Joshua_G said:
Thank you for your ideas. For me it makes no sense to use a shunt regulator, when it is followed by series regulators, but I think it is best to wait for the experts.
Of course it seems to be overkill to use a Placid just for left and right analog supply.
And you are right, at least we should try a Placid for the digital supply as well and even remove the 3.3v regs, but now I am going too far...
André
Joshua_G said:
When I first made up the buffalo I noticed a clear improvement when I modified the 1st supply upstream to the on board regulators. I would interested to see what better on board regulators would sound like. When thinking about regulator noise I think a good question to ask is - how much of the noise present at the regulator output comes from the internal circuitry and how much gets relayed from the supply lines. I believe the answer to this question explains the benefits of regulators in series.
I recently added the MU receiver ahead of my buffalo I used a standard TP supply but modified for much lower noise and followed with an L C filter.
When I first switched on the sound was a bit rough but over the period of a few days it became much nicer. As all the other elements were "run in" already the only conclusion I could reach was that I was hearing the receiver & it's power supply running in. my conclusion is that digital circuits are indeed sensitive to internal & power supply noise.
Your theory about a single supply is theoretically interesting but I would suggest you don't let you theory get in the way of trying separate supplies. I suspect that your ears may prefer it.
Particularly for analogue & digital elements the earthing will get messed up without separates supplies.
cheers
mike
Which transport for buffalo?
Have folks incorporated the Buffalo into an existing transport? I believe Russ described a mod to feed the SACD stream out of a Denon 1920 into the Buffalo. Anyone else do any modification of that type to some equipment? I want to pick up something and would prefer not to enter totally uncharted territory.
Thanks much!
peter
Have folks incorporated the Buffalo into an existing transport? I believe Russ described a mod to feed the SACD stream out of a Denon 1920 into the Buffalo. Anyone else do any modification of that type to some equipment? I want to pick up something and would prefer not to enter totally uncharted territory.
Thanks much!
peter
Hey Folks,
I am away from home on a hunting trip, so I have not had a chance to reply to a lot things.
Let me just give a brief update.
Placid - well it works very very well, but I am in the midst of redesigning it slightly to make it more robust and DIY friendly. As it is it operates a bit on the hot side under certain use cases. So I am implementing more robust heat sinking capability and it will use all through hole parts. We may still offer the current Placd to folks who want it, but will likely de-rate it to 100-150ma per output.
Counterpoint - again, works very well, but I have learned a lot from the prototype which I am applying to a new version. The first cut while workable is not finished.
MESH - Ah yes MESH, something new. Its actually designed to be a muti-feedback loop fully differential active filter, but I have been using on the output of both Opus and Buffalo with excellent results. It has a highish input impedance(2K as I have it setup), so the DACs are used voltage output. I know the datasheet says Buffalo not supposed to perform as well voltage output, but I don't think they ever tested it with an output stage like this. Basically I am using MESH as a 3 pole low pass at about 60khz. The first pole is prior to the active stage and ensures the active stage is always within it's GBWP, that is it will never be asked to slew faster than it max slew rate. It sounds amazing.
As for feeding Buffalo with placid. I think it does help to feed the linear regulators from a clean supply. It gives them less junk to have to regulate out on the input side. I am feeding VA/VD from a placid.
Cheers!
Russ
I am away from home on a hunting trip, so I have not had a chance to reply to a lot things.
Let me just give a brief update.
Placid - well it works very very well, but I am in the midst of redesigning it slightly to make it more robust and DIY friendly. As it is it operates a bit on the hot side under certain use cases. So I am implementing more robust heat sinking capability and it will use all through hole parts. We may still offer the current Placd to folks who want it, but will likely de-rate it to 100-150ma per output.
Counterpoint - again, works very well, but I have learned a lot from the prototype which I am applying to a new version. The first cut while workable is not finished.
MESH - Ah yes MESH, something new.
Its actually designed to be a muti-feedback loop fully differential active filter, but I have been using on the output of both Opus and Buffalo with excellent results. It has a highish input impedance(2K as I have it setup), so the DACs are used voltage output. I know the datasheet says Buffalo not supposed to perform as well voltage output, but I don't think they ever tested it with an output stage like this. Basically I am using MESH as a 3 pole low pass at about 60khz. The first pole is prior to the active stage and ensures the active stage is always within it's GBWP, that is it will never be asked to slew faster than it max slew rate. It sounds amazing.As for feeding Buffalo with placid. I think it does help to feed the linear regulators from a clean supply. It gives them less junk to have to regulate out on the input side. I am feeding VA/VD from a placid.
Cheers!
Russ
I fitted some "teddyregs" to both the IVY and VA/VD supplies of my buffalo and it does make a differencce. These are kinda superregulated supplies, here is a link to a better explanation. I'm using the LCDPS/LCBPS as supply into them.
What I hear is better resolution/separation and transients are spectacular. Immediacy of vocals is very good. Moves it from a good DIY dac right up the foodchain.
I believe that the regulator shown above has a fairly high ouput impedance and supposedly something with a lower impedance would be even better. Suppose thats what the placid would be!
Fran
What I hear is better resolution/separation and transients are spectacular. Immediacy of vocals is very good. Moves it from a good DIY dac right up the foodchain.
I believe that the regulator shown above has a fairly high ouput impedance and supposedly something with a lower impedance would be even better. Suppose thats what the placid would be!
Fran
Because there are on board regulators, one option is also to just have a purely passive CLC or CLCLC filter.
I would recommend inductors in both legs to block all possible routes for VHF & RF to creep in.
Very easy to build and in this kind of circuit performance that is hard to better.
cheers
mike
I would recommend inductors in both legs to block all possible routes for VHF & RF to creep in.
Very easy to build and in this kind of circuit performance that is hard to better.
cheers
mike
Heres a few pics of the teddyregs in place:
and closer:
The boards are pretty small so its fairly easy to fit them in - although there ain't much room for a standoff.
Fran
An externally hosted image should be here but it was not working when we last tested it.
and closer:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The boards are pretty small so its fairly easy to fit them in - although there ain't much room for a standoff.
Fran
Just finished up mine this weekend, and it sounds great as is, MUX-Buff-IVY. No real problems, although it wasn't clear to me for a bit that the MUX didn't need the selector switch installed for a one-input SPDIF setup.
Thanks very much, Russ and Brian, for making this available to us, and thanks for making the boards robust enough to stand up to my amateurish soldering skills.
Now I just need to find a few 10nf caps for the IVY mod, and then sit back and try to keep from screwing around with it too much more. - Pat
Thanks very much, Russ and Brian, for making this available to us, and thanks for making the boards robust enough to stand up to my amateurish soldering skills.
Now I just need to find a few 10nf caps for the IVY mod, and then sit back and try to keep from screwing around with it too much more. - Pat
Russ and Brian,
In regards to the Denon as a transport. Would it be possible to cut the analog video portion of the main PCB right off without any problems? I have looked at it and they even put a line so I can cut straight. I have gutted the Denon to make a top loader DSD transport and I could use the extra space. I am getting ready for a lot of work in the next weeks. I am waiting for all of the parts for my balanced Aikido boards and my order from TP. I have everything for the HTPC except a power/reset switch. I need some classy simple push button or two position rotary switches for the two OTTO relays.
In regards to the Denon as a transport. Would it be possible to cut the analog video portion of the main PCB right off without any problems? I have looked at it and they even put a line so I can cut straight. I have gutted the Denon to make a top loader DSD transport and I could use the extra space. I am getting ready for a lot of work in the next weeks. I am waiting for all of the parts for my balanced Aikido boards and my order from TP. I have everything for the HTPC except a power/reset switch. I need some classy simple push button or two position rotary switches for the two OTTO relays.
Re: S&B 102 Tx's
I think they sell only to the company that makes up the pre amps these days - that is a great pity for the DIY market. But you could try to email them and see what they say.
But I have to say I think mine sound much better now that they are out of their cans so you may want to look around for some that come like that. rolls gives advice on this in this thread
good luck
mike
tubemooley said:
I think they sell only to the company that makes up the pre amps these days - that is a great pity for the DIY market. But you could try to email them and see what they say.
But I have to say I think mine sound much better now that they are out of their cans so you may want to look around for some that come like that. rolls gives advice on this in this thread
good luck
mike
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