When a pair of speakers are used for mono, it creates the most realistic imaging I've ever heard. The artist just pops into thin air between the speakers--hard to believe that we can't get a good, modern, mono recording.
To create stereo effects takes excellent engineering, which I'm not certain is abundant. Of course, it could be that I'm being lazy--I have to build two amplifiers to have stereo. 😉
who cares for amps
Mighty ZM is exploring these dayz ....... timeless pleasures
look - no left , no right .... just deep down ....... right through the mono
Great!
There is even bettter recording from 1912, half-mono !
Off Topic Mob in action ....... again
AAAaaaiiiiiiiiiiiiiieeeeeeeeeeeeaaaaaaaahhhhhhhh!!!!!!!!!!! 😉
for Buzz & Stajo ....... and Stajo & Buzz
so , I'm dumb
while , few years ago , I was contemplating about these amps I knew that servo is clever thing to have for iteration with CCS loading on top , I didn't realize that for split load choke one doesn't need servo , at least not for having same DC potential on two outputs
(so - it isn't new that I'm dumb , it also isn't new that I know that ..... and what's new is that I realized what's written above
)
reason is so obvious that I don't need to explain it
however - potential mismatch between two output mosfets (Jfets , whatever) can lead to unequal current through two halves ...... and you know that chokes are not humble but humable , when put in that position
in practice , one need to use matched mosfets ( preferably at 2A , where Iq is set ) and any further tweak regarding L-R Iq is easily achieved with small trimpot in source of input Jfet , on more current hungry side
note number 13 - you both know that , irrelevant which part is used here ( IRFP , SJEP , SJDP , cascoded LU - all of them easily adopted with just FB net change ) , max power is in range of , say , 15W/8R
that figure coming from Iq of 2+2A , and load of 8R , which is , in fact , more like 4+4 - at least concerning each half of amp
so , I'm expecting that this thingie is gonna work , maybe without or just little polishing
now , I need to implement some of things simmed here , to Magura's Donuts - to slightly change lower CCS arrangement , just because he was either lazy to implement some NTC correction circ in , or it was absolutely impossible , taking in account that difference in temp between full temp and Dodo of his amps is some 5(five) C
pics are result od LTSpice sim , so usual disclaimer - that's sim ........ and - even more important - sim by Mighty ZM
edit - both pics are for 1W output
so , I'm dumb
while , few years ago , I was contemplating about these amps I knew that servo is clever thing to have for iteration with CCS loading on top , I didn't realize that for split load choke one doesn't need servo , at least not for having same DC potential on two outputs
(so - it isn't new that I'm dumb , it also isn't new that I know that ..... and what's new is that I realized what's written above
)reason is so obvious that I don't need to explain it
however - potential mismatch between two output mosfets (Jfets , whatever) can lead to unequal current through two halves ...... and you know that chokes are not humble but humable , when put in that position
in practice , one need to use matched mosfets ( preferably at 2A , where Iq is set ) and any further tweak regarding L-R Iq is easily achieved with small trimpot in source of input Jfet , on more current hungry side
note number 13 - you both know that , irrelevant which part is used here ( IRFP , SJEP , SJDP , cascoded LU - all of them easily adopted with just FB net change ) , max power is in range of , say , 15W/8R
that figure coming from Iq of 2+2A , and load of 8R , which is , in fact , more like 4+4 - at least concerning each half of amp
so , I'm expecting that this thingie is gonna work , maybe without or just little polishing
now , I need to implement some of things simmed here , to Magura's Donuts - to slightly change lower CCS arrangement , just because he was either lazy to implement some NTC correction circ in , or it was absolutely impossible , taking in account that difference in temp between full temp and Dodo of his amps is some 5(five) C
pics are result od LTSpice sim , so usual disclaimer - that's sim ........ and - even more important - sim by Mighty ZM
edit - both pics are for 1W output
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so , when ready , just say which critters you wanna in
same goes for wakoo Viking
then I'll fire sim again and look at some details
same goes for wakoo Viking
then I'll fire sim again and look at some details
R085 or R065 are most likely candidates. I found out from Mike that R065 is indeed enhancement mode, but with lower Vt than R100 of about .4V.
Question. How do you go about choosing transformer for this amp. I think you suggested 500VA and 110 secondaries. You know me, I dont know squat about chokes and this is first choke loaded amp.
Project down the road, as I am imbedded in another at the moment🙂, but i would like to order toroid now as part of GB.
Question. How do you go about choosing transformer for this amp. I think you suggested 500VA and 110 secondaries. You know me, I dont know squat about chokes and this is first choke loaded amp.
Project down the road, as I am imbedded in another at the moment🙂, but i would like to order toroid now as part of GB.
please - search in Magura's posts what's L of his (air) chokes
then look for biggest toroid you have at home , measure it's primary inductance ( mains disconnected , please ) and you'll know what to expect
I mean 500VA core is minimum , going up can't hurt
I'll make sim with SJEP for which I have models ; later - all you'll need is to fiddle a little with bias pot
CCS mosfet - I recommend IRFP150 - big honker
then look for biggest toroid you have at home , measure it's primary inductance ( mains disconnected , please
) and you'll know what to expectI mean 500VA core is minimum , going up can't hurt
I'll make sim with SJEP for which I have models ; later - all you'll need is to fiddle a little with bias pot
CCS mosfet - I recommend IRFP150 - big honker
Hey Choky,
Sorry for off topic.
Are you still using tube amps? I'm thinking about dipping my toes... got a good thread for me to follow?
Sorry for off topic.
Are you still using tube amps? I'm thinking about dipping my toes... got a good thread for me to follow?
please - search in Magura's posts what's L of his (air) chokes
then look for biggest toroid you have at home , measure it's primary inductance ( mains disconnected , please
I mean 500VA core is minimum , going up can't hurt
I'll make sim with SJEP for which I have models ; later - all you'll need is to fiddle a little with bias pot
CCS mosfet - I recommend IRFP150 - big honker
Whats wrong with testing with connected. BUZZZZZZZ
off topic
yo my woodie man
not really lately , at least not in vivo ; had fingers in making some hybrid ones ( toob susy gain stage by ZM , circlotron out by Juma , previous to that some toob SE shebang gain stage for Ge SE follower (Bata Bane)) , some resurrection of my old WOT preamp ....... ande LTSpicing my UGS called Brynhildr
, which is also hybrid but , luckily , with only toob as active elementhaving too much toobz and parts , few complete monoblocks for restoration , but not enough time ; however - I'm leaving all that for my 70-ies , when I hope will have more time
sweet but fast , for your sweet razor horns - for upper you can choose something based on EL/PL36 in SE triode , for lower maybe the same , only in PP
best to ask residents young ones in toob room - SY and bunch ....... Shoog's balanced thingies are also interesting
Que?
An externally hosted image should be here but it was not working when we last tested it.
you see that I'm connected ....
"Which is the best man to deal with,---he who knows nothing about a subject, and, what is extremely rare, knows that he knows nothing, or he who really knows something about it, but thinks that he knows all?"
--- Thoreau
😀
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