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Other Stuff => Archived Manufacturer Circles => Mivera Audio => Topic started by: mresseguie on 14 Dec 2017, 03:35 pm

Title: Mivera DAC/Preamp Thread
Post by: mresseguie on 14 Dec 2017, 03:35 pm
Beware of vicious dog.  :nono:

Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 15 Dec 2017, 07:25 am
Thanks Michael!

 Well I'm working on 2 units. The first version I think might be a bit expensive for a group buy. The 2nd, my goal is to at least match the 1st version in sound quality, in a stripped down version with digital inputs only. But we are talking spring/summer before release.
Title: Re: Mivera DAC/Preamp Thread
Post by: Nick77 on 15 Dec 2017, 01:15 pm
So this will be a DAC with volume pot to eliminate the need for a preamp? What price brackets??   :scratch:
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 15 Dec 2017, 05:33 pm
My reference DAC/Pre uses a fully balanced Slagleformer Analog volume control. My goal with this next gen DAC/pre will be to exceed the sound quality of the Slagleformer’s, with a 64 bit floating point “DSD wide” digital volume control. Price in lots of 20 will be $5000 each.
Title: Re: Mivera DAC/Preamp Thread
Post by: gregfisk on 15 Dec 2017, 08:11 pm
My reference DAC/Pre uses a fully balanced Slagleformer Analog volume control. My goal with this next gen DAC/pre will be to exceed the sound quality of the Slagleformer’s, with a 64 bit floating point “DSD wide” digital volume control. Price in lots of 20 will be $5000 each.

I have heard the Don Sach pre that mresseguie has. It boasts the 48-step Khozmo volume pot and is extremely transparent. Not sure how this would fit into what your plans are but something to consider. Another nice feature is that is also has the ability to act as a balance control which I have always liked. Since you seem open to other ideas I thought I would throw this one out. 
Title: Re: Mivera DAC/Preamp Thread
Post by: sfox7076 on 15 Dec 2017, 10:02 pm
I prefer iron to resistors in a preamp.  But that is just me.  I run a balanced slagleformer preamp with an 01A “sound processor” concept using the gyrator championed by Ale Of Bartola Valves.  Sonic bliss. 
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 15 Dec 2017, 10:26 pm
I haven’t heard any resistive analog volume controls that could come anywhere close to the Slagleformer’s. The only way I will replace Slagleformer’s in my dac/pre is if I can exceed their performance. Keep in mind my Weiss OP2-BP based active stage has an ultra low 10 ohm output impedance, as well can sink/source 60mA of current in pure class A operation, while meeting the spec-sheet rated specs.

http://www.weiss.ch/files/downloads/op1-bp/OP1-BP-Datasheet-R1.pdf

Very few people who ever tried Slagleformer’s, have ever used a gainstage this robust to drive them.  Once we get 10 dB down from unity output of the Slagleformer’s, combined with my active stage, output impedance is at 0 ohms. Very few people will ever turn up higher. You’ll be able to drive efficient speakers easily from the XLR outputs of this DAC/pre.
Title: Re: Mivera DAC/Preamp Thread
Post by: david45 on 16 Dec 2017, 03:01 pm
Mike,

Congrats on having your own circle!

I'm guessing you are going to offer an updated streamer/server at some point as well? So that would be a complete 3-chassis solution when combined with your dac/pre and amplifier?

Also is everything going to be upsampled to dsd256 or dsd512 this time around? Personally as long as it sounds good I don't really care and it could probably be updated with a different module in the future anyways (?). If your dac is better or as good as the T+A Dac 8 dsd I'll be happy and in any case it is going to be night and day when compared to my current oppo 105 and its tidal app or the modded SBT I still own!!  :thumb:

Keep up the excellent work and have a great weekend!
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 16 Dec 2017, 03:27 pm
Mike,

Congrats on having your own circle!

I'm guessing you are going to offer an updated streamer/server at some point as well? So that would be a complete 3-chassis solution when combined with your dac/pre and amplifier?

Also is everything going to be upsampled to dsd256 or dsd512 this time around? Personally as long as it sounds good I don't really care and it could probably be updated with a different module in the future anyways (?). If your dac is better or as good as the T+A Dac 8 dsd I'll be happy and in any case it is going to be night and day when compared to my current oppo 105 and its tidal app or the modded SBT I still own!!  :thumb:

Keep up the excellent work and have a great weekend!

Thanks!

Actually there won’t be any need for a standalone streamer anymore. Because it will have a built in Ravenna Audio over IP input. No more USB. Just like my Purestream DAC it will run at 11.289Mhz DSD only. By running at 11.289Mhz only, this allows us to use lower jitter clocks than are possible to use if you want to support DSD 512, and at the same time achieve lower out of band noise than any DSD 512 capable DAC like the T+A DAC 8 DSD. Because that DAC also needs to support all of the other DSD rates, they must set their analog filter at a lower frequency. This results in higher out of band noise at 512, than my DAC has at 256. With the benefit of much lower jitter clocks.

Here’s the clock that will be the base clock option for the Puremusic:

http://www.pulsarclock.com/ds/Pulsar_Clock.pdf

The 22.579Mhz version. However since the unit will have DIL14 clock sockets, I’ll be able to offer even higher end clock options as well. Our reference when designing this unit will be the MSB Select DAC 2. If my client who owns one doesnt think it’s just as good or better with his Focal Utopia headphones connected direct to the analog outputs, the Puremusic will never be released as a group buy unit for $5000.



Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 16 Dec 2017, 03:50 pm
For those who haven’t read this, here’s a review of my previous gen Purestream USB DAC compared directly with the MSB Select 2.

https://www.head-fi.org/threads/possible-end-game-dynamic-headphone-rig-focal-utopia-mivera-superstack.838570/

First thing I thought when I read that review is I have a lot of work to do :)
Title: Re: Mivera DAC/Preamp Thread
Post by: david45 on 16 Dec 2017, 03:51 pm
Thanks!

Actually there won’t be any need for a standalone streamer anymore. Because it will have a built in Ravenna Audio over IP input. No more USB. Just like my Purestream DAC it will run at 11.289Mhz DSD only. By running at 11.289Mhz only, this allows us to use lower jitter clocks than are possible to use if you want to support DSD 512, and at the same time achieve lower out of band noise than any DSD 512 capable DAC like the T+A DAC 8 DSD. Because that DAC also needs to support all of the other DSD rates, they must set their analog filter at a lower frequency. This results in higher out of band noise at 512, than my DAC has at 256. With the benefit of much lower jitter clocks.
And consequently the server you used to offer is still up to the task and the NUC is perfectly up to date I assume? It's still going to be compatibe with Daphile, Roon+HQ Player and offer the same airplay emulator?

Our reference when designing this unit will be the MSB Select DAC 2. If my client who owns one doesnt think it’s just as good or better with his Focal Utopia headphones connected direct to the analog outputs, the Puremusic will never be released as a group buy unit for $5000.


Now that's what I call reassuring! Go hard or go home!!   :thumb:
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 16 Dec 2017, 03:59 pm
And consequently the server you used to offer is still up to the task and the NUC is perfectly up to date I assume? It's still going to be compatibe with Daphile, Roon+HQ Player and offer the same airplay emulator?
 

Now that's what I call reassuring! Go hard or go home!!   :thumb:

What I’m recommending now is to just use Roon ROCK on a little NUC. Roon now has their upsampling dialed in to sound much better than HQplayer, while using 1/4 the CPU power. As an alternative, Daphile’s also excellent, and is completely free. It’s Daphile’s latest upsampling algorithms that I had the Roon engineers use as a reference point when developing their latest algorithms. However still more CPU demanding than Roon. So still need a powerful I7 quad core processor. Roon’s Upsampling is so efficient I can even do it easily on my 3 year old I3 NUC.
Title: Re: Mivera DAC/Preamp Thread
Post by: david45 on 16 Dec 2017, 04:12 pm
Ok so you're not planning on updating the superserve for now. What about the airplay emulator? Is it going to be integrated to your Dac somehow?
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 16 Dec 2017, 04:24 pm
Ok so you're not planning on updating the superserve for now. What about the airplay emulator? Is it going to be integrated to your Dac somehow?

All my Superserve was, was an Intel skull canyon NUC, or a Asrock Deskmini 110. You can install Roon Rock or Daphile on either one of them. All of my clients who bought them are now running Roon ROCK on them.

Airplay is something that’s no longer required. I’m going to have a Ravenna fiber optic Audio over IP input on the Puremusic. As long as you have the free virtual soundcard software running on your Mac, Windows, or Linux based PC, that’s all you need. The Puremusic will populate on the list of audio devices just the same as a built in sound card, or USB DAC. As long as it’s connected to the same network. I’ll be including a very nice fibre optic switch with every unit as well. Along with a quality fiber cable that’s resistant to bending.

https://youtu.be/1bHVguGn4hU
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 16 Dec 2017, 04:40 pm
We’re actually working on a very advanced DSP system right now that will do upsampling, room correction, crossovers etc. It will run completely in the background on any Windows, Mac or Linux PC. To access the control panel you can do it remotely via mobile device, and change the settings on the fly while listening to music. The beauty of this system is all sound from the computer can be passed through it. No matter which application. Foobar, Jriver, YouTube, Roon, you name it. If it’s Audio that can be played on your computer, it can be passed through this engine, then directly out via Ethernet to the Puremusic.
Title: Re: Mivera DAC/Preamp Thread
Post by: Tomy2Tone on 16 Dec 2017, 05:53 pm
Roon now has their upsampling dialed in to sound much better than HQplayer, while using 1/4 the CPU power.

Hadn't heard this before. That's good to know.
Title: Re: Mivera DAC/Preamp Thread
Post by: Audiogeek2 on 17 Dec 2017, 05:29 am
Mike, i hate hqp - its awkward and unnecessarily fiddly. Remember; I had to get you to set it up!

Having said that, It leaves Roon far behind sound quality wise, particularly when using convolution.
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 17 Dec 2017, 05:48 am
Mike, i hate hqp - its awkward and unnecessarily fiddly. Remember; I had to get you to set it up!

Having said that, It leaves Roon far behind sound quality wise, particularly when using convolution.

Have you tried Roon since they made all the improvements? I know you didn’t like it back when I also felt the same. But the recent improvements changed that for me and everyone else. You’re the only one of my clients left who is still using HQP. I did some extensive comparisons recently and felt HQP was over-smooth, and just not natural compared to Roon. Even the new XTR filters.
Title: Re: Mivera DAC/Preamp Thread
Post by: firedog on 17 Dec 2017, 07:30 am
I still think the HQP filters are very slightly better, but not enough to justify messing with HQP.  Doing it all thru the Roon DSP works great.
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 17 Dec 2017, 08:04 am
Are you using a pure DSD only DAC? Yes when using DAC’s that go through dual stages of SRC/SDM such as when you upsample with any DAC with a Sabre chip, this may be the case. I liked it with my old Resonessence Mirus with Sabre chip. But when used with ultra high resolution pure DSD DAC’s, that’s when the over-processed, over-smoothed sound becomes very apparent. Since 90%+ HQP users don’t have pure DSD DAC’s, I can see why it’s popular among this crowd. Sure the T+A DAC 8 DSD guys liked it, but that was way back before Roon optimized their upsampling algorithms. But one thing it has over Roon and Daphile is the “DSD wide” volume control.
Title: Re: Mivera DAC/Preamp Thread
Post by: Audiogeek2 on 19 Dec 2017, 03:39 am
Mike, for me its the convolution  engine where Roon comes second. Filters and modulator combination is more a personal choice.
Title: Re: Mivera DAC/Preamp Thread
Post by: brj on 19 Dec 2017, 07:17 am
I have Roon and HPQ, but unless I missed it somewhere, HQP is still the only software product that can apply a convolution filter to DSD natively.

I'm going from memory, though, and I haven't had had time to be as diligent in reading release notes lately...

(Mike, your DSP solution sounds interesting, as I have two different routes through the Mac Mini that I use as a music server - one for 2-channel audio using Roon/HQP and that uses Loopback for those times when I want to route AV material through my big rig.  Perhaps it's worth discussing that in a separate thread?)
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 19 Dec 2017, 08:02 am
Mike, for me its the convolution  engine where Roon comes second. Filters and modulator combination is more a personal choice.

But did you try it since they made major upgrades to the convolution engine? Last time we discussed this via email you said you haven’t tried it since 1.3 initially came out. There’s been probably a dozen upgrades to the upsampling and convolution engine since then. If you tried the latest version and still find it subpar for your tastes then I can respect that. But if all of this opinion is based on when it was pretty much broken at first launch then it doesn’t reflect a valid opinion today.
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 19 Dec 2017, 08:04 am
I have Roon and HPQ, but unless I missed it somewhere, HQP is still the only software product that can apply a convolution filter to DSD natively.

I'm going from memory, though, and I haven't had had time to be as diligent in reading release notes lately...

(Mike, your DSP solution sounds interesting, as I have two different routes through the Mac Mini that I use as a music server - one for 2-channel audio using Roon/HQP and that uses Loopback for those times when I want to route AV material through my big rig.  Perhaps it's worth discussing that in a separate thread?)

No Roon can apply DSP to native DSD now just like HQP. This was one of the many updates they made that resulted in a massive quality increase to the convolution. I have more than 1 client using Roon convolution with native DSD and my Purestream DSD 256 only DAC.

This thread is fine for DSP discussion, as DSP is part of how my system works.
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 19 Dec 2017, 08:16 am
I actually figured out how to do a makeshift 64 bit “DSD wide” volume control in Roon to eliminate a Preamp with a pure DSD DAC. It’s kind of a clunky solution but it works.

1- Enable the headroom management and set the dB to whatever you want your maximum level to play at.
2- Enable the PEQ, and use the overall gain slider to adjust volume.
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 19 Dec 2017, 08:50 am
Roon 1.4 was released today! I’ll have to give it a try tomorrow.

https://community.roonlabs.com/t/roon-1-4-is-live-christmas-tree/35225
Title: Re: Mivera DAC/Preamp Thread
Post by: mikeeastman on 19 Dec 2017, 03:04 pm
I've been using Roon 1.3 and in my system it has better SQ than HQPlayer had. If the 1.4 Roon is better  I can't wait to hear it.
Title: Re: Mivera DAC/Preamp Thread
Post by: mikeeastman on 19 Dec 2017, 06:10 pm
I just updated Roon to 1.4  :thumb: :thumb:  I'll have to do some more listing, but so far WOW! Everything has so much more presence and impact, it's like everything got thicker somehow at the same time it's very musical. This had to be the easies update ever and that's from a complete computer idiot.
Title: Re: Mivera DAC/Preamp Thread
Post by: Audiogeek2 on 19 Dec 2017, 07:29 pm
Ok, I will give it another go with Roon convolution in the new year. It would actually be a relief to ditch hqp. Your advice in the past has always been spot on.

On another note, why does the new server/dac require raveena?
The superstream server allready had fibre input. I thought raveena was to replace the usb connection between the superstream and purestream dac. If its an all in one unit, is that still necessary?
Maybe I have not kept up with the technology
Title: Re: Mivera DAC/Preamp Thread
Post by: bavmike on 19 Dec 2017, 07:44 pm
Ok, I will give it another go with Roon convolution in the new year. It would actually be a relief to ditch hqp. Your advice in the past has always been spot on.

On another note, why does the new server/dac require raveena?
The superstream server allready had fibre input. I thought raveena was to replace the usb connection between the superstream and purestream dac. If its an all in one unit, is that still necessary?
Maybe I have not kept up with the technology

Ravenna is a major upgrade in not only sound quality but functionality. No longer do I need to run another computer as a streamer with an OS and software like Roon RAAT or NAA. Ravenna turns the Ethernet into the same thing like USB audio. Plug the DAC into the switch, and it’s available as a sound device for all applications available on the server. Not just Roon or HQP. But more importantly is I’m able to do the clocking and all the digital end much better than is possible with USB.