Bimo,
I need to wait for someone to produce the boards for a group buy first. If all goes well after that I would need to find someone to produce them in some volume for my usage. Not sure what cheap means in regards to the NAD design and I guess a lot of this depends on the availability of the transistors used and the output devices, not to mention a power supply that will work well with the overall design. I need to keep the size of the transformer down so probably a toroidal transformer will be the choice. At the 70V range what size VA tranny that will be is another question.
I need to wait for someone to produce the boards for a group buy first. If all goes well after that I would need to find someone to produce them in some volume for my usage. Not sure what cheap means in regards to the NAD design and I guess a lot of this depends on the availability of the transistors used and the output devices, not to mention a power supply that will work well with the overall design. I need to keep the size of the transformer down so probably a toroidal transformer will be the choice. At the 70V range what size VA tranny that will be is another question.
The OPS is 75% cost , IPS 25%
USD ...
OPS = 40$ - 80$ , depending on 3-5pair and voltage/component quality.
IPS = 15$ CFA-X up to 25$+ for wolverine/spookeyamp. NAD-H would
be about 20$ (current mouser pricing /medium quality).
Estimates.. but close .
( I have to look up many devices- lead spacing/size info for layout).
OS
I am stressed ...
Now I know why I never designed a VFA symmetrical leach type amp.
It's like laying out two CFA's !! Multiple rail crossovers , "dripping"
with devices.
But I'll get it 😱 .
(Below)... down to the only the LTP's . WOW !
I know why the HK990 leach- like front end was all SMD and why
the Leach V4.5 was on a 5" X 5" pcb (125 X 125mm).
OS
Now I know why I never designed a VFA symmetrical leach type amp.
It's like laying out two CFA's !! Multiple rail crossovers , "dripping"
with devices.
But I'll get it 😱 .
(Below)... down to the only the LTP's . WOW !
I know why the HK990 leach- like front end was all SMD and why
the Leach V4.5 was on a 5" X 5" pcb (125 X 125mm).
OS
Attachments
Thanks for the pricing estimates OS. Like you said it must have something to do with available parts and quality level you chose. It does sound reasonable but there are other parts of the final implementation that also have to be added to those prices. Great responses though.
Consider this .... The "slewmonster" 5-pair + this "spookyamp" I'm on now
is the more refined/ heavy duty equivalent of the 2599$ harmon/
kardon 990 - minus the DAC's. (real close... CCS's and all)
With 21193/4 or MGxxxx OP's and our overbuilt "Anal" DIY PS's ,
it would most likely outpower AND outperform the HK by a pretty good margin.
AWESOME bargain !! 😀
OS
Tuned the "spooky" servo ... LF champ !!
.9mv offset and 9ppm from 10HZ to 60 HZ. NO other IPS does this good
in the LF range. Amps with a DC blocking cap "poop" right out under 50HZ
with a hefty rise in THD.
NOT the case here ... even (quite) better LF than the NAD-H.
OS
.9mv offset and 9ppm from 10HZ to 60 HZ. NO other IPS does this good
in the LF range. Amps with a DC blocking cap "poop" right out under 50HZ
with a hefty rise in THD.
NOT the case here ... even (quite) better LF than the NAD-H.
OS
Attachments
I "stole" the HK990 servo ... 😱
They used a 1meg X2 /1uF X2 2 stage filter for their servo.
I went with 680K X 2 /2.2uF X2 to get my .1-.2 HZ LPF.
"Spooky" is different than the NAD-H , it "servo's" the NFB node AND
it's a VFA. VERY accurate .. 🙂 (below)
OS
Attachments
Man it is hard to keep up with you OS! You have a new better design every couple of days. Still no patent issues with any of these versions? I thought that the original premise was that the CFA's had the more natural sound of all of the amps? Since this will only handle the mids and lows I don't need to worry about air on top with this section. I do want to drive the speaker down to the 35hz range and that is going to take an amp with great bottom end power.
hey OS, aren't you afraid that someone else copy your designs and use them for commercial purposes?
a few posts back, someone suggested that you edit your post#1 to consolidate your designs in that first posts, are you up to it?
a few posts back, someone suggested that you edit your post#1 to consolidate your designs in that first posts, are you up to it?
Patent ! 😀 sheesh! That is a simple standard non- inverting servo ," prior art" everywhere. I just referenced how HK implemented it.
Their (HK's) whole amp might be (...prior art -legal speak) , but not my
"blend" of 3 or more classic amp designs (basic, well documented building
blocks).
As far as low frequency reproduction - VFA's rule. I personally would choose the (soon to be
released)- VFA.. "symasui" as my subwoofer IPS.
OS
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Nah .... I researched , If they are in this thread .... I have "prior art".
IF I see any of these on ebay , I can DMCA takedown that listing. Let em'
try it ... I'll nuke um' 😀
I did edit my #1 post (in text) , all projects are listed by post #.
I wish 😎 I could edit the attachments , but this does not work.🙁
PS - of course ... if they were technical in any way ,
they could just change a couple components
and it would be "theirs" ..
OS
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thanks, OS, i reported your last post and maybe admins can look at it....😀
as you know, i wanted to do a 500 watt into 1 ohm amplifier using triples, so i will be borrowing a lot from your designs...
as you know, i wanted to do a 500 watt into 1 ohm amplifier using triples, so i will be borrowing a lot from your designs...
AJT,
I would just offer OS a royalty or something like that, I wouldn't steal anyone's idea like that.
I would just offer OS a royalty or something like that, I wouldn't steal anyone's idea like that.
Some Ebay sellers would .... 🙁
Actually , compared to some of the junk designs they sell - they would be in "cookie" heaven...
OS
I have talked to OS and my application is commercial. I am very honest with anything I do, just not worth stealing from someone, not my style. At the same time I am just a small fry right now, who knows about the future. It is nice to take people along for the ride when you can.
Just a thought but ...
If a group buy of PCBs was organized a 'royalty' for OS could be folded into the cost. He certainly deserves it.
If a group buy of PCBs was organized a 'royalty' for OS could be folded into the cost. He certainly deserves it.
I bought some of Lazy Cats boards and I think he was making a small amount of money, it was a fair trade for what he was offering.
Yes , the "cat" must be "stroked". He was the one of the members
that got this whole CFA thing a' rollin' 😀
OS