Building "The Wire AMP" Class A/AB Power Amplifier"

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Ok,
The last thread got strung out with the purchase of the boards and power supplies. Lets try to keep this one on topic with build info. First I have not decided to go mono block or stereo, my use will be for low end bi-amping with OB so mono blocks are not paramount as separation for bottom end is not a critical (some may argue). However this may not be the only application so versatility may prevail. In any case I will go with a linear power supply with a separate LME power supply. First off I purchased the low voltage regulator used on the wire headphone amps, I an having difficulties locating replacement capacitors with the correct voltage any suggestions? Second Owen recommended this for the transformer "60-50-0-50-60 @ 0.1A-7A-0-7A-0.1A with both 120 and 240V primary windings" I am not sure if that was for 1 or 2 channels. Also I have a couple of Brian GT's power supply boards do these seem appropriate for this application what capacitance would work if so?

Bill
 
Whats in the toy box now

Ok this is my plan DCB1 preamp or buffer, wire se headphone powered from dcb1 board, DSP module se in balanced out, LPUHP for full range may switch to F6 when available, wire A/AB for bottom end. Haven't decided on OB yet maybe Seas exotic or Lowther, probably divorce WAF on OB not good -low hide factor.

Bill
 

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nice!, looks like you have a few things that go 'bing' in the background there too. Whats the DSP?

I should have pics in the coming weeks too. obviously theres going to be some build related crossover posts from the switcher GB, but there is now a thread for directly dps600 related Q's as well in the PSU section. which has some preliminary pinouts and basic info AP2 posted a little while ago.

as for caps, you mean the main reservoirs? or just the ones on the FE regulated PSU? OPCs TX recommendation there will be for one channel, but you could in the short term use it for 2 if you kept the bias down, not a big deal if you are running it for bass. so go for 100V caps, pana FC are always good. I generally use screw term caps for main large reservoirs, so cant be too much help there, i'm sure someone or 10 will chime in with a suggestion, or 15
 
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MiniDSP

@ wirewiggler; that's looking like one impressive project...

@ qusp; the MiniDSP ... oodles of fun in a dinky package :)

I'm looking at the posibility of using the standard se 2x4 minidsp within a pre-amp to handle room EQ, and maybe x-over duties if I go with small speakers & sub setup [most likely XTZ & BK Electronics].

Bi-amping didn't cross my mind at the time of getting the pcbs, so yet another trick passes me by...
 
ahh, nah not for me, overflowing with dacs here, thought it was DSP only that I might not have seen. I nearly bought one to play ages ago before deciding to go all out on multiple sabre dacs. I posted a few non-standard implementation Q's on their forum and was met with silence, so they were passed by
 
My first thought was Mr pass's B4 but DSP offers some more flexibility probably at some degradation, but you need to find out for yourself if it is acceptable. I was was inquiring about both caps, My first look at Digikey I was unable yo find higher voltage offerings for the voltage regulator for the LME. Second question was about the reservoir caps I was wondering if these would be suitable http://www.apexjr.com/images/CORNELL12000UF.jpg . I am not sure what constitutes as a computer grade cap and if it applies to audio use.

Bill
 
well done DSP is unlikely to present more 'degradation' depends how you define it I guess. the thing i'm not sure about with the miniDSP is it resamples everything. look like good fun though and they do seem to be continuing to develop it.

pana FC are good, but I wouldnt bother with the output caps on the reg for the front end, if you are mounting close or directly to the amp, just omit them and leave it up to the ones on the amp. if its for the input, yeah these would do OK, I think 12.5mm is about as large as you'll fit on the board and I think 270uf is as high as they go in the 12.5mm P10781-ND at digikey. the stuff from Apex Jr should be fine, computer grade caps and industrial grade caps in general can be better than audio grade. I have some similar ones from him and theyre great.
 
If I go with the mentioned transformer applying the 1.414 multiplier using full wave rectification I will need at least 70v caps the cornell's are 80v they should work fine. At 3 X 12,000 uf + 1000uf local should be plenty. Will have to see what the duncan calculator comes up with.

Bill
 
Ok I have been slacking a little but it has been 107 degrees and the local pool has been holding more attraction than the garage. I had Richard at Sum R quote me a price and it seemed to good to be true so I double checked and I was right for a change (of course being right was not in my favor but years of marriage has hardened me). This is what he came up with "one center tap winding as you have listed below Sec # 1: 50 -0 -50 at 7amp.
Sec# 2: 60 -0 -60 at 0.1 amp Price US $ 122/e." \. All of my power supplies up to this point have been with dual primaries and for class a amps. I have been reading some of the power supply threads but have not been able to put it all together what is most practical for this application, any suggestions.

Bill
 
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I will be using an old kenwood power amplifier "KM106" as the chasis. Just about everything but the transformer and heatsinks will be trashed/recycled. I was able to pick up a defective "as is" unit on ebay for $25. I also found some small epoxied 15-0, 15-0 transformers that I can fit inside to provide the boost voltage. The original kenwood power supply was +/- 68VDC. I bought a working KM106 earlier for $50 and eventhough the spec sheet said 135 watts per channel, cliping occcurs around 170 watts. The working KM106 sounded not bad so I left it as is and gave it to my son.
 
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