Beresford Bushmaster DAC Reviews

[lurcher]

Yep Stan, thats the same supply design that I am just finishing off now. Should have it ready to go to the first person who wanted a play by the end of today. At the moment I have it at 13.5v, I will do some more comparisons and see if there is a sweet spot.

[The Vinyl Adventure]

I have me LDA PSU running now ...
My god this thing is good! There has gotta be some sorta voodoo going on here Nick!
Yums the man my man!
It's honestly like a breath of fresh air has just blown through my system ...
This is easily as big a step up in quality as the dac was in the first place...

Stan, Nick... Good work!!!
For a total of just shy of £400 I can't see how this dac/psu could be beatable for a serious amount of money!
I am absolutely blown away...
I rarely get this excited about this sort of thing, but I really wasnt expecting it to get this much better!!



Nick, if you find an optimum voltage will you let me know?!

[The Vinyl Adventure]

I've had to submit to the eastenders half hour now ...
So yeah ...
This thing basically takes what the bm does normally and literally sound as though it's put a rocket up it's ass ...
Still all of the same attributes but very much emphasised ... It's only downfall is it takes it further away from what I was used to and is goin to mean I'm gonna have to get used to it all over agin ... I don't think for a second that it's a bad thing mind!
Very impressive indeed

You got these on the site yet David?
Shall I do you a slide for the slider?

[MCRU]

I've had to submit to the eastenders half hour now ...
So yeah ...
This thing basically takes what the bm does normally and literally sound as though it's put a rocket up it's ass ...
Still all of the same attributes but very much emphasised ... It's only downfall is it takes it further away from what I was used to and is goin to mean I'm gonna have to get used to it all over agin ... I don't think for a second that it's a bad thing mind!
Very impressive indeed

You got these on the site yet David?
Shall I do you a slide for the slider?

Oh go on then!

Glad you like it, is it fair to say that Stan's latest creation and the LDA PSU transforms the DAC into the super league?

[DaveK]

I've had to submit to the eastenders half hour now ...

Hamish, be careful what you admit to on here about submitting to SWMBO, it's likely to get you a diatribe of criticism heading your way .
Dave.

[SteveW]

Hamish.. tell you what matey, you plug in headphones into the BM right now and you'll be a tad deaf for a while. !!

[RoboCopper]

Hamish, did you try battery? How it compares to LDA PS?

[MCRU]

Hamish, did you try battery? How it compares to LDA PS?

I did mention on another forum a while ago that this PSU is the nearest thing to using batteries, if you would like to know more about the design there is a paper that Nick has written, exert from it is below for anyone who is interested.

.................................................. .................................................

When thinking of regulation, it’s worth remembering the Roman god Janus. Who was the god of gateways, and was a two faced god looking in both directions. Likewise a good voltage regulator is required to look in both directions at once. From one direction you have the mains supply, with the ever increasing noise, distortion and random variation that exists on our household mains supply. In the other direction you have the device you are supplying power to. The load will be asking constantly varying current, and the job of the regulator will be to ignore the varying load and to supply a rock steady voltage that ignores the changing load.

To ask a single regulator to perform both tasks means that it can not do either as well as it could. We don’t ask our regulators to be two faced, we split the two functions into two separate regulators and put them both where they can do the best job.

The first regulator is close to the mains supply, its job is to take the incoming mains and convert it into a low(ish) noise DC supply, and to isolate the mess that is our household power lines from what follows. In most power supplies on the market, the output of the first stage would be directly connected to the load device, and that would certainly be an improvement over the supplies that most manufactures provide. But we can do better by adding the other face of Janus to the system.

The second regulator is supplied with a clean low noise supply, and its job is to handle the changing demands of the load. To do that, it needs to be as close to the load as possible. So we remove the second regulator from the main box, and place it close to the load, both electrically and physically, that removes it from the noise and interference of the mains supply, and allows it to spend its time looking towards the load. Typical commercial voltage regulator chips are general purpose devices, but are not quiet enough for the task on hand, so the second regulator uses a bespoke regulator based on a low noise multi stage filtered voltage reference, a low noise error amplifier and a high current low resistance mosfet. To allow it to handle the changing load it also needs to supply current on demand, so all the remaining space in the second regulator is filled with low impedance capacitors to act as a local energy source.

Using the two stages of regulator, we achieve a noise floor equal or better than most battery supplies, and a effective source resistance of the order of 0.02 ohm (and the short cable run to the load avoids increasing this valve by adding copper where its not needed, and the use of a discrete regulator design allows that tiny value to be maintained way above frequency any audio device operates at.

[The Vinyl Adventure]

Oh go on then!

Glad you like it, is it fair to say that Stan's latest creation and the LDA PSU transforms the DAC into the super league?

It's extremely impressive, that's for certain!

I've not tried the battery option ... I'm not sure I'll bother now!

[StanleyB]

I have me LDA PSU running now ...
My god this thing is good! There has gotta be some sorta voodoo going on here Nick!
Yums the man my man!
It's honestly like a breath of fresh air has just blown through my system ...
This is easily as big a step up in quality as the dac was in the first place...

Stan, Nick... Good work!!!!

Glad to read that you have increased your listening pleasure with Nick's power supply.

But without putting a damper on things, it's not the same power supply that Nick developed specifically for the Bushmaster. Nick built me a special power supply with an extra connection that hooks up between the earth terminal on the BM and his PSU. After I finished my own R&D, Nick has been fine tuning the design based on my feedback of my technical findings. Since then he has taken possession of a production version of the BM and put the finishing touches to his dedicated Bushmaster linear power supply. I mentioned a few post back that he was almost ready to release it.