I've got a couple of these little tekdevice regs and whilst they seem to work nicely, I have no doubt that something like a Tentlabs Shunt regulator is far superior in terms of providing for a dynamic load.
The reason the Tekdevice ones are cheap is because they only use a single TPS7A4700 chip which costs £5 plus 4 x SMD capacitors. It states it's low noise and the figure given of 4.17-μVRMS is very low, but that doesn't really tell all of the story....
I've put 1 of these in 3.3v flavour (you can easily change the voltage output on these by bridging the jumpers on the board btw) on my mainboard, mainly because I've bypassed my power supply resistors, so my 12v supply will be dirtier than Doede intended.
Hi,
So here are the pictures of my new power supply. It's quite elaborate so I needed to rearrange the complete layout. I put the wave IO on top of the Pi, I still use two streamers, the Alix and the Pi; Alix through Wave IO and Pi I2S connected. I like the Pi more. Just waiting for Russ White to release the cape for the BBB.
On to the supply: on the left side there is a big 200VA transformer (sec. 2x12V), a friend of mine had ordered these specially manufactured to order for use with other Dacs and CD players. This is a really awesome transformer!
It is a simple CLCLC supply using two Silmic 2200uf caps parallel and Lundahl filament chokes.
This supply surpasses all supplies I have used up to date, including the one from Bernd during the visit at Klaus!
It's been a long time since I had so much goose bumps listening to music
Advantages: dynamics, openness, forcefull, detailed, more space, did I mention dynamics?
This one will stay for sure!
The Salas supply is for the Pi and Wave IO.
Regards,
Very cool Stefan
I have to try it!
Am I correct that you're not regulating the voltage at all with this power supply? So 12v AC becomes somewhere around 17v DC?
So it's very low impedance and nicely smoothed, but the actual voltage can fluctuate a little. Sounds like the ideal power source for small local regulators
+1Very cool Stefan
Sounds like the ideal power source for small local regulators
Lundahl says "voltage ripple is approx 0.42*input voltage", but dont know how much does the second choke and caps smooth it...
Thanks James for shedding some light on that subject.
If I think how far this single deck DAC has come along just by supplying the DC as cleanly as possible, it makes me wonder what level of improvement is still to be gained from stacking up the DAC chips in parallel. This is why i'm interested in comparing the local regs against global super regs.
I simply don't want to spend the £1000 it would cost to shunt regulate 8 decks so researching the £250 approx. option of 5 super regs is of interest to me. I'd be very surprised if the shunted decks turn out to be 4 times better than with the super regs, but then how do you go about measuring such a thing. It's entirely subjective. All I know is that my hifi is sounding better and better by the day.
You're not far from me at all, give a shout when you've got stuff together and we'll do some direct comparisons
No such thing as LDO shunt regulator
Shunt regs are the opposite: HIGH drop out - they require voltage to burn to maintain a constant voltage. That is why they generate heat and why in a small package I worry there is not enough margin (temperature) for them to act as a classical shunt regulator.
I think they cut it close so if there are large current demands they will not be able to supply and if they are required to output more than the average they were designed to supply the regulation at that point will be poor.
All is compromise ...
Those regs in question are series regulators.
Shunt regs are the opposite: HIGH drop out - they require voltage to burn to maintain a constant voltage. That is why they generate heat and why in a small package I worry there is not enough margin (temperature) for them to act as a classical shunt regulator.
I think they cut it close so if there are large current demands they will not be able to supply and if they are required to output more than the average they were designed to supply the regulation at that point will be poor.
All is compromise ...
Those regs in question are series regulators.
@ James,
I get around 16v of raw DC, than the Lundahls drop 2v each and everything comes out nicely at 12v. It is completely unregulated.
This is indeed the perfect low impedance supply I was looking for. The ripple is very low and small fluctuations due to wall Ac fluctuations are all within the regulating range of the tent shunts.
Chokes have a clear advantage over resistors or series regulators.
The main advanage of this type of supply is the low impedance; this makes the dac really sing.
In my tube amps I use 4 chokes in a row for super smooth DC, and also without regulation. I also experienced similar behavour in my tube amps when I tried series regulating, than shunt regulating and ended up with unregulated choke supply as the best sounding option.
@Thommy,
Why would it be less important using a good power supply regulator on the mother board than on the digital side of the dac? They both handle 1s and 0s. And by now we all know that there is a lot going on in the digital domain (jitter) that influences the data stream.
It even matters when powering a clock unit, good shunt regulators have proven lower jitter in these situations.
I use shunts everywhere and on all positions I noticed improvements, but I must say the shunt effect is lowest on the mother board shift registers
The tekdevice regulators are series regulators not shunts.
Regards,
I get around 16v of raw DC, than the Lundahls drop 2v each and everything comes out nicely at 12v. It is completely unregulated.
This is indeed the perfect low impedance supply I was looking for. The ripple is very low and small fluctuations due to wall Ac fluctuations are all within the regulating range of the tent shunts.
Chokes have a clear advantage over resistors or series regulators.
The main advanage of this type of supply is the low impedance; this makes the dac really sing.
In my tube amps I use 4 chokes in a row for super smooth DC, and also without regulation. I also experienced similar behavour in my tube amps when I tried series regulating, than shunt regulating and ended up with unregulated choke supply as the best sounding option.
@Thommy,
Why would it be less important using a good power supply regulator on the mother board than on the digital side of the dac? They both handle 1s and 0s. And by now we all know that there is a lot going on in the digital domain (jitter) that influences the data stream.
It even matters when powering a clock unit, good shunt regulators have proven lower jitter in these situations.
I use shunts everywhere and on all positions I noticed improvements, but I must say the shunt effect is lowest on the mother board shift registers
The tekdevice regulators are series regulators not shunts.
Regards,
@rickmcinnis
Thanks for the clear explanation. I guess that in this instance those shunts aren't being asked to do a lot in terms of their capacity and therefore are going to give a superior result to the series regs, as is to be expected considering the extra cost.
@supersurfer
I guess it's my opinion that the money spent regulating the mainboard shift registers is maybe better spent elsewhere in terms of price/performance ratio. Your own observations appear to reflect this opinion as having at least some practical basis.
I could put more expensive regs on that part of the board but replacing the I/V resistors would likely give a bigger improvement for similar outlay.
I was attracted to the DDDAC because it is affordable. Having now spent £360 total on my single decker, and with £550 worth of parts waiting here for the second build I am pushing towards £1000 spent on DACs and want to be sure that my spending remains wise.
Thanks for the clear explanation. I guess that in this instance those shunts aren't being asked to do a lot in terms of their capacity and therefore are going to give a superior result to the series regs, as is to be expected considering the extra cost.
@supersurfer
I guess it's my opinion that the money spent regulating the mainboard shift registers is maybe better spent elsewhere in terms of price/performance ratio. Your own observations appear to reflect this opinion as having at least some practical basis.
I could put more expensive regs on that part of the board but replacing the I/V resistors would likely give a bigger improvement for similar outlay.
I was attracted to the DDDAC because it is affordable. Having now spent £360 total on my single decker, and with £550 worth of parts waiting here for the second build I am pushing towards £1000 spent on DACs and want to be sure that my spending remains wise.
Excellent, and elegantly simple
It's nice to know that the theory translates so well into the performance of the end result. I definitely need to give this a go. Now that you've made 1 supply, is there anything you'd change if you were going to do it again?That was the best option I found if you're after the Audionote ones. The prices aren't always incredibly cheap, but Nick does a great job and is always friendly and helpful, so I'm happy to support him
I opted for the Rhopoint GG102 0.1% for mine after reading some good reports and I'm very happy with them. They were about £5+vat each.
Hi James,
I am starting over again with the dac boards. I just ordered 4 new boards. I will build these with silmic and will try some small mods but the rest will stay the same now, the tent shunts will move to the new boards. Next on the list is the streamer: bbb with TP cape.
I expect that the end result will be of top class!
If that is ready I will concentrate a bit more on a new speaker design using EMS field coil units.
The surplus 4 boards and mother board will be nice together with the Alix or Raspberry Pi for my hobby room
I am starting over again with the dac boards. I just ordered 4 new boards. I will build these with silmic and will try some small mods but the rest will stay the same now, the tent shunts will move to the new boards. Next on the list is the streamer: bbb with TP cape.
I expect that the end result will be of top class!
If that is ready I will concentrate a bit more on a new speaker design using EMS field coil units.
The surplus 4 boards and mother board will be nice together with the Alix or Raspberry Pi for my hobby room
The surplus 4 boards and mother board will be nice together with the Alix or Raspberry Pi for my hobby room
You don't say, I'm dreaming of a life where I can afford a 4 deck DDDAC per room (including the one with a throne
).No need to say I can't wait fot your thoughts on Silmic decks...