Its DIY DVV, you can build what you want , space is there for what was suggested . turn the trans on it's side, layer tower style on the inside...
Go for it ....
I will, Wayne old buddy, don't you worry none.
My inital assumption was let's do this one right, and damn the cost. Logically, I am building a jet plane to go to the toilet, since my speakers are a very easy load and are rather effcient, a nominally 50 WRMS amp will drive them to nirvana and back, but hey, who cares?
Also, I already have like 80% of the materials, I have a case of 20 heat sinks for high power dissipation, I have like 25 or 30 10,000 uF/63V capacitors, about 16 4,700 uF/63V and around 20 2,200 uF/63V capacitors, all by the German manufacturer Fischer & Tausche, in addiiton to some from Panasonic and a load of caps from A/V company of Italy. These are pure junk, but dirt cheap and a Godsend for testing and prototyping. A few hundred MPS small signals of all types, loads of BC types, 60+ 2SK170 FETs, tons of Wima (which I need for my line filters) and so forth - you get the idea. When you work it all out, I actually have around 70-80% of the materials, and the hard part to get - all I need are diodes and resistors, and you know how dirt cheap they are and how easy to get.
So, I can afford to go wild if I want to, I've paid the bill already. My priorities have changecd - my dilemma now is whether to mount all 8 one channel power trannies on one heatsink, or whether to use two such heat sinks in a monoblock package, whether to throw in an additional cooling fan which could trigger whet the heat sinks reach a temperature point, etc. Then, if I do, should I go for an El Cheapo fan, or buy a Papst all metal fan, with a life expectancy of 1 million work hours, but priced at just over $100 each?
Jeez, it's a hard life, isn't it?
Carmina Burana will require a lot more than 50 watts , as shaggy and bounty Killa ... for sure the swedes will need more .......
http://www.youtube.com/watch?v=H-3zov8UsJc
http://www.youtube.com/watch?v=H-3zov8UsJc
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Giving up one more secret of successful sound...
In my amps there is no difference between peaks and average. Power supply, headsinks or output tubes should deliver infinite time the peak power. Such a way dynamic distortions are minimal. It is one secret why audiophiles prefer SE amps. If to build PP class AB amps similarly they sound no worse than SE monsters.
In my amps there is no difference between peaks and average. Power supply, headsinks or output tubes should deliver infinite time the peak power. Such a way dynamic distortions are minimal. It is one secret why audiophiles prefer SE amps. If to build PP class AB amps similarly they sound no worse than SE monsters.
Modern, "crap"
pop recordings are good for testing this sort of capability ... they're compressed to billyo, which means that at 3/4 volume you're close to being deafened, continually; then the trick is whether one can adjust the volume up or down around this point with zero tonal changes ...Frank
Sustained Crescendo ...
On a serious note , the crescendo on some passages last for at 10-15 seconds. Choirs have away of separating the wheat from the chaff , not to speak of the 10 amp fuses letting go ... ..
Easy to do with those little "sustained" 20 watt monsters .....
It does not matter. My Pyramid amps have 2x100W output power. It's transformer is for 360W continuous, it is quite different from what you can find in that 7+1 "1000W" amps
In Tower amp I have 3x300W toroids.
Yes indeed they do. Choirs are very hard to do.
Sustained loud passages call for a robust power supply.
My speakers have to fill with sound a room of some 110 sq.ft., i.e. small. They are nominally 8 Ohms, minimum 6.5 Ohms, worst case phase shift is -25 degrees, effciciency is 92 dB/2.83V/1m.
My speaker cables are van den Hul Hybrid 352. That's a mix of silver plated OFC cable, mixed with carbon fibre (vdH has been a professor of metallurgy at a Dutch university for 40 years now). Cable has 2 x 256 strands and is capable of passing through well over 200 Amps.
My current range of readily available amps consists of cheap'n'cheerful low level (a bit above absolute entry level) 2x50W to very much High End 2x180W amps, from Toshiba, Marantz, Sansui, Harman/Kardon and Karan Acoustics ( http://www.karanacoustics.com ).
The point is not to go watt mad, I already have more watts available than I know what to do with. The point is twofold:
1. It has to be mine, I have to design and make it, for the hell of it, and
2. As John put it so aptly, it has to be done right.
At this time, I have a simulator working model which will nominally deliver 28.3 Vrms into 8, 4 and 2 Ohms, with minimal voltage loss, on a continuous basis. It will not clip up to around 175 W/8 Ohms, due to relatively high voltage lines, +/-63 regulated for everything including predrivers and drivers, and +/-56V for the output trannies alone. There should be two versions.
One should use 3 pairs of Motorola/ON Semi MJ 21195/21196 (metal can TO-3 trannies, rated at 250W each, 15 Arms, 30 Apeak, Ft > 4 MHz).
The other should use 4 pairs of Motorola/ON Semi MJL 3281/1302 (platic pack TO3, rated at 200W each, 15 Arms, 30Apeak, Ft > 30 MHz).
The two versions have a double purpose. One is to check out for myself a theory I have, which is that in many cases, older power devices, developed over decades, actually sound just as good and often better than the new(er) ones, even if their spec sheet says different. I have a nagging feeling that older power devices appear to be more stable than the new ones, and I want to check it out.
The other is to produce two solid power amps, which I can then use to biamp my speakers. If it turns out as well as I hope it will, perhaps a third unit later for the wife, who currently has a Harman/Kardon 680 integrated powering her JBL Ti600 floorstanders.
That's it in a nutshell. No binding peconceptions, my starting point is a fully complementary topology, but I do not insist on it.
The only thing I do insist on is fully electronic protection against overvoltage, overcurrent, overheating and excess DC. I do not trust fuses alone, I've seen far too many burnt out amps with "protection" fuses intact. I believe the fastest fuse we have is one made up of transistors.
That's it.
It does not matter. My Pyramid amps have 2x100W output power. It's transformer is for 360W continuous, it is quite different from what you can find in that 7+1 "1000W" amps
In Tower amp I have 3x300W toroids.
Yes, and in the last few years, the Chinese have come up with "PMPO", or "Peak Modulated Power Output". That's a magic formula which enables their say desktop PC speakers, fed from a teeny meeny 20W outboard power supply to enable them to deliver literally hundreds, and sometimes even thousands, of watts.
Tesla must be turning in his grave.
I am thinking either about one 1 kVA toroid, with separate secondaries for left and right, or two 500 VA toroids.
When I was 14 I remember taking music power calculations to my science teacher Mrs Grundy . She convinced me that peak current x peak voltage the only meaningful calculation . As far as I know she had never considered the problem before . You should have seen her . The blackboard was covered in maths just like a spy film and she was on a voyage of her own . I asked how she could be so confident ? She had worked on radar during the war and it reminded her of similar things . She drove an orange VW Beatle . She was way beyond eccentric . I remember congratulating her on my grades , she said she had asked for me to be marked down due to my extreme laziness . I wasn't allowed to go on BBC Young scientists of the year as my hair was down to my waist ( I suspect other reasons also ) . I didn't mind as it was an embarrassing project . Still liked her , DF 96 are you she ?
Many people have said many strange things about me, but I have never before been suspected of being an ancient female schoolteacher. Each part of that is wrong: I am not quite ancient (although not far off), I am definitely male and I have never been a schoolteacher.nigel pearson said:
It is for others to judge whether I am eccentric. I do like maths and I do like truth - perhaps nowadays that makes me eccentric.
Unfortunately for all of us, it does.
Disclaimer:
I do NOT think of you as eccentric, just precise, and I respect precise.
I do NOT think of you as an auncient female schoolteacher, or even just a teacher, at all.
Just for the record.
It does not matter. My Pyramid amps have 2x100W output power. It's transformer is for 360W continuous, it is quite different from what you can find in that 7+1 "1000W" amps
In Tower amp I have 3x300W toroids.
Only 3 300W toroids?
I expected at least three Chernobyls.
It was the previous one. The last one was never finished, it stays in the corner waiting for the winter.
Winter? Really?
Do such bad things happen in the promised land of California?
But seriously, I really cannot imagine winter in California. Somehow, after so many movies from Hollywood, we who haven't been to California imagine it in a perpetual summer. "Winter" seems like just a little less summer.
Do you EVER have any snow, even if transient?
Sorry about my strange and sincere compliment . Of people I have taken notice of you and she start to fill the fingers of one hand .
Thanks for polynomial distortion fact . I work around it as best can and with greater success since you said it . Truth , I say fiction is the only truth . It often contains truth and makes no pretense of being the truth . Liking the truth makes you eccentric ? That seems to have the ring of truth about it ?
Nigel
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