Slagelformers and the M2
Hi,
I use Dave's autoformers in a passive pre with a factory built M2 and it's a lovely sound. Almost like tubes without the trouble. Not SET sound...more like PP transformer coupled 6550s in a very high quality amp. I use low efficiency speakers too.
It's likely that the difference between the autoformer and the Aikido with the M2 that you are experiencing is related to gain. I think it takes 3V to drive the stock M2 to full output. If your sources are lower or much lower in output, than the Aikido is going to give a greater sense of "drive" to the sound.
Kindest regards,
Chris
Hi,
I use Dave's autoformers in a passive pre with a factory built M2 and it's a lovely sound. Almost like tubes without the trouble. Not SET sound...more like PP transformer coupled 6550s in a very high quality amp. I use low efficiency speakers too.
It's likely that the difference between the autoformer and the Aikido with the M2 that you are experiencing is related to gain. I think it takes 3V to drive the stock M2 to full output. If your sources are lower or much lower in output, than the Aikido is going to give a greater sense of "drive" to the sound.
Kindest regards,
Chris
I have a set of SE 300b monoblocks, and two sets of PP ( pentode) valve monoblocks ( one set pentode coupled and the other partially triode coupled ) to compare. I just thought the M2 was faar too laid back/slow. Started to think my double mono supply was too slow (4x47000uf per side) might be better to decouple with some smaller caps? Or maybe its me, ie that I need to get to terms with the soft and relaxed way the M2 conwey music. The M2s are free of any hum or noise, so much so that I think I need to rewisit the wiring in my F6. My Altec A5, speakers are very effective, but even with highly transparent simple xowers with autoformer level adjustment, quite picky and need more effect than one would expect from such effective speakers.
And Im not saying the M2s are bad in any way, Its a great amp, but for me and my current system I suspect the F6s are the better amps/ FW flavour
.
And Im not saying the M2s are bad in any way, Its a great amp, but for me and my current system I suspect the F6s are the better amps/ FW flavour
.
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@ Kbergsson
You can agree with me now M2 are very quiet like all Mr Pass amplifiers as well
if correct configuration with the others audio chain elements.
Choice of specific audio source for maximal enjoyment from the amplifiers is frequently neglected.
Class A amplifier, but not pure class A, no feedback stages I/V inside of the DAC.
My triode single-ended CD player are happy companion to autoformer volume control, M2 and 12" alnico wide ranges.
I can share with Chris the same point of vue
Kindest regardsAttachments
CD player are DIY modify by me ( much better capacitors and resistors , other triode's and psu filtering )
and this autoformers are not new commercial products, is home & hand made and old.
Ask Zen Mod he knows how to do it some "Turtle" balanced or single version of autoformers and more.... Greetings
and this autoformers are not new commercial products, is home & hand made and old.
Ask Zen Mod he knows how to do it some "Turtle" balanced or single version of autoformers and more....
GreetingsCommercial First Watt M2 is one of the most morphing amps with break in I have heard.
Started out wonky and wobbly (cured by leaving on for a week) to become wholistic and organic. Now, after a several hundreds of hours, much more refined and seemingly just getting better. So, I guess it is not an instant gratification amp. It still has the wholism and PRAT.
At this stage, I would rather poorly describe it as having the crunchiness of a nice el 84 amp with the spaciousness of a 300b, although it probably isn't entirely fair to compare it to tubes. Crackling voices on microphones really crackle, saxaphone blats really blat.
A bit more splashiness in the highs might be nice, although upper midrange sheen is very nice, but who knows, maybe after more use.
Since most amps seem to be judged and described in their first 50 to 100 hours or so, I would probably leave it plugged in and on for the first month or two of use to move it along.
I have used it with both solid state and tube preamp stages, both work very well with it, though I prefer the tube.
Started out wonky and wobbly (cured by leaving on for a week) to become wholistic and organic. Now, after a several hundreds of hours, much more refined and seemingly just getting better. So, I guess it is not an instant gratification amp. It still has the wholism and PRAT.
At this stage, I would rather poorly describe it as having the crunchiness of a nice el 84 amp with the spaciousness of a 300b, although it probably isn't entirely fair to compare it to tubes. Crackling voices on microphones really crackle, saxaphone blats really blat.
A bit more splashiness in the highs might be nice, although upper midrange sheen is very nice, but who knows, maybe after more use.
Since most amps seem to be judged and described in their first 50 to 100 hours or so, I would probably leave it plugged in and on for the first month or two of use to move it along.
I have used it with both solid state and tube preamp stages, both work very well with it, though I prefer the tube.
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to invoke all of what M2 is capable, one must have source side completely solved
that includes preamp stage too .....
M2 is not slow , neither too fast ...... just right
add to that too slow preamp , there is a problem - slow sounding system
you can sometimes use slow preamp with tube output, paying lesser price/damage .... tube outputs are always sort of twichie , eager to run , so compensating deficiency upstream
not saying that's bad thing , just needing to count in bigger picture
that includes preamp stage too .....
M2 is not slow , neither too fast ...... just right
add to that too slow preamp , there is a problem - slow sounding system
you can sometimes use slow preamp with tube output, paying lesser price/damage .... tube outputs are always sort of twichie , eager to run , so compensating deficiency upstream
not saying that's bad thing , just needing to count in bigger picture
Thanks for comments and suggestions. There is no doupt that I can do better with regard to my sources. I wont write off the M2 yet
@Soundhappy, I agree the M2 is currently more quiet than my F6.
@ZM slowness is without tube pre, only autoformer.
I had a good ( Unneccesary much gain) Leben pre&phono a couple of years ago but I exchanged the Leben for my current Altec A5/1505b horn setup. I got a pearl2 pcb but I might also built a tube phono stage. I will start by buffering the output from my boozehound phono ( pacific phono), I suspect I lost som top end by going directly to the autoformer volume ( 3m cables ) The dac I use does not have an output stage just simple I/V conversion. I have another dac where I have used Sowther trafos for I/V and gain. Will also try that.
Dont take my musings as final comments. Audio is a zig zag path.
@Soundhappy, I agree the M2 is currently more quiet than my F6.
@ZM slowness is without tube pre, only autoformer.
I had a good ( Unneccesary much gain) Leben pre&phono a couple of years ago but I exchanged the Leben for my current Altec A5/1505b horn setup. I got a pearl2 pcb but I might also built a tube phono stage. I will start by buffering the output from my boozehound phono ( pacific phono), I suspect I lost som top end by going directly to the autoformer volume ( 3m cables ) The dac I use does not have an output stage just simple I/V conversion. I have another dac where I have used Sowther trafos for I/V and gain. Will also try that.
Dont take my musings as final comments. Audio is a zig zag path.
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I got some B1 pcbs and components on order.first solve adding buffer in front of AVC
that's must
it'll solve majority of problems , and might save you from adding buffers all around
good for start
which B1 iteration , early one (2 x 2SK) , or later one (2SK +2SJ) ?
in any case , use smallest possible series output resistor , Papa's 1K was idiot-proof part, when you know what you're doing - just short it
hope Iron Pre kits will be available soon in Store , it is swiss knife solution ( selector , reg , buffers - everything on same pcb) and easily used in several configurations - pot + autoformer , just pot , or with AVC
which B1 iteration , early one (2 x 2SK) , or later one (2SK +2SJ) ?
in any case , use smallest possible series output resistor , Papa's 1K was idiot-proof part, when you know what you're doing - just short it
hope Iron Pre kits will be available soon in Store , it is swiss knife solution ( selector , reg , buffers - everything on same pcb) and easily used in several configurations - pot + autoformer , just pot , or with AVC
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Hi,
I've had my M2 since ~2012. Many times I've considered building a PP 300B...and then I listen to my amplifier and wonder if the difference (not improvement) is worth the effort. I'm with ZM in that the M2 just sounds right to me. Though now that I have said all of that I REALLY wonder about the SIT-3...
Kindest regards,
Chris
I've had my M2 since ~2012. Many times I've considered building a PP 300B...and then I listen to my amplifier and wonder if the difference (not improvement) is worth the effort. I'm with ZM in that the M2 just sounds right to me. Though now that I have said all of that I REALLY wonder about the SIT-3...
Kindest regards,
Chris
I have several of the older VFET amps in good working condition (Sony TAN8550, Yamaha B2, Sony TA 4650) as well as a sample of the 20 watt Pass Sony VFET knock off (apologies and Mea Culpa to Nelson Pass, I didn't know it was controversial when I bought it).
VFET are very special, with their deep tone, black spaces and separation, but I can't say M2 doesn't bring it's own virtues to the table, especially the longer it is in service and seems to refine. M2 has become more defined and subtle with use. I don't know why this is, but I like it.
I can see how DEFISIT would be a reasonable direction, combining M2 type layout with a SIT in there. It would seem that it would get the organic with the spooky effect.
I'd like to hear the SIT 3 someday.
VFET are very special, with their deep tone, black spaces and separation, but I can't say M2 doesn't bring it's own virtues to the table, especially the longer it is in service and seems to refine. M2 has become more defined and subtle with use. I don't know why this is, but I like it.
I can see how DEFISIT would be a reasonable direction, combining M2 type layout with a SIT in there. It would seem that it would get the organic with the spooky effect.
I'd like to hear the SIT 3 someday.
No apologies necessary. I don't need to make any money on this stuff.
Vfets are now so scarce that we can smile at any example that makes
an amplifier.
I had 4x 10uf wima mkp10 250v caps, added them across the last C sin my M2 power supply so now I have CRCc ( 47000uf, 0R1, 47000uf, 10uf ). Really opened up the sound, 3d and dynamics. A singer that previously sounded wrong through my vinyl rig M2 and Slagels now sounded as she should. The M2 is now a lot less laid back through the Slagels ( autoformers) and sounds very nice through the Aikido linestage ( which adds some coloration of Its own of course).
Go figure?
Tested a buffer I had ( boozehound buffer - 2x 9v batteries) before the Slagle Volume. Slight difference, tilted the sound slightly i.e. more top and less bottom but added noise of its own. So there is some top end loss with the M2 due to impedance mismatch that I dont notice on the F6s.
Adding the 10uf had the largest effect, but I need to adress my sources to insure better impedance match. And probably give the M2 more time to settle.
Go figure?
Tested a buffer I had ( boozehound buffer - 2x 9v batteries) before the Slagle Volume. Slight difference, tilted the sound slightly i.e. more top and less bottom but added noise of its own. So there is some top end loss with the M2 due to impedance mismatch that I dont notice on the F6s.
Adding the 10uf had the largest effect, but I need to adress my sources to insure better impedance match. And probably give the M2 more time to settle.