Meanwhile the M2 pcbs rest patiently while I suppress the urgeto hear them by dissassembling my lovely F6.
Go for it. I turned my F6 into Aleph J, no looking back. Both Aleph J and M2 more enjoyable than F6 in my opinion.
Russellc
it really depends of combination with speakers and , highly subjective and unique judging equipment
so , M2 is no better than F6
even if it's The Best of all sane FW amps
so , M2 is no better than F6
even if it's The Best of all sane FW amps
Even if the M2 shows it self to be superior on my horns the F6 will live and might be tweaked for additional W later. It is wonderful on my renovated Carlsson OA-51LE2 in the high WAF system (old picture), where Im currently using hypex ncore nc400 monoblocks.
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M2 Complete
Finished the M2 build with Toshiba 1530/201s on Sunday and it performs as promised and suggested by a number of you. I listened to it briefly (visitors) through the OB Lowthers only and was surprised with the slam and drive and tempo. I thought I was playing the tunes bit faster than usual. Soundstage very different. Monday I replaced the F6 with the M2 to handle the low end for OB and Aleph J on high. Stunning. Exciting. No time to burn it in. Females voices van Otter, Alison Kraus, Kozena richer and more lovely than I ever heard. And close to the kind of sound you hear from the very best gear (expensive) at the audio shows. Thanks everyone. This hobby is ridiculously rewarding.
Finished the M2 build with Toshiba 1530/201s on Sunday and it performs as promised and suggested by a number of you. I listened to it briefly (visitors) through the OB Lowthers only and was surprised with the slam and drive and tempo. I thought I was playing the tunes bit faster than usual. Soundstage very different. Monday I replaced the F6 with the M2 to handle the low end for OB and Aleph J on high. Stunning. Exciting. No time to burn it in. Females voices van Otter, Alison Kraus, Kozena richer and more lovely than I ever heard. And close to the kind of sound you hear from the very best gear (expensive) at the audio shows. Thanks everyone. This hobby is ridiculously rewarding.
A few days ago I hooked up the M2 in my TV setup and it has improved meanwhile a lot. Back in the main listening setup I cannot say that there is any lack in details and low frequency edge. Quite contrary it happened to me that I skipped songs back because I heard very low frequency sounds never recognized before and had to find out if it was sound from outside or from the recording.
Dont know if the improvement is caused by burn-in or my internal adjustment.
When I mounted the shields on the edcors I have touched accidentally with a magnetic screwdriver the transformers few times. Perhaps the edcors needed to demagnetize over time.
The M2 is a keeper which I really enjoy. Will build a second one using the M2X boards and I am interested how the mountain view input boards will sound.
Haven't heard with the Tosh's. I'm using IRF IRFP140 and Harris IRFP9140 to very satisfying results.
Maybe someday we could compare, neighbor.
Dear all,
Please some help…
I have a strange (at least for me) problem with my mono’s…..
Everything is ok….all measurements are perfect….DC out 2-3 mV….Voltage across source resistor 0.63V on both channel’s and stable…power supply steady at 2x22.5V and sound is terrific, slightly better than my favorite, till now, Aleph J.
The problem is that, BOTH CHANNELS, at the first 15 seconds are dead quite than they are starting to hum. Noise is like when there is ground loop and can be heard from cca 15cm from the speakers. Ground is connected at this way. One lead is via 10ohm thermistor to chassis ground, the rest goes – one to amplifier board and second to speaker binding post (from power supply). I’ve tried with removing interconnects, shorted input…still the same….
I suspect that transformer witch feed DC speaker protection is close to Edcor though is approx 20cm away. Case is 300mm high and 400mm depth.
I don’t think that there is cold joint…
If you have any suggestion please let me know….
Thank You at advance,
Toni
Please some help…
I have a strange (at least for me) problem with my mono’s…..
Everything is ok….all measurements are perfect….DC out 2-3 mV….Voltage across source resistor 0.63V on both channel’s and stable…power supply steady at 2x22.5V and sound is terrific, slightly better than my favorite, till now, Aleph J.
The problem is that, BOTH CHANNELS, at the first 15 seconds are dead quite than they are starting to hum. Noise is like when there is ground loop and can be heard from cca 15cm from the speakers. Ground is connected at this way. One lead is via 10ohm thermistor to chassis ground, the rest goes – one to amplifier board and second to speaker binding post (from power supply). I’ve tried with removing interconnects, shorted input…still the same….
I suspect that transformer witch feed DC speaker protection is close to Edcor though is approx 20cm away. Case is 300mm high and 400mm depth.
I don’t think that there is cold joint…
If you have any suggestion please let me know….
Thank You at advance,
Toni
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Doesn't it take 15-25 seconds for the bias current to ramp up? So maybe the hum is 'permanent' but only audible when the amp warmed up a little? (At my tests music started after about the same 15-25 seconds).
I can't see anything wrong
anyway , if amp is in steady state behaving as intended , just increase RC constant in speaker protection/delay circuit , so jump across humming interval
anyway , if amp is in steady state behaving as intended , just increase RC constant in speaker protection/delay circuit , so jump across humming interval
Instead of taking your speaker ground from the power supply board try taking it from the amplifier board (the out g ) point.
Following Attila I and Russell measurements
I had a heat issue with Q1 on the right channel (resolved) so I thought it was time to measure the voltages at A: B: C: and offset for that channel.
A: 84mV, B: -52mV, C: 13mV, DC offset: 52mV. Following an earlier suggestion of ZM, I paralleled R4 with a 10R+10R resistor and then measured 3mV at C. All jets are BL and the 2sj74 on the Right Channel was recycled from an old F5 build.
Measurements now:
LEFT...........RIGHT
A: 64mV.......76mV
B: -70mV......-45mV
C: -2mV........ 3mV
R13: .580,,,,,,.573
R14: .582,,,,,,.572
DC Off: 0........0
So, my question, is the wide difference btw Right channel A and B measurements an issue? And is the -2mV measurement on Left's C: an issue?
Thanks for the help.
I had a heat issue with Q1 on the right channel (resolved) so I thought it was time to measure the voltages at A: B: C: and offset for that channel.
A: 84mV, B: -52mV, C: 13mV, DC offset: 52mV. Following an earlier suggestion of ZM, I paralleled R4 with a 10R+10R resistor and then measured 3mV at C. All jets are BL and the 2sj74 on the Right Channel was recycled from an old F5 build.
Measurements now:
LEFT...........RIGHT
A: 64mV.......76mV
B: -70mV......-45mV
C: -2mV........ 3mV
R13: .580,,,,,,.573
R14: .582,,,,,,.572
DC Off: 0........0
So, my question, is the wide difference btw Right channel A and B measurements an issue? And is the -2mV measurement on Left's C: an issue?
Thanks for the help.
sorry , can you point us to where reference (schmtc) for A, B , C points is ?
now going to lawn move ..... 'll be back in month or so
now going to lawn move ..... 'll be back in month or so