he is still on the bench the time to finish the test. for now he's still on suicide speakers, realistic minimus7. my diet is a little low in tension, and the bias is also a bit low but it is already working very well.
i have an old industrial power supply box from the 70' for him,it will fit him like a glove
it is a little bit clear with a real speaker (jm lab opal19) ... in fact, I had mounted with 6p6 Chinese because it does not matter if I burn them, but in any case, they are really bad (I had never listened before), I went to Russian 6p6s and it's already much better then I'm doing a test with tungsol and it's not bad also now I'll try in pentode mode then triode and also as suggested before, with 6sn7. it's a bit tricky for me, I do not know the floating paraphase well, but I'm going to learn
i have an old industrial power supply box from the 70' for him,it will fit him like a glove
it is a little bit clear with a real speaker (jm lab opal19) ... in fact, I had mounted with 6p6 Chinese because it does not matter if I burn them, but in any case, they are really bad (I had never listened before), I went to Russian 6p6s and it's already much better then I'm doing a test with tungsol and it's not bad also now I'll try in pentode mode then triode and also as suggested before, with 6sn7. it's a bit tricky for me, I do not know the floating paraphase well, but I'm going to learn
Attachments
I still have one of these boards sitting in my project bin- I cut some traces and modified the front end to a gain/concertina setup, and populated the board but have not yet completed it, as I don't have any suitable iron on hand. Using a 6N9S input tube for it. The plan is to go tetrode mode output. I have a dozen Russian 6P6S to dig through and use with it, lovely tubes
have you an schematic of gain/concertina stage ? because,i have try a pentode mode,it's better but a little too bright,too rock for me . so ,my reference is a harman a300 amplifier ,the king of cool and smooth attitude ,like "the Duke"
in fact,for now it makes me think of a transistor amp in class Ab, very fast and nervous, lacking a little coolitude
in fact,for now it makes me think of a transistor amp in class Ab, very fast and nervous, lacking a little coolitude
You'll need feedback with tetrode mode or else the output impedance will be high, as will distortion. Triode mode will work, but you *might* get some rolloff due to the miller capacitance of the 6v6 in this application. The 6N9S can't really drive difficult loads when used here, although the 6SN7/6N8S will do fine at reduced gain for triode.
Tetrode connection with feedback is truly ideal here.
Tetrode connection with feedback is truly ideal here.
ok,thank's. i used mine with preamp or buffer or cd player with variable output . best result with cd player in direct
if anyone know how to check the bias off the 6sl7 in floating paraphase ,i would like to know too
always for my learning ,if anyone can tell me why the original schematic have is modified and what is a consequence ?
I found some answers to my question but not all. Dynaco low Power Amp if someone wants to help me understand the changes from the original schema. I'm struggling a bit on the classic scheme but this one, I have trouble.
I think I'll stop there for this design. it works certainly, but does not give me satisfaction listening. I read a lot of topic here (I did not know that we had talked about it) and it convinced me that it was a catalog design not completed and ultra low cost ... I'm going to keep the map, cut the tracks and go on something more known and recognized.
or modify it to make an acrosound 6l6
So, as the subject had already been discussed a hundred times and nobody wanted to answer me, I continued to look and I ended up on a diagram Magnavox modified by Dave Gillespie and in the process, I ordered one of these pcb enhanced fixed bias to go with it. I started the modifications, I think that I will make it work in a first time in cathode bias to get an idea, then I will add the EFB thereafter. if it interests someone, I will continue to feed this thread, otherwise, I will continue on my side.
if anyone know how to check the bias off the 6sl7 in floating paraphase ,i would like to know too
always for my learning ,if anyone can tell me why the original schematic have is modified and what is a consequence ?
I found some answers to my question but not all. Dynaco low Power Amp if someone wants to help me understand the changes from the original schema. I'm struggling a bit on the classic scheme but this one, I have trouble.
I think I'll stop there for this design. it works certainly, but does not give me satisfaction listening. I read a lot of topic here (I did not know that we had talked about it) and it convinced me that it was a catalog design not completed and ultra low cost ... I'm going to keep the map, cut the tracks and go on something more known and recognized.
or modify it to make an acrosound 6l6
So, as the subject had already been discussed a hundred times and nobody wanted to answer me, I continued to look and I ended up on a diagram Magnavox modified by Dave Gillespie and in the process, I ordered one of these pcb enhanced fixed bias to go with it. I started the modifications, I think that I will make it work in a first time in cathode bias to get an idea, then I will add the EFB thereafter. if it interests someone, I will continue to feed this thread, otherwise, I will continue on my side.
What's wrong with this amplifier? you were happy on message #20 but don't anymore? 6V6 seem to have a quite strong reputation of "good sounding" tube, despite the fact that a tube is not supposed to have his own sound. I remember having read on a datasheet (radiotron?) that this type has been specifically made to generate very low 3rd distortion. I plan to build a low power 2PP 6P6S triode connected with only a 1:5 input transformer as a "driver". I made several simple amps like this with satisfactory results.
it works well, is very quiet, but very hard to listen, very brittle and brilliant, lack of bass. the voices are beautiful on the other hand. actually, when getting started on suicidal speakers, it was very acceptable, but as soon as I hooked it to TRUE speakers, that's when I realized that I did not like it. yet I am a fan of 6v6 and el84, I have several amps that are equipped and I know we can do much better with and that's what I will try to do. and finally, I recommend it as a learning kit, it is very good and without traps. I think like many people it's a "study and commercial" scheme to promote dynaco and acrosound output transformer. on the other hand, if you have dark and slow speakers, that's what you need.
it is also possible that the problem comes from my opt. I know very well the brand of these, but I do not know this model, I just know they were pulled from a French amp el84m pp, expected as 2x17w. on the other hand, it was done on specifications for the manufacturer of amp and do not appear in the catalog of the transformer manufacturer so I have no technical data. when at my hp, I can tell you that they go down very low with my other amps. and then we're here to learn so do it while having fun
So, as the subject had already been discussed a hundred times and nobody wanted to answer me, I continued to look ..... I will continue to feed this thread, otherwise, I will continue on my side.
I know it is lonely on DiyAudio sometimes, when no one seems to be interested and reply. However, I enjoyed your explorations. I have a Dyna SCA35 that I am rebuilding with Dave Gillespie’s boards, including EFB. I am eager to hear your observations of your new endeavor to compare conventional cathode feedback and Gillespies’s EFB.
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