Someone who loves life 
I don't want to "poison" this thread, but, I've been contemplating my PASS UGS stages for the preamp and want to use only N-chn like you do here. Then the bright idea came - why not ask ZM if instead of using PASS stage, use and adapt your XA252 buffer stage With your blessing, this could uncomplicate things since I don't have to redesign in order to offer my preamplifier under a group buy if people end up wanting one.
What do you think ?
I don't want to "poison" this thread, but, I've been contemplating my PASS UGS stages for the preamp and want to use only N-chn like you do here. Then the bright idea came - why not ask ZM if instead of using PASS stage, use and adapt your XA252 buffer stage
With your blessing, this could uncomplicate things since I don't have to redesign in order to offer my preamplifier under a group buy if people end up wanting one.What do you think ?
if you continue as that, you're going to offer that preamplifier under the group buy somewhere in 2058
just curious, by which logic you call it "XA252 buffer stage"?
I mean, every decent made stage, with gain or not, is sorta having buffering function........ if made to have it; but some decently made stages, with gain or not, are not made to have buffer function .... but some other one
so, let's stay with old and boring nomenclature, where we with buffer usually mean "stage without voltage gain, having highish Rin and lowish Rout"
and - who do you think is going to make balanced stage of this ("Plethora of Pinjatas", as known in wakoo circles), when even I still didn't made it?
there is hidden work behind many funny schematics around, electronics sometimes isn't just shiny parts and kuglager-equipped volume buttons; meaning - helluva work to make it balanced, without too much complications and stage not wanting to kill your speakers every even time when you power it up
just curious, by which logic you call it "XA252 buffer stage"?
I mean, every decent made stage, with gain or not, is sorta having buffering function........ if made to have it; but some decently made stages, with gain or not, are not made to have buffer function .... but some other one
so, let's stay with old and boring nomenclature, where we with buffer usually mean "stage without voltage gain, having highish Rin and lowish Rout"
and - who do you think is going to make balanced stage of this ("Plethora of Pinjatas", as known in wakoo circles), when even I still didn't made it?
there is hidden work behind many funny schematics around, electronics sometimes isn't just shiny parts and kuglager-equipped volume buttons; meaning - helluva work to make it balanced, without too much complications and stage not wanting to kill your speakers every even time when you power it up
I guess I can correct myself and use your description, the [Input stage]. For me, the input stage is a buffer, buffering the incoming signal in case it is low, but if it is also a gain stage, I can call it a gain stage, no worries. Only preamplifiers need gain stage in my mind, but I am wrong, I can change.
When I look at the XA252 MOS schematic, there is a +IN and a -IN, but it is only BAL in and then converted to SE internally.
Meaning, I would need the XA252 US which is BAL internally also.
Looking at WAYNE'S BURNING AMP 2018 LINESTAGE, I see some similarity's in UGS and XA252 input stage and the offering in diya store is a balanced version, so you need two PCB's for stereo.
Am I correct ?
When I look at the XA252 MOS schematic, there is a +IN and a -IN, but it is only BAL in and then converted to SE internally.
Meaning, I would need the XA252 US which is BAL internally also.
Looking at WAYNE'S BURNING AMP 2018 LINESTAGE, I see some similarity's in UGS and XA252 input stage and the offering in diya store is a balanced version, so you need two PCB's for stereo.
Am I correct ?
Right.. well, I have UGS 4-6 sch, and Wayne's look like a sibling of the PASS UGS6, so could "easily" be modified to SuSy. The main difference between Wayne's and official PASS is same sex JFet (N-chn) and PASS use complimentary. The main difference between UGS5 and UGS6 is that UGS5 uses one degeneration resistor while UGS6 and Wayne is using degeneration for each JFet. But other than this, they are all very similar.
If I redesign Wayne's burning amp line stage into a SuSy and throw in some Schade feedback, I would end up with something unique which started its life in the diya community and would probably be fine...
If I redesign Wayne's burning amp line stage into a SuSy and throw in some Schade feedback, I would end up with something unique which started its life in the diya community and would probably be fine...
well, if you ever start doing it, instead of contemplating, you'll find thing little more complicated
as I personally didn't tried it, I can't tell how SUSY arranged Wayne's LS is going to be stable , regarding output offset ( both differential and absolute)
so, that's first task for you - take one stereo board and make SUSY of it, test stability , offsets and oscillation
as I personally didn't tried it, I can't tell how SUSY arranged Wayne's LS is going to be stable , regarding output offset ( both differential and absolute)
so, that's first task for you - take one stereo board and make SUSY of it, test stability , offsets and oscillation
I happen to have these lying around now, jealous seeing their THF-51S brothers get favored in the Sissy.
Are there any advantages to using a THF-51S vs a 2SK180 & 182ES pairing in the XA252? Or could I use these two up in such a build for the same performance?
ZM has been busy, indeed... Looking forward to seeing these roll out!
Are there any advantages to using a THF-51S vs a 2SK180 & 182ES pairing in the XA252? Or could I use these two up in such a build for the same performance?
ZM has been busy, indeed... Looking forward to seeing these roll out!
value of NFB resistors isn't telling anything?
I did my share of amps with current dominant NFB, also with real current NFB
as always, that is a choice in context
this time, I didn't made that choice, having other aspects as priority and these dictated nature of NFB loop
should we see some result of your tinkering, soon?
I did my share of amps with current dominant NFB, also with real current NFB
as always, that is a choice in context
this time, I didn't made that choice, having other aspects as priority and these dictated nature of NFB loop
should we see some result of your tinkering, soon?