see how is made SE bias on OP chips - same principle , as Pa pointed few times
UGS - I'm really not allowed to say anything about similarity of DIY versions , comparing to origigi PL ......
regarding regs in XS amps, I can't find any hint about in any XS related writing ..... and I didn't ask Pa that ....... so - take my words with grain of salt ;
anyway - Iq is huge in these amps ....... so I really can't believe in existence of any reg
UGS - I'm really not allowed to say anything about similarity of DIY versions , comparing to origigi PL ......
regarding regs in XS amps, I can't find any hint about in any XS related writing ..... and I didn't ask Pa that ....... so - take my words with grain of salt ;
anyway - Iq is huge in these amps ....... so I really can't believe in existence of any reg
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see how is made SE bias on OP chips - same principle , as Pa pointed few times
UGS - I'm really not allowed to say anything about similarity of DIY versions , comparing to origigi PL ......
regarding regs in XS amps, I can't find any hint about in any XS related writing ..... and I didn't ask Pa that ....... so - take my words with grain of salt ;
anyway - Iq is huge in these amps ....... so I really can't believe in existence of any reg
Understandable as far as Pass's production UGSs.
Did NP point out a specific OP amp to look at as a model?
The XSs look like monster and I wonder why then the PSU has big heatsinks....these amps are a masterwork design!!!
....
Did NP point out a specific OP amp to look at as a model?
....!
nope; irrelevant
nope; irrelevant
ahahah...how would that be irrelevant? There are zillions of OPAMPS out there.....
Maybe it would be quicker to open up a X250.5 or a X350.5 and see how it works.
I think I will do that.....too many useless secrets around here in this forums....that are just behind 10 screws...under the hood.... and available to almost anybody....
well , I know how to implement SE bias at OP output and I'm telling you that type of OP is not having anything with that , regarding principle itself.
in short - just put either resistor or CCS , from stage output to neg PSU leg
I'm lazy to look does X*.5 are having Se BIAS , OR IS THAT SOLELY XA*.5 virtue
sorry , caps lock
in short - just put either resistor or CCS , from stage output to neg PSU leg
I'm lazy to look does X*.5 are having Se BIAS , OR IS THAT SOLELY XA*.5 virtue
sorry , caps lock
no don't worry for the caps lock...
Anyway looking at pictures on the net of the X250 and X250.5 looks like they have same number of output devices.
They really look identical, at least from the pictures, for the exception of the UGS which looks like it is using instead of single lower qualuity input devices, uses the SJ108/SK389, which should make up for the sonical difference.
Last I checked my UGS module doesn't even use two devices from the same family...I can't say more as it is a propreitary thing ahahahahaha
Anyway looking at pictures on the net of the X250 and X250.5 looks like they have same number of output devices.
They really look identical, at least from the pictures, for the exception of the UGS which looks like it is using instead of single lower qualuity input devices, uses the SJ108/SK389, which should make up for the sonical difference.
Last I checked my UGS module doesn't even use two devices from the same family...I can't say more as it is a propreitary thing ahahahahaha
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well , I know how to implement SE bias at OP output and I'm telling you that type of OP is not having anything with that , regarding principle itself.
in short - just put either resistor or CCS , from stage output to neg PSU leg
I'm lazy to look does X*.5 are having Se BIAS , OR IS THAT SOLELY XA*.5 virtue
sorry , caps lock
I would think that the SE bias would be solely on the XA which probably has a single end output stahe Aleph's style with the combined front end of the X.5...just my two cents.
Like I said I need to open them up and see how they work
I would think that the SE bias would be solely on the XA which probably has a single end output stahe Aleph's style with the combined front end of the X.5...just my two cents.
Like I said I need to open them up and see how they work
X250 - older generation UGS based FE , follower style OS with mosfet bias gene , 4 mosfets in OS quadrant,no SE bias , 2x38-ish Vdc PSU
XA200.5 - newer UGS based FE , follower style OS with shunt reg bias gene,7 (or 8) mosfets in OS quadrant,SE bias , 2x34-ish Vdc PSU
stefanoo - what I wrote above are facts , not guess
I'm lazy to look does X*.5 are having Se BIAS , OR IS THAT SOLELY XA*.5 virtue
sorry , caps lock
I thought with the statement above you weren't sure.
for the number of MOSFETS I have just checked pictures of the inside on the web, counted the number of output device and concluded they are the same number.
Maybe there are hidden devices don't know, but it's unlikely.
Have you had a chance open both of them?
I don't mean to disregard your fact by any mean and I appreciated your effort in answering my questions
in short - just put either resistor or CCS , from stage output to neg PSU leg
sorry , caps lock
Thanks, This was a rather short but clear explanation.
.......
for the number of MOSFETS I have just checked pictures of the inside on the web, counted the number of output device and concluded they are the same number.
........
few different revisions of output stage , at least to my knowledge
later iterations are having more outputs
just count them in XA30.5 ..........
oh maybe there was a misunderstanding.
I thought you meant that the X250 and X250.5 have different number of mosfets.
Maybe you are referring to the XA200.5 I am not sure
I am alsmost tempted to buy another X250 and use both for parts to re-do board and build two monoblocks which double Idle Current and different front end and single ended output bias.
I think it could be a nice experiment
I thought you meant that the X250 and X250.5 have different number of mosfets.
Maybe you are referring to the XA200.5 I am not sure
I am alsmost tempted to buy another X250 and use both for parts to re-do board and build two monoblocks which double Idle Current and different front end and single ended output bias.
I think it could be a nice experiment
I will check pictures on the web and compared them to my unit, but again, it looks like they have same number of output devices, why don't you check for yourself?
Not trying to question your facts, just showing you some pics and wonderring whay is that.
yeah I 100% agree with you.
I am not going to do it now as I am working on something else and don't have much time.
I am just collecting some ideas and thoughts and I will engage on this once I have worked the circuit out in my mind, simulated it and got 100% confidence with it as I do with anything else I build for myself and for others
I will need pleanty of Liras ahahah in my case Dollars, true; however if you think things right, you will see you won't need as much money as building everything from scratch.
Just think how much it would cost you or me to buy a custom Plitron Transformer (selected for noise), 2 sets of 12 matched output devices, a wonderful finished chassis all the filter caps and why not rectifying diodes and last but not least important heatsinks for your output devices that are not only going to do their job but also going to match your enclousure and extremely nice looking as well.
I mean this much more than what you could pay for a X250.
Regarding speakers, I don't only need power but quality also....and you can go if you want to find me a better pair of speakers than my B&W800Signature and I will gladly take them (obviously without spending more than that).
BTW you forgot that along with good speakers you need to have a good preamplifier and good source and good cable gears before even thinking of improving or having a higher power Power AMP.
I haven't mentioned that but I got everything and that is why I think it would be nice to perhaps trying to build something myself with the basic idea above and then later on get a serious gear such as X600.5 or XA200.5 granted that they could possibily be better than what I am eventually going to make
Not trying to question your facts, just showing you some pics and wonderring whay is that.
yeah I 100% agree with you.
I am not going to do it now as I am working on something else and don't have much time.
I am just collecting some ideas and thoughts and I will engage on this once I have worked the circuit out in my mind, simulated it and got 100% confidence with it as I do with anything else I build for myself and for others
I will need pleanty of Liras ahahah in my case Dollars, true; however if you think things right, you will see you won't need as much money as building everything from scratch.
Just think how much it would cost you or me to buy a custom Plitron Transformer (selected for noise), 2 sets of 12 matched output devices, a wonderful finished chassis all the filter caps and why not rectifying diodes and last but not least important heatsinks for your output devices that are not only going to do their job but also going to match your enclousure and extremely nice looking as well.
I mean this much more than what you could pay for a X250.
Regarding speakers, I don't only need power but quality also....and you can go if you want to find me a better pair of speakers than my B&W800Signature and I will gladly take them (obviously without spending more than that).
BTW you forgot that along with good speakers you need to have a good preamplifier and good source and good cable gears before even thinking of improving or having a higher power Power AMP.
I haven't mentioned that but I got everything and that is why I think it would be nice to perhaps trying to build something myself with the basic idea above and then later on get a serious gear such as X600.5 or XA200.5 granted that they could possibily be better than what I am eventually going to make
no dispute at all .....
except fact that we are having diametrically different taste for spks , so - in case of you - any recommendation from me is nonsense
anyway look at this , X250 :
X250.5 (which I didn't commented ) : (attached)
XA200.5 :
conclusion - none combination of these (X250 , X250,5 and XA200.5) is having same number of outputs ........ and , just to repeat , none of them is having any resemblance of Aleph OS
disclaimer - my (secret spy) little bird at PL is sometimes tricky , maybe because I'm asking silly things all the time
except fact that we are having diametrically different taste for spks , so - in case of you - any recommendation from me is nonsense
anyway look at this , X250 :
X250.5 (which I didn't commented ) : (attached)
XA200.5 :
conclusion - none combination of these (X250 , X250,5 and XA200.5) is having same number of outputs ........ and , just to repeat , none of them is having any resemblance of Aleph OS
disclaimer - my (secret spy) little bird at PL is sometimes tricky , maybe because I'm asking silly things all the time
Attachments
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Different taste of speakers....
Interesting!
Keep only in mind that the most prestigious studio recordings have these speakers for their high quality mixing.
Casuality? Commercial reasons? I don't think so.
The 800Signature and the lateat 800 Diamond are simply the most neutral and transparent speaker you can buy that can actually be employed to create the original master recording that you will go listen through your system and probably alter and colour with other type of speakers
Now I am not saying the 800 are perfect and that there are not other good speakers out there, just that they are among the very best!!!
If you have another pair of 20-25K speaker then we can discuss about personal taste, otherwise it would be like comparing apple with oranges only because they both have round shapes.
Said that, to complete your thoughts on the X250, your picture referes to the first prodcution.
On mine, the latest one, I don't have TO3.
Mine looks EXACTLY like the last picture you posted which is the X250.5
I will attach some pic tonight if you want me to, that will help clear out this little debate
Interesting!
Keep only in mind that the most prestigious studio recordings have these speakers for their high quality mixing.
Casuality? Commercial reasons? I don't think so.
The 800Signature and the lateat 800 Diamond are simply the most neutral and transparent speaker you can buy that can actually be employed to create the original master recording that you will go listen through your system and probably alter and colour with other type of speakers
Now I am not saying the 800 are perfect and that there are not other good speakers out there, just that they are among the very best!!!
If you have another pair of 20-25K speaker then we can discuss about personal taste, otherwise it would be like comparing apple with oranges only because they both have round shapes.
Said that, to complete your thoughts on the X250, your picture referes to the first prodcution.
On mine, the latest one, I don't have TO3.
Mine looks EXACTLY like the last picture you posted which is the X250.5
I will attach some pic tonight if you want me to, that will help clear out this little debate
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previous post (to quoted one) was maybe little confusing; anyway - look at my last post - one picThis is a cool picture BTW
amps are - from left to right - X250 , X250.5 , XA200.5
regarding your and mine spks - there is no use in trying persuading ZM in liking modern speakers ....... I'm completely on romantic side of speakers
I'm pullin' your leg , and really not saying that your speakers aren't great ( even if I really don't care for them ) , so - it's completely irrelevant what's my reference .
so - you're having transitional model , between X250 and X250.5
probably even Pa can't remember all variations during all these years .
what's important - you're having great amp , it doesn't matter which generation it is ......
you are not alone though!
I know many other people who don't like modern speakers and they have their good reasons that I might not have fully grasped yet.
I don't know, all I know is that I have a X250 and it looks exactly like the 250.5, but I am sure like you said there are significant variations and you really helped me pointing out good points regarding output bias, thanks for that!
I will attach some pics tonight just for your fun
I know many other people who don't like modern speakers and they have their good reasons that I might not have fully grasped yet.
I don't know, all I know is that I have a X250 and it looks exactly like the 250.5, but I am sure like you said there are significant variations and you really helped me pointing out good points regarding output bias, thanks for that!
I will attach some pics tonight just for your fun
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