I can send you some PCB if you are interested .
I have some left over and would return all their support .
Thiago
Step Two is done.
Hallo Friends.
Most parts are soldered in now- today.
I have read Hughs lesson about Z-out of Amps.
With experience in listening with a KT88 SE Amp i would say a lower Z-out- is
lower damping to speaker it hath less control to speaker coil- it can longer swing out after impulse- less damped (controlled). I know i like that.
It hath it's own characteristic, difficult to describe- fuller with more background,
fuller natural- if you know how a big drum or organ (komplex) or brass in
real acoustic, without amplifying Technik sounds you can understand the different.
cheers Bangla.
Hallo Friends.
Most parts are soldered in now- today.
I have read Hughs lesson about Z-out of Amps.
With experience in listening with a KT88 SE Amp i would say a lower Z-out- is
lower damping to speaker it hath less control to speaker coil- it can longer swing out after impulse- less damped (controlled). I know i like that.
It hath it's own characteristic, difficult to describe- fuller with more background,
fuller natural- if you know how a big drum or organ (komplex) or brass in
real acoustic, without amplifying Technik sounds you can understand the different.
cheers Bangla.Attachments
I just installed another brand of IRFP240's in my quasi. Actually did it to test if they were genuine and they are as they work well. Sounds very good and only $0.80 ea. Anyhow, the side benefit is that my previously bottomed out zero DC offset adjustment has improved. I now have range and can get down to zero offset perfectly with room on each side. Somehow the balance between the IRFP and the BJT is different now. Anyhow it worked out well. Amp sounds fantastic by the way. Had it out for a while and now back in and listening. Lovely sound.
Hi Thiago,
I'm lucky enough to own a AKSA 55N, even though this amp normally use 0.47ohm as emittor resistors I have used 1 ohm to great success, it is actually the best sounding amp I own. My powerfull VSSA is now collecting dust in the closet. Looking forward to soon build the Quasi.
BR,
Eric
My peeceebee vssa also on this side . Bass very dry.
tomorrow I will try to mod resistance 1R .
this week I'll be sending your PCB , sorry for the delay.
Regards
Thiago
tomorrow I will try to mod resistance 1R .
this week I'll be sending your PCB , sorry for the delay.
Regards
Thiago
No problem Thiago, much appreciated !
I did not order my components yet so please report back w the 1R mods ;-)
BR,
Eric
I did not order my components yet so please report back w the 1R mods ;-)
BR,
Eric
The fact that a device works is not proof that it is genuine. That's like saying I bought this '59 Porsche. My mechanic friend tells me it is a kit car but I think it is actually a genuine Porsche because it got me home from the used car lot.🙄
If you read the thread in fake transistors - the fakes all invariably use a puny transistor encased in a big fat power transistor body. So your analogy would be the fake Porsche will barely go past 25 mph before the engine blows up. Maybe fake/genuine is wrong word. Fully functional equivalent - is more like it. If the kit car goes just as fast and lasts as long as the real Porsche - I don't have a problem with fact that it's not really a Porsche. My next thing was to take a vise and crack off the epoxy. But since it works and the member Eva's famous test for "fakery" is to use an AC capacitance measurement. Measure capacitance of the gate to supply and compare to real. A small puny die will have lower capacitance than a real one. Basically a way to have X-ray vision of the die without cracking the epoxy off. These particular IRFP240's also passed the Eva test.
Here is photo of the fake 2SC5200 vs real. Fake is tiny die encased in white RTV. Real is bigger and no RTV.
You can see why capacitance is different and gives clue of genuine die size.
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I think it's
Still4given: I won't use anything but a transistor from Digikey/Mouser/Newark because all stuff from Aliexpress or Ebay is fake.
xrk971: I won't buy a transistor from Digikey/Mouser/Newark if I can get it from Aliexpress and it works.
Fact is, we both seem to be able to build lots of amps and they seem to work for us. So maybe there really should not be any disputes really. I have one case of fakes and got a refund. About 40 bags of trannies from Ali that are good vs 1 bad. Pretty good odds.
Unbelievable.. I'm as frugal as the next guy.. likely even more so 😱
But there's NO imaginable scenario in which I would even buy,
let alone use an 80 Cent ! irfp 240.
When Mouser sells Genuine ones for.. say What ? 4$ each 🙄
This is real life .. one Cannot cheat an honest man.
But there's NO imaginable scenario in which I would even buy,
let alone use an 80 Cent ! irfp 240.
When Mouser sells Genuine ones for.. say What ? 4$ each 🙄
This is real life .. one Cannot cheat an honest man.
Digikey has them for $2 and 9240's are $2.50. I agree it's probably not worth the risk unless you are buying a bag of 10 or more. I buy half of mine from Digikey mainly for fact that it's fast and when you run out you need more in a hurry.
Not sure what being an honest man has to do with getting cheated. Are you saying people who buy from Aliexpress who get cheated are dishonest? Well that's utter nonsense.
Not sure what being an honest man has to do with getting cheated. Are you saying people who buy from Aliexpress who get cheated are dishonest? Well that's utter nonsense.
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These are made in China, but then, Fairchild do most of their work in China too. I use the FQA series, and they are very cheap. A couple of years ago I bought 500 FQA3615 for $AUD2, which is presently around $USD1.54. Not bad for a 280W pmos!
Yes, Bare, how can we resist the Chinese prices? They will wipe the board..... no jobs in manufacturing for our kids......
Hugh
Yes, Bare, how can we resist the Chinese prices? They will wipe the board..... no jobs in manufacturing for our kids......
Hugh
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