Test carefully using an oscilloscope (in DC coupled mode) so to watch the preamp's output settling. It will take it some integration time to follow an input offset once suddenly introduced. That may bring a bump. Even worse if its beyond what it can handle it will stick high up towards the rail. It takes responsibility to operate such a system if there is no capacitor coupling towards the amp. Else a power up sequence mistake with the source on last or some dac chip mode that does offset beyond what it can be corrected and bye bye speakers / headphones.
No oscolloscope availiable, unfortunately. I' m thinking to use coupling capacitors for start and do basic measurments with DMM. I' ll try to remove capacitors on a "guinea pig" system and when I get stable behaviour move to no capacitors setup. Amps are also tubed with differential input. I noticed improvement with regards to switch on/off bump handling in comparison with the previous SE version of the same amps. I hope this will help.
Hi... Have you seen the .pdf file i uploaded in post #303 ?
I can confirm, that after testing them in that setup, PSU is working as supposed.
Jesper.
Just use about same idss ones around the 5mA mark but with 1R instead of 33R source resistors.
Thanks Salas. Also with the small value capacitors ie 10 pf and 33pf, would 16pf and 36pf be suffice without any issues?.
Quan
Hey.
I sourced mine NEC's cheap from ebay!
I wouldent bother trying out 2sk170, when the NEC parts are so easy to get.
But ofcause if you want to try if there is sonic difference, it's ofcause another story.
Jesper.
Well, no longer cheap... prices nearly doubled. Wonder why?
Siberia, If I were in your shoes, I'll keep precious Nch and Pch JFet for other projects.
TESTrig complete
Good evening all!
First off... Sry. for my "school" English!
So finally, i had good time to really listen to this brave pre. made by Salas.
Story is, i decided long ago (or my wife actually did), that we needed a headamp. Thing is, she really likes listening really loud in her headphones.. but normally she uses her pc, which cannot play them very loud
My Pre. right now is a B1 buffer unity gain, and to be honest i also think i need a little gain for driving my F5's (right now taken apart through)... So Salas presented a new construction with buildin headamp. -I took the challange and designed my own pcbs (looking at Salas design). Everybody here was kind enough to chime in and help! thanks all for that.
Yesterday Friday, i had a day off, after we was at concert Thursday evening (more about that later) I soldered my second DCSTB, for trying dual psu.
-Also i have recieved my pidac, so everything was ready to hook up now.
Whoow... man, this thing really rocks... channel seperation is in particular good, but soundstage also rock's (by soundstage i mean the area behind and in front of speaker's)... Right now we are listning to a new, very good upcomming Danish band. (See link below)... It was also that band, we saw Thursday evening... really good live. -That voice of this young fellow, is as good live, as it is on recordings, not something you hear every year i think.
I wish you all a good Saturday evening!
Best Regards; Jesper.
Attached some pictures of my testrig, happy wife etc...
Scarlet Pleasure :
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwi419yAzqPQAhWCUBoKHUJTDnIQFggaMAA&url=https%3A%2F%2Fwww.facebook.com%2Fscarletpleasure%2F&usg=AFQjCNHnZVcvJfV4VTWs4oqKVTLU_4yEpg&sig2=iAYEyXF7LoAB2wVfyD7jGA
Good evening all!First off... Sry. for my "school" English!
So finally, i had good time to really listen to this brave pre. made by Salas.
Story is, i decided long ago (or my wife actually did
), that we needed a headamp. Thing is, she really likes listening really loud in her headphones.. but normally she uses her pc, which cannot play them very loud My Pre. right now is a B1 buffer unity gain, and to be honest i also think i need a little gain for driving my F5's (right now taken apart through)... So Salas presented a new construction with buildin headamp. -I took the challange and designed my own pcbs (looking at Salas design). Everybody here was kind enough to chime in and help! thanks all for that.
Yesterday Friday, i had a day off, after we was at concert Thursday evening (more about that later) I soldered my second DCSTB, for trying dual psu.
-Also i have recieved my pidac, so everything was ready to hook up now.
Whoow... man, this thing really rocks... channel seperation is in particular good, but soundstage also rock's (by soundstage i mean the area behind and in front of speaker's)... Right now we are listning to a new, very good upcomming Danish band. (See link below)... It was also that band, we saw Thursday evening... really good live. -That voice of this young fellow, is as good live, as it is on recordings, not something you hear every year i think.
I wish you all a good Saturday evening!
Best Regards; Jesper.
Attached some pictures of my testrig, happy wife etc...
Scarlet Pleasure :
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwi419yAzqPQAhWCUBoKHUJTDnIQFggaMAA&url=https%3A%2F%2Fwww.facebook.com%2Fscarletpleasure%2F&usg=AFQjCNHnZVcvJfV4VTWs4oqKVTLU_4yEpg&sig2=iAYEyXF7LoAB2wVfyD7jGA
Attachments
Only some old Philip's ones we bought on sale some years ago. They where very cheap around 12-12Eur or so
Actually i am thinking of buying some better ones for christmas, but it's a new world for me, so i had to do some research first. -Maybee pricerange around 75Eur maybee 100Eur... Not decided yet.
Jesper.