| YES 10 pieces is cheaper than 8 may opt for digikey 1189-3914-ND 27K 35V Mfr Rubycon on BOM Thanks |
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I was just doing a listening comparison between Aleph Jzm and F5m.
Both are wonderful sounding amps. The F5m sings and sparkles in the highs and has great authority with bass. However, when I put it up against the Aleph Jzm, the latter stands out with is extremely powerful bass authority and silky smooth mids. If you made me vote, the Aleph Jzm is just one level above the F5m overall. I can't tell you why in detail, but it just is a step above on securing the seat of authority over the F5m. Two great amps!!!! So much fun to be able to compare the two back to back on the same system.
What a wonderful gift to be able to compare the two amps. You can't go wrong with either option.
Both are wonderful sounding amps. The F5m sings and sparkles in the highs and has great authority with bass. However, when I put it up against the Aleph Jzm, the latter stands out with is extremely powerful bass authority and silky smooth mids. If you made me vote, the Aleph Jzm is just one level above the F5m overall. I can't tell you why in detail, but it just is a step above on securing the seat of authority over the F5m. Two great amps!!!! So much fun to be able to compare the two back to back on the same system.
What a wonderful gift to be able to compare the two amps. You can't go wrong with either option.
The Aleph I have (original) is indeed colored in sound, my original F5 not so much, very accurate.
My preference is for the aleph J. Colored, but beautifully so!
Russellc
My preference is for the aleph J. Colored, but beautifully so!
Russellc
I have not gotten the notice yet. When it shows up it will probably spur me into action. Been doing family gatherings and yard work lately....
Dbt test complete. No smoke! 24v +\- on both sides. Time to take a break, then start connecting first side of amp.After some sparks for going to fast, everything turned out fine. Unplugged DBT, straight to wall. No smoke. Again 24v +\-.
Wait till caps are not charged to connect first side!
My parts are still in the sack. Board is still unpopulated. Once it gets here will be another story, but have to get XA 252 channel fixed first.
First amp board passed dbt test, and plugged directly to wall. Now wait till caps discharge for second side.
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Indeed it sings! No issues here. Now to let it play and tweak bias and dc offset!
What is the recommended thermic resistance of a heatsink in W/celsius for the fet pair? Minimum/recommended
Hi here...
Back in 2016 I made the link (Alephj mini custom).
I'm considering making an upgraded one, with lower rails as in my old thread. My plan is to make two dual mono ones using the balanced input with fully balanced source preamp / dac etc...
I was wondering if anyone had calculated for lower rails for approx. 100W dissipation instead of the ~200W for the "big" Aj@Zm one here.
And oh another thing? Is there any particular reason why the ouput now consist of one IRFP150 instead of the original two IRFP240's.
Jesper.
Back in 2016 I made the link (Alephj mini custom).
I'm considering making an upgraded one, with lower rails as in my old thread. My plan is to make two dual mono ones using the balanced input with fully balanced source preamp / dac etc...
I was wondering if anyone had calculated for lower rails for approx. 100W dissipation instead of the ~200W for the "big" Aj@Zm one here.
And oh another thing? Is there any particular reason why the ouput now consist of one IRFP150 instead of the original two IRFP240's.
Jesper.
Calculating is easy... but I don't know how it will perform. You almost certainly will have higher distortion if you lower bias current. Will it matter to you... only you know. ZM may have tried it lower than I did.
You could also lower the rails... I think I've seen 20V ... and maybe as low as 18V
ZM would have better guidance re: any major potential issues with lower rails and how low you could safely go.
No matching required. Makes it easier for (newer) builders (and those that supply the kits).
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I wouldn't go bellow 15Vdc rails, reason being interelectrode capacitances of mosfets more wakoo with lower rails voltages
you can't be so precise about exact voltage (18Vdc is already bad enough) but man must draw a line in sand somewhere
few resistor changes to optimize for 15V rails and lower Iq, but no biggie
IRFP150 is practically 2pcs of IRFP240 in one case
you can't be so precise about exact voltage (18Vdc is already bad enough) but man must draw a line in sand somewhere
few resistor changes to optimize for 15V rails and lower Iq, but no biggie
IRFP150 is practically 2pcs of IRFP240 in one case
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Thanks both...
I will make the rails around +/- 19.5 as this is what I use for the Alephj Mimi.
I'm going to measure the distortion on this one old Mimi also (I think bias is 1.2) Donno why I never did that 😳
Anyway I suppose I need to stick with IRFP240 now that I don't need so many watts, or should I try the IRFP150 (will study the datasheets).
Any opinion on this?
Jesper.
I will make the rails around +/- 19.5 as this is what I use for the Alephj Mimi.
I'm going to measure the distortion on this one old Mimi also (I think bias is 1.2) Donno why I never did that 😳
Anyway I suppose I need to stick with IRFP240 now that I don't need so many watts, or should I try the IRFP150 (will study the datasheets).
Any opinion on this?
Jesper.