NOOOO! Don't do that! Well, I've never heard an M2, but my J2 was the most magical amp I'd ever heard.
Until my SIT2 came along. 😀 I just can't bear the thought of cannibalizing a J2.
First of all, I run all my class A amps with low capacitance followed by the PowerReg so not that much of added cost.
Second, and I don't want this to sound as sacrilege, one may try to improve those amps...
I added a differential amplifier to my single ended Tokin SK180 amp and it significantly improved.
Now I am ready to cascode that common-source amp, since my recent experience cascodying the ZCA (Zero component amp from Mark Houston; 2SK1058) with BJT, showed also improvement in all departments.
The J2 is also a candidate to cascodying both sections and even the CCS, but It may be more tricky... 🙁
Third, having lots of amp almost forces you to consider active multi-amplification. Though class A multi-amp would be to much heat probably...
Sorry to be so mono-thematic. 😀
Cheers,
M.
eh but the PSU i want to build will have adjustable voltage from 18V to 60V 😀 Or maybe i'll need to split in two ranges (18-30 and 36-60 or something like that)
L'amp variations I have made are my favorite as well. I still use AJ and digital amps due to practical reasons, power and heat.
Thanks for your support 🙂
previously when i build my amplifier, i never thought about my speaker load. now with my fullrange OB, no need for any xo, or difficult load on subwoofer which has it's own class d + dsp.
early 2017 when i completed my amplifiers but still used 3way floorstand and alpair10p, i still had a dream to build Aleph2 monoblock. it seems cool for that huge heatsink, just scale up my L'amp diy case.
everything changed when I used high sensitivity 8" fullrange in mid 2017, no need for massive power anymore.
the good thing is that i had build separate power supply box with neutrik powercon, it is very easy to swap between J2 and M2.
I also had a plan to build F2 with to-3 irfp, it will be cool 🙂 or F2J with my spare R100 from J2 ccs, or the new introduced MoFo, these still can use same FW psu.
but maybe it's my time to hibernate (yes not stop) building class a amplifier. my stupid behaviour not to listen to music before, only to find my build work or not, now my earn & brain just realised that there is alooot of differences when i listen to music when my gear up vs 1hour warm up. big and huge differences.
as you can see, my amplifiers already occupied my diy rack, i have to build another small rack for non-amplifier.
with 3x5m living room, not many space available. on the right side of the picture, i have 5x6m backyard which i'm going to build as livingroom expansion, hence all audio gear can move there plus maybe proper room treatment.
previously when i build my amplifier, i never thought about my speaker load. now with my fullrange OB, no need for any xo, or difficult load on subwoofer which has it's own class d + dsp.
early 2017 when i completed my amplifiers but still used 3way floorstand and alpair10p, i still had a dream to build Aleph2 monoblock. it seems cool for that huge heatsink, just scale up my L'amp diy case.
everything changed when I used high sensitivity 8" fullrange in mid 2017, no need for massive power anymore.
the good thing is that i had build separate power supply box with neutrik powercon, it is very easy to swap between J2 and M2.
I also had a plan to build F2 with to-3 irfp, it will be cool 🙂 or F2J with my spare R100 from J2 ccs, or the new introduced MoFo, these still can use same FW psu.
but maybe it's my time to hibernate (yes not stop) building class a amplifier. my stupid behaviour not to listen to music before, only to find my build work or not, now my earn & brain just realised that there is alooot of differences when i listen to music when my gear up vs 1hour warm up. big and huge differences.
as you can see, my amplifiers already occupied my diy rack, i have to build another small rack for non-amplifier.
with 3x5m living room, not many space available. on the right side of the picture, i have 5x6m backyard which i'm going to build as livingroom expansion, hence all audio gear can move there plus maybe proper room treatment.
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zenlite
Hello,
I would like to mount a zen-lite amp with 2x 300w / 130v per channel, with THF51S transistor, do I have to change the original schematic?
thank you for the tips before starting ...
cordially
Hello,
I would like to mount a zen-lite amp with 2x 300w / 130v per channel, with THF51S transistor, do I have to change the original schematic?
thank you for the tips before starting ...
cordially
i just read again Papa article for current source amplifier, is SIT L'amp a kind of CSA? when I compare to F2 schematic, it looks similar topology
to Vallo85
There is little information on the THF51S, but it has been suggested that the 2SK180 is a similar widget and would be a good starting point approximation.
There is information on the 2sk180 on various threads by Michael Rothacher and also on his website blog.audiomaker.tech and youtube videos
Look also at L'amp threads and sony Vfet amplifier part 2 (around post 3370)
There is little information on the THF51S, but it has been suggested that the 2SK180 is a similar widget and would be a good starting point approximation.
There is information on the 2sk180 on various threads by Michael Rothacher and also on his website blog.audiomaker.tech and youtube videos
Look also at L'amp threads and sony Vfet amplifier part 2 (around post 3370)
Heya - could anyone tell me what the package name for the 2sk182 is? Or more to the point, where do I get an insulator for these parts? Thanks in advance!
TO-3
I bought mine from Mouser. Digikey probably stocks it too. What I bought was "Keystone Electronics Part No. 4725", TO-3 Insulator Mounting Kit.
I bought mine from Mouser. Digikey probably stocks it too. What I bought was "Keystone Electronics Part No. 4725", TO-3 Insulator Mounting Kit.
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Ummm, perhaps I got some details wrong there? The 2sk182 is the next size/package up from TO-3.
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Google Image Result for http://img01.taobaocdn.com/bao/uploaded/i1/T124egXb0xXXXDQTI._083542.jpg_310x310.jpg
Dear all,
L' Amp style amps, while being wonderful, may be seen (at least I see) as starting points in the learning experience and I cannot avoid wondering about many experiments to be done, like CCS, cascoded CCS, cascoded VFET, which are some of the steps to add to my already modded amp.
I have been using my Tokin amp with a differential amplifier for the input and it really improved a lot.
As some may know, I am experimenting with Peufeu's recommendations for diminishing (putative) thermal memory distortion effects, like the cascoded-CFP input pair. Well, yesterday I replaced the input pair differential with a "cascoded-compound CFP" pair of units, using Toshiba's SK170 as both, the cascodying element and as the "driver" of the CFP pair and a BC560 PNP as the "emitter follower" of the pair, with a 1K resistance on its emitter. I confess I studied some academic articles about this compound Szicklai but they were too much for me, so I took the plunge as the good Lord seemed to advice me...and it worked! 😀
First listening tests are very encouraging. 😎
I attach picture of the cascode-compound CFP units and a diagram of the target amp...
I hope you like it.
M.
L' Amp style amps, while being wonderful, may be seen (at least I see) as starting points in the learning experience and I cannot avoid wondering about many experiments to be done, like CCS, cascoded CCS, cascoded VFET, which are some of the steps to add to my already modded amp.
I have been using my Tokin amp with a differential amplifier for the input and it really improved a lot.
As some may know, I am experimenting with Peufeu's recommendations for diminishing (putative) thermal memory distortion effects, like the cascoded-CFP input pair. Well, yesterday I replaced the input pair differential with a "cascoded-compound CFP" pair of units, using Toshiba's SK170 as both, the cascodying element and as the "driver" of the CFP pair and a BC560 PNP as the "emitter follower" of the pair, with a 1K resistance on its emitter. I confess I studied some academic articles about this compound Szicklai but they were too much for me, so I took the plunge as the good Lord seemed to advice me...and it worked! 😀
First listening tests are very encouraging. 😎
I attach picture of the cascode-compound CFP units and a diagram of the target amp...
I hope you like it.
M.
Attachments
Good work!
If you put a 2 stage constant current source where R5-R7 are, the performance will be even better. That will probably also allow you to get rid of the balancing pot (which degrades the differential effect) as well.
If you put a 2 stage constant current source where R5-R7 are, the performance will be even better. That will probably also allow you to get rid of the balancing pot (which degrades the differential effect) as well.
Thanks!
The amp is sounding glorious. It does not collapse with complex music. Lots of microdetail and great textures and timbral accuracy.
The resistor tail was chosen by the designer for better sonics.
If I were to remove it, I would experiment with cascoded CCS. Is that what you refer to with "2 stage"?
The balancing pot equilibrates the currents. I don't understand what you meant... 😕
This cascoded-CFP mod is a great discovery. I am modifying all my circuits with them.
Next is the output of my SuperDAC and an amp with a capital letter and and number by name 😀
Cheers,
M.