psu configuration

[dog ears]

Hi Guys.:)

newbie rookie question.

wonder if you can help me please. i am thinking of building a stereo amp with 2 amp7's. probably running into 4 ohms. i want about 400 to 500 watts per channel.

however i am confused about the psu configuration and requirement.

am i right in thinking that what i would need is all three modules, psu1-ps/ss/vr? would this then be sufficient to drive the 2 amp modules in this configuration?

cheers.

ez

[dog ears]

whoops! just realized that the amp7 is a stereo module so i will only need one. amazing value. well done 41Hz audio. :D

[krilli]

OK the PSU1 boards are only one way to go about this, but yes, AFAIK they're a rather nice way of feeding your Amp7.

- First of all, you need an AC/AC transformer - you probably know this but yeah info can't hurt

1) The PS is necessary: It turns AC into DC and stabilises the DC
2) The SS is nice to have, bordering on necessary: It does some AC conditioning and provides soft-start (soft start at that power = probably good)
3) And the VR, yes, that would be necessary if you go the PS1 route - 5V and -10V are required, and this is the PS1 board that supplies them

There are other ways of doing this, also. For instance, I believe you can get all-in-one switchmode supplies that simply supply rail voltage, 5V and 10V out of a single box. Furthermore, you can also use a transformer with additional 5V and 9V secondaries and use simple regulators to make the 5V and 10V out of that.

But personally I'd go for the PS1's, or Audiophool's TBrick: http://maedos.com/Guideline.html#Building_a_Complete_Amplifier

[krilli]

... I have the feeling I've told you stuff you already know :)

[dog ears]

hey krilli.

thanks that's clarified a lot. that link is great.

ta for pointing out what seemed obvious - i had not been sure how conventional these supplies were.

at first glance it think that would go the psu1 route and with all 3 modules. good spec and they also look gorgeous too (important as i may fabricate my own see-through case with a nice think aluminium base [:p]

this amp is meant be an audiophile heavy weight, to integrate into my exising quality set up, to drive a pair of 18 inch subs (for when 'dog ears' wants to come out and play![}:)]

hey anyone, how good are the resevoir caps, as supplied with the psu1-ps, for audiophile work. also wondering if the standard 40,000 mfd is gonna be enough in my intended use? i think that the 18's will need a lot of current to control them??

dog ears.

[krilli]

Generally, as far as I know, 41Hz tend to use high quality capacitors. Top of the line caps, sometimes the next type below absolute top-end, from good large industrial manufacturers, often Panasonic. Nice, low ESR type of stuff. Can't comment on the capacitance value though.

[V-bro]

18"is often pretty high efficiency, thus don't particularly need much more buffer. 40000 is rather slim for one amp, but you can take two (like I always do...)

The quality of the PSU1-PS caps is rather great, not the absolute top but maybe a nail cut difference. They are very low ESR very high ripple Panasonic THA caps.... I buy them from a supplier for about 12 Eur. a piece. incl VAT. There are 20, 30 or even 50 Eur. a piece caps (or even more) that are a glitch better, but not by far in relation to the price. (perhaps just a few % better, adding another cap would completely overrule this advantage and be much cheaper after all)

------X-max. can be several meters on any driver, too bad it can be done only once...------

[dog ears]

hey thanks for your advice guys. just narrowed down the choice of 18'' driver i want, and they are only available in 8 ohm. having to have a rethink. perhaps a bridged configuration with a smps? weight and size are factors.

Ez

[abelma]

Hi....How to configure the Amp7, power stage, to choose the main voltage? It is the same procedure than the Truepath?
There is not assembly instructions..yet (?) to clarify this point. For example, I would like to use the Amp7 with +-50 Vdc.

[V-bro]

Same as Truepath basically indeed...

------X-max. can be several meters on any driver, too bad it can be done only once...------

[abelma]

Ok..there is a excell file to download where it explains the situation.