Hi guys,
It's been a while since I was last looked into DIY audio..
I recently picked up a dac with 5v power input. And often it's highly recommended to run this dac with a linear PSU. So I was gonna attempt to build one,
Requirements:
Output wattage: 15-20w
Output voltage: 5v
Output amps: 3-4amp
Quick noob questions:
- what would be the right toroidal for this?
- can I use off shelf PSU (ready assembled) and just add a transformer?
- any improvements over a custom built PSU?
- what size caps for PSU?
Thanks folks.. and merry Xmas..
It's been a while since I was last looked into DIY audio..
I recently picked up a dac with 5v power input. And often it's highly recommended to run this dac with a linear PSU. So I was gonna attempt to build one,
Requirements:
Output wattage: 15-20w
Output voltage: 5v
Output amps: 3-4amp
Quick noob questions:
- what would be the right toroidal for this?
- can I use off shelf PSU (ready assembled) and just add a transformer?
- any improvements over a custom built PSU?
- what size caps for PSU?
Thanks folks.. and merry Xmas..
Download PSU Designer PSUD2
Play around with it and be able to answer a lot of questions along the way yourself.
For a DAC you might want use a regulated supply. The 3-4A are pretty massive. Where does that number come from? Can you make sure if it really needs that much power?
When that is answered you can choose a regulator. There is a lot written about this and that diy or esoteric regulator design but there are a lot of really high performing regulator ICs available for ridiculously little money (like LF50CV) that will go a long way.
When you know the actual current draw you can spec a regulator and when you have chosen a regulator you can tell an input voltage to that regulator and start designing the raw supply.
Play around with it and be able to answer a lot of questions along the way yourself.
For a DAC you might want use a regulated supply. The 3-4A are pretty massive. Where does that number come from? Can you make sure if it really needs that much power?
When that is answered you can choose a regulator. There is a lot written about this and that diy or esoteric regulator design but there are a lot of really high performing regulator ICs available for ridiculously little money (like LF50CV) that will go a long way.
When you know the actual current draw you can spec a regulator and when you have chosen a regulator you can tell an input voltage to that regulator and start designing the raw supply.
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Go on Ebay and look up "Power One HC5". It's a 5V, 6A linear regulated supply - also available with overvoltage protection. May find perfectly good used ones for $10.
Power One and other similar products made by maybe half-a-dozen other manufacturers are available from 2V to 28V, with dual +/- outputs and at currents up to 18A (depending on voltage output). I've bought and used dozens of them for various amp/preamp audio projects - never had a problem. Their main use is in the machine tool industry and they can perform reliably for YEARS. Most are mounted on n "L" extrusion. Most have transformer primaries that can be wired for any mains voltage from 100 to 240VAC!
Power One and other similar products made by maybe half-a-dozen other manufacturers are available from 2V to 28V, with dual +/- outputs and at currents up to 18A (depending on voltage output). I've bought and used dozens of them for various amp/preamp audio projects - never had a problem. Their main use is in the machine tool industry and they can perform reliably for YEARS. Most are mounted on n "L" extrusion. Most have transformer primaries that can be wired for any mains voltage from 100 to 240VAC!
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Thank you, I will try our the app.
I wanted to build a PSU that can power the DAC, Chromecast audio, raspberry pi and portable HDD - all with one psu - hence the 3-4amp power requirements, more to future proof it really..
I was hoping that I can simply grab a toroidal with 5vac and plug it into a PSU similar to the ones available for chip amp.. would that even work?
I hadn't considered the regulation aspect until u mentioned it..
5VAC are 7VDC after rectification. If the smoothing filter is of the CRC type the voltage drop across that R (and therefore the output voltage) depends on the current draw.
Stellavox's tip is a good one. Get a supply like that and give every piece connected it's own regulator to decouple them and you have a lot going. Keep in mind that the regulator drops some voltage so you can't get 5V out with 5V in.
Stellavox's tip is a good one. Get a supply like that and give every piece connected it's own regulator to decouple them and you have a lot going. Keep in mind that the regulator drops some voltage so you can't get 5V out with 5V in.
A very simple and cheap way is a SMPS.
https://uk.rs-online.com/web/p/embedded-switch-mode-power-supplies-smps/1809368/
https://uk.rs-online.com/web/p/embedded-switch-mode-power-supplies-smps/1809368/
Do a search on the group buy for L-adapter, tea-bag is selling circuit boards and parts kits. You can set the voltage by sizing the transformer and setting jumpers on the board. It was designed by forum member Salas and if you find the original thread in amps - power supplies he has a build guide for it. I have built 3 of them one 19V for nuc computer, 1 12 V for mini dsp , and 1 5V for raspberry pie dac.
They work great.
Bill
They work great.
Bill
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These are quite OK. They are indeed sold under various names. No low drop but they are reliable.
I happen to have a very clean 1970-1980s era 5 volt power supply that was originally used in a university laboratory (I think the mylar foil asset number decal is from University of Michigan, but I got it from University of Minnesota). It has quite a transformer, possibly 20 lbs total. Let me know if you are interested in it; it's just taking up space.
Thanks guys, sorry for the late reply - new year festivities and all that..
the main reason i was looking into this was because I have a number of Toroidal Transformer 15V @ 30VA - I wanted to build something with these..
I guess I would need he PSU to be regulated.
How do I proceed using the above Toroidal Transformer? or shall i just stick with USB Phone charger -will i notice any difference in SQ?
the main reason i was looking into this was because I have a number of Toroidal Transformer 15V @ 30VA - I wanted to build something with these..
I guess I would need he PSU to be regulated.
How do I proceed using the above Toroidal Transformer? or shall i just stick with USB Phone charger -will i notice any difference in SQ?
If you want to use your transformer and go the DIY route, SMPS is the way. Search for buck converter lm2596 on eBay.
They're cheap and come in packs of 5 and do up to 5A each if cooled. You can of course use more than one and have several outputs.
They're cheap and come in packs of 5 and do up to 5A each if cooled. You can of course use more than one and have several outputs.
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Thanks Joensd..
I think I have a buck converter kicking about somewhere.
Do u think it's all worth building a dedicated PSU (linear or smps) when compared to say a 5v 2amp phone charger?
I think I have a buck converter kicking about somewhere.
Do u think it's all worth building a dedicated PSU (linear or smps) when compared to say a 5v 2amp phone charger?
I´m not a RasbPi-expert but understand the voltage has to be regulated and well within narrow limits and I´m sure there´s phone chargers that don´t work so well. But find a good one (or two) and you´re set.
You´ll find lots of 5V-supplies around.
Look at this fancy/expensive choice:
HiFi Power Supply | HiFi Sono DIY | Audiophonics - Audiophonics
If you´re comfortable to DIY you could indeed use your transformer, a buck converter down to let´s say 6-7V and then follow with a couple (up to 4) of low-drop-5V-regulators. That´d give you 4 separate outputs with exactly 5V/1A and relatively little power dissipation (well..)
Of course it´s work and the regulators, capacitors etc. cost money
so going DIY might or might not be economical.
I´m sure there´s lots of other solutions out there.
Have a look what you have on hand first.
PS.: Did you search here ? : https://www.diyaudio.com/forums/pc-based/
I´m pretty sure that topic came up. Otherwise try a RaspberryPi-Forum in addition.
Hey cheers again.. I was going to build it for my new topping dac that takes 5v. I read some mixed reports if a dedicated pay made any sonic difference when compared to a 5v phone charger..
Then look up/google what people use for their Topping DAC (here or somewhere else).
You are probably not the first one to question that.
Otherwise there seems to be dedicated RasberryPi power supplies
which should deliver a healthy 5V within tight limits:
Power Supply - Raspberry Pi Documentation
You are probably not the first one to question that.
Otherwise there seems to be dedicated RasberryPi power supplies
which should deliver a healthy 5V within tight limits:
Power Supply - Raspberry Pi Documentation
That would be an E30 or D50s or thereabouts, I guess?
In most cases, I wouldn't be expecting any miracles, assuming your phone charger has decently clean output and limited AC leakage and your audio cabling has decently low shield resistance - these DACs tend to have a tad more power filtering going on than a USB dongle. The optional Topping linear supply seems to be IEC Class I and as such may cause ground loop issues (bit of a *facepalm* moment right there - mind you, in some systems this may be exactly what you want, like when all you have is a laptop and a typical hi-fi integrated amp or receiver with some speakers and nothing else), so you'd generally want to go for a Class II compliant construction with the corresponding requirements on electrical safety.
In order to gauge the effect (if any) of the power supply, one would have to know:
* unless you are using Toslink input, what it is fed from and whether that is grounded
* what the DAC is run into and whether that is grounded and where.
In terms of power supply design, at 5 V I would be tending towards Schottky rectifiers and an LDO regulator design for reduced losses (lower secondary input voltage required), though with the few hundred mA of a DAC things should still be manageable even with everything being conventional.
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Hey sgrossklass
Thanks for the detailed response..
It is indeed a Topping D50S..
My setup is:
Flac > Raspberry PI > USB out
Topping D50S (usb connection)
Audiolab 8000P
Proac Studio 140mk2
I was previously using Musical fidelity M1DAC (dead on right channel)
I am just using an old apple usb charger with 1.8ish amps to power the DAC..
As with all audiophile stuff, I wanted to ask if anyone has tried and measured any real difference in audio quality using a dedicated psu.
Thanks for the detailed response..
It is indeed a Topping D50S..
My setup is:
Flac > Raspberry PI > USB out
Topping D50S (usb connection)
Audiolab 8000P
Proac Studio 140mk2
I was previously using Musical fidelity M1DAC (dead on right channel)
I am just using an old apple usb charger with 1.8ish amps to power the DAC..
As with all audiophile stuff, I wanted to ask if anyone has tried and measured any real difference in audio quality using a dedicated psu.
I always read the same things, dakku. "Night and day difference with a good dedicated power supply" - stuff like this. What I rarely see (actually never) are measurements that show the difference. If the sound is "night and day" different, then the measurements should be shocking.
Thanks for this topic.
Thanks for this topic.
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I ordered a board from AMB Labs. the single rail discrete power supply they have should be good. Topping also sells one for it for like $90 I think.