am pretty interested to start something with them
so probably dinahi type of the desing will be the thing to start with - at least the input part with the dc offset adjustment (maybe better some variation of it)
thanks to every effort you made here in this thread

 

[sparkle]

i have just checked - 2sc3381 and pnp pair of it are expensive as a hell....
can anyone suggest something that is not costing 10USD or similar per piece....other than pairing single bjt's ....


also 2sk389 and 2sj109 are out of the stock in elmatis - they hope that they will find them and have them soon.....
man!

BC550/560 are the best.......

 

[jacco vermeulen]

expensive as a hell

Depends,Beep

For an affordable parts circuit, you could ask PPL for a folded cascode update of THIS

 

[sparkle]

thanks Jacco,

this link is very valuable.....nice....the only problem with it is that the guys accept money bank transfer which is very expensive here in my country....but - maybe i could organize a bigger order - so that this money bank transfer would be less problematic to pay....
i will see.....

this folded cascode is very interesting....it is something i wanted to create - very interesting indeed....some of the ccs's can be made without J-fet's (using only bjt's)...

i have at my home 4pieces of 2sk389 that i can use in the input....also i can find BF245C that are cheap here that i can use also....for some current sources.....at the end (i am affraid) it will look like monster ....


btw. i can't find the thread about CCS2 design.....is it on diyaudio??