# Aleph4 220uf voltage ??????? Anyone Yuhhuuu

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#### trigon

Hi.

It may have been posted earlier but I could not find it.

For Aleph 4 - 220uf I can't figure out the voltage, hope that
25V is OK, as I have very good ones but as I've mentioned 25V.

Is 25V ok???

Appreciate very much any comment.

Trigon.

Anyone????

Trigon.

25V is fine.

#### wuffwaff

Hello Trigon,

the two coupling caps are not so critical. I think even 6.3V will do here.
For the third one you can calculate the voltage from the 4k75 and 1k5 resistors and the 4-5volts over the transistor. 25 volts should be enough.

The only thing I don´t really like is the use of normal caps in these positions. I´ve ordered some BG NX caps (non polar) to use as coupling caps in my Aleph 5. I´ll see if things get better with those.

william

#### trigon

Hi guys.

http://www.diyaudio.com/forums/show...15&pagenumber=2

they talking about Aleph 5 which has +-34V rails, in my case I am building Aleph4 where we have +-48V rails voltage.

Yes I have 6pc of BG FK (top BG model) but they are only 25V.

Maybe Nelson can light us a little, we would really appreciate.

Thank you KINDLY.

#### wuffwaff

Hello Trigon,

25V is enough! Look at the voltages after the 4k75 and 1k5!

48v -4v is voltage over 4k75 + 1k5 so voltage over 1k5 is about 10volts. This gets even less when the DC bias resistor is added.

william

#### mefinnis

I used 25V in my aleph4 and there are no problems.

cheers, mark

#### Nelson Pass

Paid Member
Minimum value for the bootstrap caps on the current
source is 2/3 rail voltage, and the others can be 6.3 if
you like. In practice, I spec all the same part to keep
life simple.

#### trigon

First of all Thank you NP and everyone else whose trying to help.

After running cuple of analysis I came up with following.

Having BlackGate FK series caps 220uf 25V make me angry, just look the following picture from Circuit maker 2000.

Basicaly it will run close to the max. 24V!!!! Is this acceptable???

I am really greatfull to all of you guys for helping me solve this problem. I gues having 6pc of Black Gates FK 220uf 25V and questioning your self again and again "Can I use them in Aleph4" is really sad.

One more time Thank you kindly.
Trigon.

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#### trigon

OK.

I have decided to order a new 220uf BG capacitors. Now I've been thinking what would be the best choice of BG series to get for my Aleph 4?

Very gratefull, Trigon.

#### Peter Daniel

Paid Member
The best choice would be NH series non polar but since the 220u comes in 160V only and cost \$42 you might as well forget it. FK comes in 25V maximum, the other choice would be standard polarized which is 220/50 at \$7 a pc. I recommend you stay with FK 25V. If not, I would be interested in getting them from you for my Aleph.
The coupling caps are not really that important if you are not using balanced sources. I got good results with Panasonic HFQ 220u/25V, which I have at least a 100.
I wonder what brand are you using for source resistors?

#### trigon

Hi Peter.

If you think that nothing can go wrong with 25V BG I would gladly use those in my Aleph4. I am only scared that I can do more damage then goods.

As mefinnis has replayed that he has used the same BG 25v in his Aleph4 and plus you are recommending the same thing I may give it a try. Otherwise mostly still collecting parts.

Thinking of using Blue Panasonic 3W for source resistors , unless you have something better in mind.

Tell me how things are going in Montreal.

Trigon.

#### Peter Daniel

Paid Member
Montreal is a pretty European town with lots of night clubbing.
Go for the caps you have, because its hard to get any better. If they no good the worst you can expect is a small explosion inside your amp. I didn't say it before, but I once experienced it myself, the bad thing about it, it happened just into my eye and I carry an inplant from that time. I'm not kidding. So if I'm saying go for it you should not worry.

#### trigon

Peter.

Ooo Maaann. I am so sorry, I didn't know that. Dooughh.

But you know when I tried Circuit Maker 2000 I'm getting 24V on 220uf and on the other hand using Protel 99SE it shows me 14.5V on 220uf. That is basically the reason why I have to ask as many people as I can, who has tried and really measured it in live.

So if you really think that I can use them I'll go for it and use them. One more time as per Protel 99SE it shows 14V over 220uf.

Thank you Peter.

Trigon

#### AudioFreak

I think this might be a good time to heed the words of NP ... 2/3 rail voltage is 32V.

#### trigon

Hi AudioFreak.

It looks like. Yeap. 32V

Thanks.

#### Peter Daniel

Paid Member
Maybe Mark could measure it (since he built Aleph4).

#### mefinnis

My Aleph4 was a "concept" amplifier ...... ie. I did a lot on the cheap because I didn't know if it would all work OK ...... remember this was in the early days of Aleph ripping

I am in the middle of building a "quality" version of the Aleph5 which will be my living room amp. In the process of this I will need to take the A4 apart (those little inductors are just too neat to resist), so I will measure the voltage then.

My other comment is good quality caps can be run at their rated voltage quite happily, I don't think you have to have a 20-50% safety margin in DIY. If you can do this it is desirable and Nelson probably does for very understandable reasons! If you had very good caps at the voltage required then I would use these.

I'll send a post when I have measured the dV.

cheers, mark

#### trigon

Greatly appreciated.

Trigon.

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