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Lengthy Time Constants for PSU's - Click HERE for Original Thread
iUSERTLO72p
Hi all,
I answered a post relative to the TNT website. Anyways, reading the article and others, (http://www.tnt-audio.com/clinica/preamble.html), I see there is a desire for the power supply to take along time to,
quote:
The time constant of the network at the gate of the MOSFET is in fact higher than 2000sec... that is, the units takes something like 3 hours to reach 95% of the final voltage
.

I have a car stereo running off a PC ATX supply, would a lengthy turn on , improve the quality of the supply, if I used a simple RC constant after the supply before the car stereo?

I figure the power supply to be a very important factor, and generally like to find ways to improve a power supply.

So, what can be done to create a quiet supply? Especially low power pre-amp circuits, crossovers, Linkwitz Transforms etc. How do you know when to use 1000uf of smoothing cap or 20,000uf :confused:

Cheers iUSERTLO72p:)
iUSERTLO72p
Okay, so what to do?
Search the web, as well as here? And find loads of various circuits, everyone claiming whats good and what ain't. I read TNT a few years back, and put "A Tiger in your amp", then got told elsewhere that your increasing distortion and lowering the Bias current was more sensible? Or something along those lines.
I just wanted the guru's in here to say, " Yep, use cap multiplier for class A, Jung for the digital stuff , batteries on yer pre..."

Would you say a battery is the smoothest DC? I'd like to get close.
I've read descriptions such as, " Dark background noise, no hash etc". Even Technics had their Virtual Battery circuit. So what I'm asking has probably been in a Thread somewhere, I did search, there's a lot of switched mode stuff and I found somthing like a floating capacitor or something, thats not connected to a mains supply.

So please, either give me some info, or can I have some words to put into the search box. Thankyou.

Cheers iUSERMike :bawling:
Eva
Car amplifiers and head units are intended to work with alternator ripple on top of the DC supply voltage without problem. The 12V line goes through a lowpass filter. Don't waste your time waiting for time constants 2000 seconds long... ;)
iUSERTLO72p
Hi, I'm also running a 24db Linkwitz highpass and lowpass crossover and a Linkwitz Transformed sub. I would like to know how much these circuits could be improved. I'm getting a 200w ready made module amplifier, and I will need to build a supply for it.

http://www.velleman.be/ot/en/product/view/?id=360356

What do you think?

Cheers iUSERTLO72p:)
AndrewT
quote:
I see there is a desire for the power supply to take along time to,quote:
The time constant of the network at the gate of the MOSFET is in fact higher than 2000sec... that is, the units takes something like 3 hours to reach 95% of the final voltage
.
..................So, what can be done to create a quiet supply? Especially low power pre-amp circuits, crossovers, Linkwitz Transforms etc. How do you know when to use 1000uf of smoothing cap or 20,000uf
the 2000S time constant sounds like rubbish to me.
Could it be a misprint? 2000mS or 2000uS?

On the second part, ripple can be used as a criterion.
1Vpp is commonly adopted in higher voltage PSUs when delivering maximum current.
Another useful rule is 2mF /Apk.

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