MiniDSP with a separate DAC and Preamp

[anotherhobby]

Hi everyone,

i'm trying to achieve the same thing as the OP (high pass my speakers and use them together with a sub, anyway i don't want to get rid of my r2r dac)

and i was reading everything here, anyway i;m not sure why there is the need for a secondary dac in this chain "miniDSP > DAC > Poweramps > L+R speakers and miniDSP > DAC > Subwoofer."?

minisdp can't do 2 outputs? one analog with a high pass filter and another one digital with either the full frequencies or even low pass?


thanks

The Flex digital (the version being discussed here) only has digital outputs. No analog out.

 

[oslius]

The Flex digital (the version being discussed here) only has digital outputs. No analog out.

makes sense

are there any better ways to design the signal chain ? other minidsp products with both digital and analog outputs or alternatives to it ?

 

[Probelou]

minisdp can't do 2 outputs? one analog with a high pass filter and another one digital with either the full frequencies or even low pass?

My miniDSP Flex has 4 outputs. They're all digital though which is why I would need a second DAC for my subwoofer.

Output 1 is going to my Chord DAC > Poweramps > L+R speakers and Output 3 is going to a BlueSound Node 2i > Subwoofer. Volume would be controlled digitally with the miniDSP Flex.

Using the setup I've just mentioned means I can no longer use my M-Scaler as the miniDSP only has a maximum delay of 30ms and this is nowhere near what's needed for the M-Scaler. The Hugo TT2 also introduces a 16ms delay when receiving a 96kHz signal (miniDSP list the Flex as 96kHz or 48kHz with Dirac) but this is within addressable limits.

I did discover a weird quirk with the BlueSound Node 2i when it's running as a DAC with fixed output. I have to keep the A/V Mode engaged otherwise everything was out of sync and just sounded odd.

 

[alaios]

Digital Source -> miniDSP -> DAC -> preamp -> amp

In my case a miniDSP OpenDRC-DI

that means for my case (I am writing it down so someone can check my sanity)

1. CD transport->mini dsp -> integrated input of CD
2. streamer ->minidsp ->integrated input of streamer
3. turntable ->???? (minidsp)--->??

 

[catastrofe]

I would have thought that for the OP's original use case the chain would have been:

Music source > DAC > MiniDSP (4 analog out, not digital as he ordered) > Subwoofer & Preamp inputs > Power Amp > Speakers

This would provide HP and LP settings via MiniDSP, along with Dirac if desired.

Placing the MiniDSP prior to the DAC seems counterintuitive to me. Can someone clarify?

 

[anotherhobby]

I would have thought that for the OP's original use case the chain would have been:

Music source > DAC > MiniDSP (4 analog out, not digital as he ordered) > Subwoofer & Preamp inputs > Power Amp > Speakers

This would provide HP and LP settings via MiniDSP, along with Dirac if desired.

Placing the MiniDSP prior to the DAC seems counterintuitive to me. Can someone clarify?

The OP is referring to the digital Flex, which has no DAC, and all of it's outputs digital. In that case, you must have a DAC after it in the chain. I use the regular Flex with no other DAC at all (since it is a DAC), which I think is the more common implementation.

 

[catastrofe]

The OP is referring to the digital Flex, which has no DAC, and all of it's outputs digital. In that case, you must have a DAC after it in the chain. I use the regular Flex with no other DAC at all (since it is a DAC), which I think is the more common implementation.

Understood, but he only purchased the digital version after the connection order was recommended here.

If the recommended connection order had been as I'm thinking, he could have purchased the non-digital Flex. It seems he would have then been able to place the Flex after the DAC for crossover/DSP functionality. Does that make sense? I'm thinking of this connection order for my own system and want to make sure I understand how things fit together.

 

[gwing]

Understood, but he only purchased the digital version after the connection order was recommended here.

If the recommended connection order had been as I'm thinking, he could have purchased the non-digital Flex. It seems he would have then been able to place the Flex after the DAC for crossover/DSP functionality. Does that make sense? I'm thinking of this connection order for my own system and want to make sure I understand how things fit together.

The 'issue' with that path is that you are taking a digital signal, converting it to analog then giving it to the Flex where it will be converted back to digital, processed, then converted back to analog for the second time. That seems inelegant in the extreme to me, whether the double conversion is audible though is a different question.

 

[catastrofe]

The 'issue' with that path is that you are taking a digital signal, converting it to analog then giving it to the Flex where it will be converted back to digital, processed, then converted back to analog for the second time. That seems inelegant in the extreme to me, whether the double conversion is audible though is a different question.

It's definitely inelegant, but if you go MiniDSP > DAC, don't you lose the crossover (and possibly Dirac) function of the Flex? I could be totally confused, but it doesn't seem "right" that you would feed a DSP processed signal to a DAC...‍

 

[gwing]

It's definitely inelegant, but if you go MiniDSP > DAC, don't you lose the crossover (and possibly Dirac) function of the Flex? I could be totally confused, but it doesn't seem "right" that you would feed a DSP processed signal to a DAC...‍

No, its very right to do it that way. The downside though is that you will need as many DAC channels as you output from the MiniDSP. Ok if you output just stereo but if you output say processed main channels as well as two sub channels that will be four channels i.e. a pair of stereo DACs or a multichannel DAC. If you are using the miniDSP as a crossover as well as for equalisation that would then be 2 channels for the highs, 2 channels for the lows and possibly also 2 for the subs, that's six channels you will need DACs for.

 

[catastrofe]

No, its very right to do it that way. The downside though is that you will need as many DAC channels as you output from the MiniDSP. Ok if you output just stereo but if you output say processed main channels as well as two sub channels that will be four channels i.e. a pair of stereo DACs or a multichannel DAC.

Thanks for the clarification, but is there any benefit of a separate DAC (or two) in the chain? The Flex has already processed the signal and will output a 48K stream (if Dirac is used, 96K otherwise) to the downstream DAC. You'd have to either live with the Flex's output sample rate, or up-sample in the DAC.

Seems just as inelegant as passing the stream from a DAC > MiniDSP.

 

[WillBrink]

What comes before the DAC?

As Ray mentioned, you can use a miniDSP before the DAC or in your case, the M-Scaler. I think that is how it works with that Chord gear right? Personally I use a miniDSP SHD as my DAC/DSP/Preamp.

Did that unit just get tested here recently or am I thinking of another? I'd like to go active speakers + that unit + streamer some day.