Pics of my utilitarian 😀 F5 V2 monoblocks. Biased @ 320mV with ~8mV offset. Haven't had the chance to play with P3
Boards from indian group buy DIY: Pass F5 turbo v2 initiated - Page 18
Mosfet (perfectly matched) & diodes from Buzz
300VA, 8x15K caps per channel. Heatsinks are 500mm long with 125 mm width (not optimum config, but was cheap and handles the heat very well)
F5 vanilla didnt work for me, Aleph J set the bar pretty high, F5T V2 sailed over the bar (by a few centimeters 🙂).
Boards from indian group buy DIY: Pass F5 turbo v2 initiated - Page 18
Mosfet (perfectly matched) & diodes from Buzz
300VA, 8x15K caps per channel. Heatsinks are 500mm long with 125 mm width (not optimum config, but was cheap and handles the heat very well)
F5 vanilla didnt work for me, Aleph J set the bar pretty high, F5T V2 sailed over the bar (by a few centimeters 🙂).
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Good to know. After my KSA50 clone which is almost finished now I am tackling an Aleph J, and then F5TV2. I was thinking of doing the F5TV3, but realistically it will not fit in my budget at the moment. Maybe later. The F5TV3 requires a mean PSU and heatsinks which will costs a lot of money, unless you do heat tunnels with fans like a Krell KSA100.
Nice work. An aleph J with ultiple outputs would pull it back in a little. That extra grunt is one of the big differences. Just more at ease in its presentation.
Oh yes an AJX is exactly what is on my mind 🙂.I have the boards, most parts, understanding (hopefully) of what needs to be done for a 40 Watt AJX.
Oh yes. The AJX will definitely pull it back in. When its done, youll have comparable power and you will then be hearing topology difference.
don't forget that grunt depends of current capability
each half of X is seeing half of load
go figure what that means for number of outputs , at least by my twisted logic
if J is having 2 pairs in output , I would go with 8 pairs for XJ
there is no much brain in using different logic from Pa's , when going bigger
( do not ask how I came to that conclusion
)
each half of X is seeing half of load
go figure what that means for number of outputs , at least by my twisted logic
if J is having 2 pairs in output , I would go with 8 pairs for XJ
there is no much brain in using different logic from Pa's , when going bigger
( do not ask how I came to that conclusion
)
Yup. gonna need more current. about 2.5A per channels for 50W. But you can drop the rails, correct, as voltage sums across the load. Bridged gives you double power into double the load, if you got the current. Wonder of AJX maintains classic Aleph signatture or does X, X it out
Option 1--8 irfp240 mosfets each being fed 1 A supplied by 16V rails
Option 2 -- 4 irfp150 mosfets each being fed 2 A supplied by 16V rails (ZM just squashed this 🙂)
I'll try both.
The funniest part is that i'm currently ravaging the AJ, one channel with 1 pair (1A each @ 24V), the other channel 2 pairs (1A each @ 24V), i hear no difference, guess my 8 ohm spk's are real 7~8 ohm (not current hungry) (or) my headphones have shorted 🙂 🙂
Lets just stay on F5T 🙂 🙂
Option 2 -- 4 irfp150 mosfets each being fed 2 A supplied by 16V rails (ZM just squashed this 🙂)
I'll try both.
The funniest part is that i'm currently ravaging the AJ, one channel with 1 pair (1A each @ 24V), the other channel 2 pairs (1A each @ 24V), i hear no difference, guess my 8 ohm spk's are real 7~8 ohm (not current hungry) (or) my headphones have shorted 🙂 🙂
Lets just stay on F5T 🙂 🙂
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I would add another 300va transformer to maximize your output stage and for best sonics , a single 300va is way too small ..
Here is retry of distortion measurement of my F5T. Slightly adjusted for higher 2k to 3k. THis gave the widest and best overall soundstage.
Buzz,
maybe a stupid question, but is the blue line 2nd order distortion? is there no 3rd order distortion at all? Or am I reading the graph completely wrong?
THe blue line is the soundcard in loop back. Red is the amp. Look at the bottom of the graph for the frequency for the distortion. It was tested at 1k, so you see a spike there. Then 2k and 3k, falling in pretty good relation. Have a tiny bit of 5k, which i dont like, but unsure of how to get rid of it.
The peak at 2KHz is below -90 dB and the signal at 3KHz is below -100 db (there is a trace at 4Khz but it is below -120db). This is pretty good.
Regards,
I fired up my F5T V2 this afternoon and one channel was adjustable as req'd but the other one would'nt go above .32V before the trimmer started clicking.I know I need to increase the value of R5/6 but wondered is there a resistor value to use and is it worth changing them on both boards?
Ignore this I found the answer in #971.Thanks Audiosan
Ignore this I found the answer in #971.Thanks Audiosan
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