miniDSPs, external DaCs and subwoofers

[SamJames]

Hi there! I was thinking about getting a subwoofer and using a miniDSP to integrate it into my system. 
I was just wondering how best to use it using an external dac. I’m just struggling to see how the signal is handled by the miniDSP. If I use the analog inputs, after a preamp, will it then convert it to digital, before applying EQ and filters, before using its internal DAC? Does this render any external DAC a waste of time?
My concern is that this will ultimately bottleneck the system a bit, or at least undermine another DAC that may perform a bit better. 
Are there alternatives out there that avoid this (if it is the case)? 

[Ittaku]

Yes it will do A to D to A again so it renders any external DAC useless. The alternative is to use one of the D range of devices from miniDSP which do everything in the digital domain and allow you to use an external DAC instead. The DAC in the miniDSP is below average level by today's standards. Just about any standalone DAC will outperfrom it.

[Snoopy8]

Agree with Con that ideally all DSP should be done in the digital domain.

 

If that is not possible , then feed 2 sets of analog signals, one to the mains  and other to  miniDSP to the sub. Yes, the signal to the sub will suffer a A to D and then a D to A and is compromise. But is the compromise smaller than the gain made by integrating the sub properly?  There are people who are happily living with this compromise.

 

The other option is to get a better, more expensive, DSP, e.g. Dspeaker X4, DEQX.  In my instance, my Behringer DCX2496 was upgraded with better input and output stages which made a significant difference. 

 

Please note that you need to invest time and effort to integrate a sub into a stereo setup.  You need to understand and measure the room. Done right, it significantly improves the music experience.

[aechmea]

 

I don't know the features of Mini-DSP, but this is how I configure my system with a DEQX and an external DAC (arguably no improvement and unnecessary overkill).  May help visualizing what you might do.

 

I keep everything in the digital domain for as long as possible to avoid any A - D - A conversions, then DA at the last step.  If you have analogue sources then you will need at least one ADA conversion.  Don't know how transparent they are since I have never done it myself.  Lots of people have DSP in otherwise analogue systems, so it can't be too bad.

 

However the "final" DAC is the one that you hear; another one before that is a moot point.

 

Like Snoopy says you have to put some work into DSP and sub integration but the outcome is worth it.

[cazzesman]

41 minutes ago, Ittaku said:

Yes it will do A to D to A again so it renders any external DAC useless. The alternative is to use one of the D range of devices from miniDSP which do everything in the digital domain and allow you to use an external DAC instead. The DAC in the miniDSP is below average level by today's standards. Just about any standalone DAC will outperfrom it.

@gibbo9000 has the minidsp SHD from memory which has the Dac and Pre plus it should do all you want.  

 

https://www.minidsp.com/products/streaming-hd-series/shd

 

He might shed some light on the DAC quality.  

 

I would drop minidsp an email, tell them what you have and what you want to achieve.   I found their response to questions very prompt.

 

Regards Cazzesman

Edited February 11, 2020 by cazzesman

[Ittaku]

2 hours ago, cazzesman said:

@gibbo9000 has the minidsp SHD from memory which has the Dac and Pre plus it should do all you want.  

 

https://www.minidsp.com/products/streaming-hd-series/shd

 

He might shed some light on the DAC quality.  

 

I would drop minidsp an email, tell them what you have and what you want to achieve.   I found their response to questions very prompt.

 

Regards Cazzesman

The SHD is a good option since it has both analog and digital in and out. You'll still be able to benefit from using a separate DAC for your mains whilst the DAC quality of the subwoofer is not going to be critical (I use the analogue out from a miniDSP OpenDRC DAC for my subwoofer but a far far better DAC for my mains myself.) The HD series have better built in DACs than their usual offerings as well, but they will still fall short of a separate DAC in quality.

Edited February 11, 2020 by Ittaku

[gibbo9000]

1 hour ago, cazzesman said:

@gibbo9000 has the minidsp SHD from memory which has the Dac and Pre plus it should do all you want.

I have the Studio version (all digital) of the SHD - so unfortunately no view on its DAC quality in the straight SHD version. 

The straight SHD version can certainly handle what you want but it will, as @Ittaku says, do A > D > A.  Provides the miniDSP flexibility of I/O mapping with filters and EQ (core to sub integration), along with being a competent pre-amp for handling multiple sources (incl streaming), and bring Dirac Live Room Correction (which I find excellent!). The Studio version I have is extremely good and, in the digital domain, is up there with my ultraRendu.  So if the analogue version follows same suite it won't be too shabby.

What external DAC do you have?

 

Gibbo

 

[H.E. Pennypacker]

Check out the NAD c658.

Edited February 11, 2020 by furtherpale

[SamJames]

22 hours ago, aechmea said:

 

I don't know the features of Mini-DSP, but this is how I configure my system with a DEQX and an external DAC (arguably no improvement and unnecessary overkill).  May help visualizing what you might do.

 

I keep everything in the digital domain for as long as possible to avoid any A - D - A conversions, then DA at the last step.  If you have analogue sources then you will need at least one ADA conversion.  Don't know how transparent they are since I have never done it myself.  Lots of people have DSP in otherwise analogue systems, so it can't be too bad.

 

However the "final" DAC is the one that you hear; another one before that is a moot point.

 

Like Snoopy says you have to put some work into DSP and sub integration but the outcome is worth it.

Thanks! This is a helpful way to think about it. Yeah keeping it all digital for as long as possible seems like a great way to do it 

[SamJames]

21 hours ago, gibbo9000 said:

I have the Studio version (all digital) of the SHD - so unfortunately no view on its DAC quality in the straight SHD version. 

The straight SHD version can certainly handle what you want but it will, as @Ittaku says, do A > D > A.  Provides the miniDSP flexibility of I/O mapping with filters and EQ (core to sub integration), along with being a competent pre-amp for handling multiple sources (incl streaming), and bring Dirac Live Room Correction (which I find excellent!). The Studio version I have is extremely good and, in the digital domain, is up there with my ultraRendu.  So if the analogue version follows same suite it won't be too shabby.

What external DAC do you have?

 

Gibbo

 

 

19 hours ago, furtherpale said:

Check out the NAD c658.

These both sound like great options! Have the features I’ll need for sure. 
I only have a Schiit Modi 3, nothing flash but it sounds like it improves upon the internal Dacs. I’m mostly wanting to think my system through so that I’m not cornered into going down one path because of one piece of gear. 
 

Thanks everyone for your help here! 

[H.E. Pennypacker]

44 minutes ago, SamJames said:

 

These both sound like great options! Have the features I’ll need for sure. 
I only have a Schiit Modi 3, nothing flash but it sounds like it improves upon the internal Dacs. I’m mostly wanting to think my system through so that I’m not cornered into going down one path because of one piece of gear. 
 

Thanks everyone for your help here! 

You can’t use an external DAC with either - unless you want the DAC output reconverted to digital then back to analogue again. The nad uses 32bit Sabre DACs - so I’d be surprised if the schitt came close anyway.

[Ittaku]

1 hour ago, furtherpale said:

You can’t use an external DAC with either - unless you want the DAC output reconverted to digital then back to analogue again. The nad uses 32bit Sabre DACs - so I’d be surprised if the schitt came close anyway.

Just FYI on the "32 bit DACs" comment. I quote "the hot new 32 bit DACs are actually 6 bit DACs with a 32 bit digital filter":

https://www.msbtechnology.com/faq/what-about-32-bit-dacs/

[H.E. Pennypacker]

2 hours ago, Ittaku said:

Just FYI on the "32 bit DACs" comment. I quote "the hot new 32 bit DACs are actually 6 bit DACs with a 32 bit digital filter":

https://www.msbtechnology.com/faq/what-about-32-bit-dacs/

I was referencing the series... I really don’t care how they get to the quality that comes out of them or the nitrate of any dac... but these guys who aren’t competitors have a very nice breakdown of how they work (which I also don’t care a great deal about).:

 

https://www.audioasylum.com/audio/digital/messages/15/153466.html

Edited February 12, 2020 by furtherpale

[Ittaku]

45 minutes ago, furtherpale said:

I was referencing the series... I really don’t care how they get to the quality that comes out of them or the nitrate of any dac... but these guys who aren’t competitors have a very nice breakdown of how they work (which I also don’t care a great deal about).:

 

https://www.audioasylum.com/audio/digital/messages/15/153466.html

Thanks, pretty much confirms it.

[gibbo9000]

7 hours ago, SamJames said:

I’m mostly wanting to think my system through so that I’m not cornered into going down one path because of one piece of gear. 

Getting back to basics, this is a good guiding thought to help through the multiple options.  Some great all in one devices that help solve parts of the problem, and bundle other things that may hinder flexibility later.  If you like experimenting and trying different things perhaps keep it simple and separate - I really enjoyed that for a long time.

Depending on your speakers, and cross over calibration available on the sub you buy, you may not need any form of processing on either main or sub signal, or you could use something like a miniDSP 2x4 as suggested above somewhere to manage sub crossover only.  I had an SVS SB-2000 with my floorstanders without any additional crossover management.

Not sure if you do much streaming, or just have your own collection, or CD's etc. to feed DAC.  If you don't want to be locked in I would try to keep the DAC separate and the main system downstream all analogue.  There is a great trade in DACs of all sorts here.  I started with a Schitt Modi and eventually settled on a Mytek Brooklyn before going all active. 

Also many ways to keep streaming separate if you use it, especially if you are slightly tech inclined. 

[SamJames]

1 hour ago, gibbo9000 said:

Getting back to basics, this is a good guiding thought to help through the multiple options.  Some great all in one devices that help solve parts of the problem, and bundle other things that may hinder flexibility later.  If you like experimenting and trying different things perhaps keep it simple and separate - I really enjoyed that for a long time.

Depending on your speakers, and cross over calibration available on the sub you buy, you may not need any form of processing on either main or sub signal, or you could use something like a miniDSP 2x4 as suggested above somewhere to manage sub crossover only.  I had an SVS SB-2000 with my floorstanders without any additional crossover management.

Not sure if you do much streaming, or just have your own collection, or CD's etc. to feed DAC.  If you don't want to be locked in I would try to keep the DAC separate and the main system downstream all analogue.

Yeah I think keeping it seperate like this sounds like a fun way to try different things and slowly workout what works. 
 

Also, how did you find the SVS sub? I was looking at that one as a possible option? 

[gibbo9000]

7 minutes ago, SamJames said:

Also, how did you find the SVS sub?

Very happy with it.  Used it in combo with Q-Acoustics Concept 500's and using its crossover and phase adjustments it fitted in well without any additional crossover management.  I used REW and Umik mic to help set it up.  Just used low level pre-out to drive it.  Went for the SB-2000 - so larger driver for lower frequency, and the sealed version which I sense is better for 2.1 use (ported more for home theatre).

[SamJames]

I’m glad you had such a good experience with it. It sounds like they’re a great sub!