Glad you like the V9 regulator, Barry. It's a big difference from the V8, bigger than all the changes from V1 to V8 together. It should make the sound less dependent on the quality of the Raw DC, as well as some other useful updates.
May be worth trying the FT-3 (or FT-2) with standard resistor filament bias (rather than diodes) to balance the effects out - using parallel non-inductive Mills MRA12 resistors, or non-magnetic Ohmite AG10.
I agree with Rod - use resistors rather than SIC diodes. They always gave me a slight edge to the sound. It was better with combined SICs and resistor to give some feedback, but even then it's better to take them out completely. I have around 100 doing nothing.
The FT-2s are completely neutral for me, no edge to the sound at all, just plenty of transparency and detail.
The FT-2s are completely neutral for me, no edge to the sound at all, just plenty of transparency and detail.
I've been swapping between FT3 & Miflex recently, they are both very detailed, the Miflex has nice timbre, piano sounds amazing & has a bigger soundstage with acoustic instruments sounding very addictive, the FT3's are definately quieter than the Miflex though, I think they might be suseptible to RF, whether that's down to the aluminium can or not, I'm unsure, I prefer the Miflex to Mundorf SIO too. I'll let the FT3's burn in for more time to see whether they improve much.
I've heard a Russian resistor being mentioned before, I think Rod or Ale mentioned it in some of our emails. Which one is it - is there a number/I'd similar to the Russian caps?
I've had the diodes in for a while now and have been liking them, I thought they were a slight improvement in clarity and definition compared to the resistors I was using.
I've had the diodes in for a while now and have been liking them, I thought they were a slight improvement in clarity and definition compared to the resistors I was using.
Running the diode string in mine too. Any time i have tested biasing with an LED vs Resistor i always seen lower distortion, and better high end frequency response. My 01A preamps response was flat as a board way beyond audio freqencies so it didnt matter there, but from memory it did show lower distorion when i tested it, certainly sounded cleaner to my ears, especailly in the low end.
They are quite large silver ones, I have used them in the past, I have a few different values, they all seem to be marked "C5-5-10", 5%, they are 10W, & are Russian Military. You can usually find them on E%ay. "Sovtube" in the Ukraine has the 51R ones at the moment, He also has them in 10R.
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Some are yellowish in colour, it's like a varnish used in manufacturing, when surching just put in "russian resistors", sovetube has them for £2.59 for 18, just looked them up, they are the ones for sure!
I think I was the person who "discovered" these resistors and passed on the tip to Ale and others. I've been using them for many years. It is indeed sovtube that sells them on ebay. You can ask him to make up a combination of any resistors you want.
https://www.ebay.co.uk/itm/400798945712?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
Usual values in 10W are 1, 10, 27, 51, 62, 360, 620, 1.3K, 1.8K, 2.2K
https://www.ebay.co.uk/itm/400798945712?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
Usual values in 10W are 1, 10, 27, 51, 62, 360, 620, 1.3K, 1.8K, 2.2K
I prefer them to the porcelain wirewounds from Ohmite and Welwyn. Haven't tried the others.
I've tried all accept the M resist ultra which I suspect is made by powertron but they're on my tweaked Martin Logan Odyssey sorry. Winner are the powertrons very smooth & clean, m resist supreme nice too but there's emphasis towards the highs
+1 using Sic string, no come back to resistors. No edge sound so look for the problem in other places. I'm using Ale's hybrid Mu-Follower & Rod Coleman regs. for filaments.
Instead of filament bias, I switched to regular self bias with a regular resistor bypassed with Wima DC link cap. The bypass cap does matter. But the DC link is super smooth and liquid sounding. No more worry about special diode string or calculating power dissipation in filament bias scheme.
I've compared SIC diodes to resistors a few times. Put them in, took them out, put them in again, tried them in combination with a resistor. I hear an edge which I can't live with. It's pretty clear to me. I listen mostly to classical music and opera so I absolutely have to have smooth orchestral instruments and voices. It may be the case that the difference is clearer with classical music. Can't comment on what others are finding, that's just what I hear.
I totally agree about the DC Link bypass cap - it's what I use when I don't use filament bias. I haven't yet tried the cap in ultrapath. That's the next step.
Hi Andy
Unfortunately not. Only read of your experience. Will order some to try.
The powertrons are a ear opener, when I bought them it was not that expensive but now the price is pretty high. Not sure how it would sound on amps but I would assume its got the same signature as on my XO cause the powertrons are in series to the signal input. Reading from your pass threads Im sure you would like this sound if it suits your system
Cheers