it's written here http://www.diyaudio.com/forums/clubs-events/106844-burning-amp-festival-audio-happening.html , while Pa mentioned something about testing them , in his lecture
Um, so we need 4, no longer made SemiSouth R100's per amp? Am I reading the circuit correctly? Is there an alternate production part we can use?
hm....asked Paul from Linear Systems via email if I could buy a low quantity of lsk74. No concrete answer yet, which indicates it could still take some time..
Guess the market demand is too low for that parts (audio market is low volume), so there is no business case for linear systems to make those parts !?
They've been saying this for years. They make the LSK170 though. Why would they not make the complimentary part??
I guess I will hunt for some more Toshiba parts. The F6 schematic says IDSS=8ma. I think that works well in the F5 too. If I can't find 8ma IDSS parts, anyone know If I'm better off with something a little higher or lower?
"F6 Buffered" Does this mean there's more than one F6?
Yes - its worth listening to nelson's presentation posted earlier up. The non-buffered version doesn't have the input jfets but you can only drive it properly with a preamp having very low output R. There are a few different versions of this that you could build to suit your tastes/needs - fb, no fb, input jfets/no input jfets, source resistor+distortion modulation pots across Rs...very interestingly, Pa sez you get more (80% thereabouts) of the power in class A without the source Rs (ie slide 13 version)
That's the one in ZMs post and I'd guess this to be the 'standard' base model. We can wait for the article for the fully monty ....
I have a few fish to fry while waiting
Yes of course you can use different Fets.. this is a really versatile platform, a real experimenters amp if you like. I had a version of this up and running with hitachi lateral fets (2sk1058). Just a few notes if you want to use different fets:
a) swap out the leds for a 5v or so zener (most of the other fets need a higher bias voltage cf the R100s)
b) unless you add temperature compensation, stick to lateral fets (tempco can probably be handled by a thermistor across the bias pots ala F5)
c) lateral fets have much lower transconductance than the R100s so fb resistor may need to be increased.
Hope this is helpful....
tea-bag got about ninety SS R100, PM him....
if tea-bag can not serve you, PM "Sonorous129" ,Roger, he has still about 60-70 SS R125 he will probably sell, for reasons unknown he his not interested to offer them by swap meet, but he is open to sell on demand....
Trying not to be too commercial here - I have waiting list for 52 of 90. They are two different lots that Newark sent, so be a lot of 50 and one of 40.
I have asked Roger if he will sell me the whole lot of the R125. That might keep the F6 production going a little longer, and I can match them up best as possible, so less waste.
I have been researching leads for other sources of R100's as well. The supply is bleak for them too, but they were actually used for other purposes. I will need to sell these first to get cash for the next round
I have asked Roger if he will sell me the whole lot of the R125. That might keep the F6 production going a little longer, and I can match them up best as possible, so less waste.
I have been researching leads for other sources of R100's as well. The supply is bleak for them too, but they were actually used for other purposes. I will need to sell these first to get cash for the next round
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tea-bag got about ninety SS R100, PM him....
if tea-bag can not serve you, PM "Sonorous129" ,Roger, he has still about 60-70 SS R125 he will probably sell, for reasons unknown he his not interested to offer them by swap meet, but he is open to sell on demand....
Thanks for the heads-up generg...i contacted both last week
C
hello F6 sleeve 13 fans.....
I am not really good in distortion measurement (dsdjoy is much better) but astonishing at 8 Ohm and 1 Watt and Jensen I have with my Frankenstein 6 build besides k2 and a bit k3 nearly no higher harmonics, I did not see this often.......
I am not really good in distortion measurement (dsdjoy is much better) but astonishing at 8 Ohm and 1 Watt and Jensen I have with my Frankenstein 6 build besides k2 and a bit k3 nearly no higher harmonics, I did not see this often.......
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Yes! Very helpful and I really appreciate you sharing your insights I will be the first to admit I have lots to learn. I can use all the help I can get!
Thanks and kudos to generg and Tea-Bag also for your replies. That's what makes this site so good! Folks helping folks.