Minisdsp Questions

[terfenol-D]

I am replacing my NAD C658. I was going to replace it with an Anthem STR but passed on that. Instead I am going with a preamp with no room correction and would like to add a minidsp product for integration of sub and speakers. My questions are:

• MiniDSP 2x4HD vs MiniDSP Flex. If I would like to use Dirac I pretty much have to go with the MiniDSP flex correct?
• RCA vs Balanced. I'm not really sure which way to go here. My pre has both balanced and RCA outputs. My sub only has an RCA input. My preamp outputs 16v balanced. Will that fry the Minidsp Flex which indicates it has a maximum of 4v input? Similar question on going from minidsp balanced output to RCA input on my sub?
• Can the MiniDSP flex be used in only room correction mode? IE - turn off the volume control so that volume can be controlled by the preamp I am going with? If not, would I just set the miniDSP to max volume and then hide the remote?

Thanks for any advice you offer.

 

[staticV3]

MiniDSP 2x4HD vs MiniDSP Flex. If I would like to use Dirac I pretty much have to go with the MiniDSP flex correct?

No. The miniDSP DDRC-24 is a 2x4 HD with Dirac.

RCA vs Balanced. I'm not really sure which way to go here.

You can easily connect RCA out to balanced inputs.
With the right cable, the connection is even fully balanced just like native XLR out.

You cannot as easily connect balanced out to RCA in.
In many cases, performance will drop.

My preamp outputs 16v balanced. Will that fry the Minidsp Flex which indicates it has a maximum of 4v input?

I think so.

Lastly, do you listen to analog sources like vinyl or tape?

Because if all your sources are digital (CD, TV, Streaming, etc) then you'd be better off sending those digitally straight to the miniDSP and letting it convert them to analog.

 

[terfenol-D]

No. The miniDSP DDRC-24 is a 2x4 HD with Dirac.


You can easily connect RCA out to balanced inputs.
With the right cable, the connection is even fully balanced just like native XLR out.

You cannot as easily connect balanced out to RCA in.
In many cases, performance will drop.

It would be balanced out to RCA in on the subwoofer. It looks like I should stick with the RCA version then. In either case - if I can use the DDRC-24 it would be RCA connections so I guess problem solved.

I think so.

Lastly, do you listen to analog sources like vinyl or tape?

Because if all your sources are digital (CD, TV, Streaming, etc) then you'd be better off sending those digitally straight to the miniDSP and letting it convert them to analog.

I thought of that but I do have a Vinyl collection. I thought about getting a puffin for digital out but part of the consideration on selecting the pre-amp was esthetic…my wife likes the blue meters!

Thank you for the response.

 

[Shinrei]

You can easily connect RCA out to balanced inputs.
With the right cable, the connection is even fully balanced just like native XLR out.

Wow! Can you elaborate on how the RCA to XLR cable works and what cable might do that?

Cheers

 

[staticV3]

Wow! Can you elaborate on how the RCA to XLR cable works and what cable might do that?

A balanced audio connection rejects noise and hum using a differential input and impedance balance, which ensures that common-mode noise is induced equally into all wires.

Most RCA outputs have significant output impedance on their Signal pin, but close to none on the Ground pin -> Imbalance.

To restore balance, you can insert an appropriate resistor between the Ground pin and cable:


In case the DAC has some inductance or capacitance on the Signal out, then those should be matched as well.

 

[MAB]

It would be balanced out to RCA in on the subwoofer. It looks like I should stick with the RCA version then. In either case - if I can use the DDRC-24 it would be RCA connections so I guess problem solved.




I thought of that but I do have a Vinyl collection. I thought about getting a puffin for digital out but part of the consideration on selecting the pre-amp was esthetic…my wife likes the blue meters!

Thank you for the response.

I've used many MiniDSP with analog inputs as preamp, most recently SHD, Flex, and Flex HTx. They work great any analog source I have including phono preamps. I even used biquad filters to do RIAA EQ in digital domain on my SHD, just for fun. I confidently use these MiniDSP models as preamps, I have diminishing need for the many analog preamps I own.

Regarding balanced vs. RCA, the Flex HTx has both balanced and RCA analog output, solves most any connectivity problem you have.

One moment, please...

I use one of these for a DIY JBL M2 system plus subwoofers. I use it as the crossover, and preamp for my digital and analog sources, with a turntable connected.

 

[MAB]

• Can the MiniDSP flex be used in only room correction mode? IE - turn off the volume control so that volume can be controlled by the preamp I am going with? If not, would I just set the miniDSP to max volume and then hide the remote?

Yes, it can be used as a fixed-gain crossover plus DSP box, with gain structure set to match your preamp.

 

[Salt]

A balanced audio connection rejects noise and hum using a differential input and impedance balance, which ensures that common-mode noise is induced equally into all wires.

Most RCA outputs have significant output impedance on their Signal pin, but close to none on the Ground pin -> Imbalance.

To restore balance, you can insert an appropriate resistor between the Ground pin and cable:
View attachment 372319

In case the DAC has some inductance or capacitance on the Signal out, then those should be matched as well.

Compensation of R on signal pin by adding R to Ground would result in drain to shield if not R-ed too, not?

 

[MAB]

RCA vs Balanced. I'm not really sure which way to go here. My pre has both balanced and RCA outputs. My sub only has an RCA input. My preamp outputs 16v balanced. Will that fry the Minidsp Flex which indicates it has a maximum of 4v input? Similar question on going from minidsp balanced output to RCA input on my sub?

Regarding your sub, MiniDSP provides guidance on balanced out to RCA in, so you don't need to rely on ASR and the usual online specualtion:

Flex Balanced connectivity: Which TRS to RCA cable should I use?

The Flex balanced is balanced in/out. If you'd like to use an unbalanced amplifier (e.g. Powered subwoofer) downstream of the Flex series, here is the recommended TRS to RCA cable to minimize detrimental effect on the audio quality. Note how...

support.minidsp.com

They give the exact wiring, and specific use and do-not-use conditions. And sell the cables for reasonable price:

 

[AaronJ]

the minidsp flex will clip at 4V input, not fry. It’s possible to clip with a hot phono cartridge depending on how much gain you’re running. 16V out from the preamp is just a maximum output, not a nominal value. If you’re using an analog source I recommend setting volume upstream because the Flex input will clip regardless of its own output volume.

I have my MiniDSP flex set to max volume and use the preamp for volume control. I just want to to be set and forgotten.