Zen Mod Napisano Mart 22, 2012 Autor Share #1057 Napisano Mart 22, 2012 anyway - be happy - input Jfets are still pentode-like ........ so nothing wrong with proper pentode even in output :roflyou remember - M2 isn't so bad amp , even with plain Mosfets in source follower configuration Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Mart 22, 2012 Share #1058 Napisano Mart 22, 2012 O.K. thank you both for your explanations and hints.......! :)and I am afraid my cd-player is also pentode like so I have no chance......... :Pmaybe one point is important, the Mufollower is normally more push pull than single ended..... Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Mart 22, 2012 Autor Share #1059 Napisano Mart 22, 2012 Gyou don't need these two 0R68 resitorsjust bridge them ( short) and re-set Iq and offsetthat way you'll have even less Mu Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Mart 22, 2012 Share #1060 Napisano Mart 22, 2012 Gyou don't need these two 0R68 resitorsjust bridge them ( short) and re-set Iq and offsetthat way you'll have even less Mu every suggestion welcomeI will try and hear.... Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Mart 22, 2012 Autor Share #1061 Napisano Mart 22, 2012 as always - you're more than welcome Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Mart 23, 2012 Share #1062 Napisano Mart 23, 2012 as always - you're more than welcome Gyou don't need these two 0R68 resitorsjust bridge them ( short) and re-set Iq and offsetthat way you'll have even less Mu o.k. I bridged the 0R68 resistors and ....now in my system the sound gets even more precise but a bit too hard and less "panoramique"so I returned to the former constellation..incredible what o.34 Ohm changes.......!next tries come...... Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Mart 23, 2012 Autor Share #1063 Napisano Mart 23, 2012 Link to comment Podeli na ovim sajtovima More sharing options...
ozzy Napisano April 27, 2012 Share #1064 Napisano April 27, 2012 10mm za MF (15mm za R32)23mm za 3Wto su sve dimenzije direktno iz lib , s tim sto sam maltene sve korigovao velicinu padspcb je 80x110Od Tea-bega kupio Semisouth-e ,hvala na podrsciZoran Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano April 27, 2012 Autor Share #1065 Napisano April 27, 2012 sluzimo narodu ! Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 4, 2012 Share #1066 Napisano Jul 4, 2012 update for all BJ2 fans and builders.... I occupied over 6 weeks with the sound of my BJ2 compared to an original FW J2........ it was a hard time...... I tried all.........................................................................................! I even ordered a pair of R125 because the FW J2 had them, from a guy at Miami, but, no the input was the place! To make it very short............................ to come near to 80% of the lovely sound of J2 original....... I had to take one pair of 2SJ109 in the input. ( I know it is a compromise) Every try to set in, even very closely matched quadrupels of J74, and not so closely matched two 2SJ109 in parallel, (I spend some money to buy them in Germany and I had to sent back some because they were sold defect.....) ................gave a more muddy sound. So if you want to experiment with your BJ2 and you still have a pair of good old 2SJ109 give it a try. After six weeks it is a happy day today! Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Jul 4, 2012 Autor Share #1067 Napisano Jul 4, 2012 :cheers: Link to comment Podeli na ovim sajtovima More sharing options...
Mikorist Napisano Jul 4, 2012 Share #1068 Napisano Jul 4, 2012 Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 4, 2012 Share #1069 Napisano Jul 4, 2012 :cheers: I wish you could hear it! Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 7, 2012 Share #1070 Napisano Jul 7, 2012 Just for fun I changed today the one 2SJ109 BL in the BJ2 to a pair of closely matched 9610. (from diytech 0,01V), Zm will laugh, "change your lousy BJ2 back to an Aleph 3"My intention was to drive them with the 20mA the two 2SJ109 or four J74 get normally, and I was eager to hear if the much higher transconductance would do something to the sound.sound is (as often remarked) darker, a bit more punch in the lower bass, but much, much less detailed and airy than the J-Jfets.So back to one 2SJ109 per channel again.....Can anybody comment if going to 15mA with one 2SJ109 device would be to much, Euvl did even heatsinking the 2SJ109 in former times when they were still more in use.... Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Jul 7, 2012 Autor Share #1071 Napisano Jul 7, 2012 Babelfish J2 or "origigi" J2 schematic ?by 15mA you mean setting CCS in tail to 15mA , so 7,5mA per side ? Link to comment Podeli na ovim sajtovima More sharing options...
Sipi Napisano Jul 7, 2012 Share #1072 Napisano Jul 7, 2012 ....Can anybody comment if going to 15mA with one 2SJ109 device would be to much...Depends on Idss of each JFET inside j109. If you set the Id higher than Idss you'll put JFET in dangerous zone where Ig starts to flow and JFET starts to act differently. Don't go over 90% of Idss - or your panorama will be lost, and JFETs will follow.... Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 7, 2012 Share #1073 Napisano Jul 7, 2012 Babelfish J2 or "origigi" J2 schematic ?by 15mA you mean setting CCS in tail to 15mA , so 7,5mA per side ?yes 7,5mA per side.....and I confess "origigi" Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 7, 2012 Share #1074 Napisano Jul 7, 2012 Depends on Idss of each JFET inside j109. If you set the Id higher than Idss you'll put JFET in dangerous zone where Ig starts to flow and JFET starts to act differently. Don't go over 90% of Idss - or your panorama will be lost, and JFETs will follow.... thanks Sipi for valuable hints.... and I take care of the panorama! :oke:and I will give the 2j313 a try instead of old 9610 Link to comment Podeli na ovim sajtovima More sharing options...
Zen Mod Napisano Jul 7, 2012 Autor Share #1075 Napisano Jul 7, 2012 yes 7,5mA per side.....and I confess "origigi"Sipi already tell yain case that you have some 2SJ109V , it will be possible , but non cascoded origigi is still nono , regarding dissipation in that caseyou can always use J271 ( matched ) , thinkin' about Idss and Vgs ratio , but dissipation is still issue even with themno free sonic lunchbe sure that you really hear as difference between your's and Pa's iterationI know what he would say ......... Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 7, 2012 Share #1076 Napisano Jul 7, 2012 Sipi already tell yain case that you have some 2SJ109V , it will be possible , but non cascoded origigi is still nono , regarding dissipation in that caseyou can always use J271 ( matched ) , thinkin' about Idss and Vgs ratio , but dissipation is still issue even with themno free sonic lunchbe sure that you really hear as difference between your's and Pa's iterationI know what he would say ......... Pa is of course in the sweet spot......me not....thanks Zen Mod Link to comment Podeli na ovim sajtovima More sharing options...
Sipi Napisano Jul 7, 2012 Share #1077 Napisano Jul 7, 2012 ... and I will give the 2j313 a try instead of old 9610 I doubt that it will be an upgrade at such a low current, but you can give it a try...If we were talking about 300-600mA than you would clearly hear the difference, but as input devices - Ich glaube nicht... Link to comment Podeli na ovim sajtovima More sharing options...
generg Napisano Jul 7, 2012 Share #1078 Napisano Jul 7, 2012 I doubt that it will be an upgrade at such a low current, but you can give it a try...If we were talking about 300-600mA than you would clearly hear the difference, but as input devices - Ich glaube nicht...Danke! Link to comment Podeli na ovim sajtovima More sharing options...
Preporučeni Komentari
Kreiraj nalog ili se prijavi da daš komentar
Potrebno je da budeš član DiyAudio.rs-a da bi ostavio komentar
Kreiraj nalog
Prijavite se za novi nalog na DiyAudio.rs zajednici. Jednostavno je!
Registruj novi nalogPrijavi se
Već imaš nalog? Prijavi se ovde
Prijavi se odmah