Real speakers aren't resistors and have a rising impedance at low frequency. I would not necessarily interpret the graph as meaning "worse bass". Have a look at some THD vs. Frequency graphs for pricey 300B amps.
With 101dB speakers you're probably fine as is. It's all up to you.
For those considering various iron-core inductors, this amplifier uses an air-core inductor to avoid saturation.
With 101dB speakers you're probably fine as is. It's all up to you.
For those considering various iron-core inductors, this amplifier uses an air-core inductor to avoid saturation.
Last edited:
so - any comment ...... or plan ?
you can try that with any proper mosfet , too ..... or smaller SIT
plain SE , parafeed , whatever .....
edit: shade-ed mosfet , too
Last edited:
lundhal has a 100mh C Core filament choke 3,4A (5,4 A saturation) , do you think it could fit the sit?
Aren't you the guy who doesn't want to use an inductor?
Post a part number.
I knew I forgot to do something. I'll will check it out tonight.
Tell NP not to post F5 Turbo and distract me.
...Some time back I played with the ZenV9 circuit using a big Hammond choke load instead of Aleph. Actually, I think it worked quite well. But, 1 thing that it did do that is somewhat of a problem is it made physical, vibrational noise with signal. It was a frequency/amplitude sesitive thing (maybe started around 3k?) but, quite audible. I believe they were spec'd well enough for this amp (3-5A, .64 ohm, 100+mH IIR)
You might never notice this phenomina unless you test with a resistor load. Have you noticed this problem? Can you hear your amp without any speakers?
I don't know if it's the E-Core Lams or the windings or? I wonder if impregnating epoxy resin into the windings will stop this or?...
Yea, that was a 5A PSU choke in the 195 series, I believe, w.64ohm DCR. I was probably doing 1.5-3A Iq. The trouble is the liniarity of the core. It is "metal" lams and it needs to be alloy bla bla or somethjing else designed for higher freq.s than 60Hz? And, empregnated with High tech resin stuff!
Looks way too small to me. I would expect a suitable iron-core to be a serious hunk of metal.
That's not unreasonable, close to 5lbs. The Hammond 193V is 150mH/3A and weighs 9lbs.
Roscoe
we ?
many moons ago , I made some prototype , brushed it a little and enjoyed in it
few months later , I paid dearly! for xeroxes of Sound Practices , and discovered that I wasn't first who reinvented ancient wheel ........ and that was just one of many humble pies I ate ( slow learner I am)
>>http://tinyurl.com/6svzvus<<
many moons ago , I made some prototype , brushed it a little and enjoyed in it
few months later , I paid dearly! for xeroxes of Sound Practices , and discovered that I wasn't first who reinvented ancient wheel ........ and that was just one of many humble pies I ate ( slow learner I am)
>>http://tinyurl.com/6svzvus<<
My intension is to upgrade my ZEN4 with the Sony SK82 KD-33 chip and dump the input buffer and go direct on gate on SK-82 with 47k to GND and some smaller Gate series resistance.
Using the Aleph current source gives a better Rout for normal loudspeakers, and the feedback will then be an option to play with...
There are also the voltage feedback to the regulator in the original ZEN4 design, it was for some reason not used in ZEN9, but I don't know why? Perhaps better leave it off?
Also the output voltage at 21-23V and supply at 42-46V seems a little high for SK-82, as the sweetspot was reported in the range of 13-14V and 2-3A?
Re-reading the ZEN9 article give me some second thoughts about my original plan. Seems like the Aleph-CCS gives better damping factor by raising the gain/feedback level, not by itself?
Meaning that a Aleph-CCS in a NFB amp would not lover Rout...?
So now I am leaning towards a ZEN4 set-up, where IRFP240 are changed but 2SK82 only...
Well, if we're being honest, there's nothing new under the sun really. But, there's still the pleasure of finding things out.
Even the late great Bob Moog wouldn't quite take full credit for his original thinking:
"I can feel what’s going on inside a piece of electronic equipment. I have this sense that I know, and to some extent, have control over what is going on inside the transistors and inside the resistors. When I am thinking about how to solve a particular problem I can think about it for days and weeks and nothing will happen. And, some day, when I am cutting the grass, or having a hamburger, or I wake up in the middle of the night, the idea will be there. I think it would be egotistical of me to say, “I thought of it”. What happened, is I opened my mind up and the idea came through and into my head. These ideas, I don’t have to dig up anything. Sometime I don’t even have to be thinking of them - and there they are.
It’s something between discovering and witnessing."
Bob Moog
Nice preamp, BTW
well , I think we are lucky to have here - expert for field of Mechanismus of Science Thought - Mighty Pa ....
while someone is reading sweet & nice literature , he's all in Science & Life humor books
(moi isa Expert for one special science branch - almost Copyrighted - Futile Attempts Method
)
while someone is reading sweet & nice literature , he's all in Science & Life humor books
(moi isa Expert for one special science branch - almost Copyrighted - Futile Attempts Method
)