Minidsp Flex Review (Audio DSP)

[SoySalsaPicante]

I asked the developers if the screen could show named inputs & the reply said no. You'd think that in 2026 it could be programmed

Maybe if they made a new device, but this one was released in 2022.

 

[Endibol]

yes, it's in that way ... the display and (obviously) the remote always shows 1..4

This is true unfortunately and annoying. I hope they will change this soon.

 

[ByteCurious]

I just picked up the miniDSP Flex with Dirac specifically for my stereo listening (2.1) setup. I do have a Marantz SR5015 AVR running Acoustica. However, how can i leverage the miniDSP Flex for the subwoofer (SB-3000)? or dont even bother with it?

 

[voodooless]

I just picked up the miniDSP Flex with Dirac specifically for my stereo listening (2.1) setup. I do have a Marantz SR5015 AVR running Acoustica. However, how can i leverage the miniDSP Flex for the subwoofer (SB-3000)? or dont even bother with it?

Flex only for the sub? Why? The SB-3000 already has a build-in DSP.

 

[ByteCurious]

Flex only for the sub? Why? The SB-3000 already has a build-in DSP.

I also have the WiiM Ultra and applied PEQ that I created from REW and it worked out very well. The only issue I have is I have two listening positions and only one of them had proper timing/sync between the sub and speakers.

My other plan is to actually get rid of the SB3000 for the KEF KC92 since I like its smaller form factor, albeit sacrifice SPL.

Overall I had great results with the WiiM Ultra PEQ. But wanted to explore the miniDSP options and Dirac to see what it’s capable of or whether it actually makes any meaningful improvements.

 

[staticV3]

I just picked up the miniDSP Flex with Dirac specifically for my stereo listening (2.1) setup. I do have a Marantz SR5015 AVR running Acoustica. However, how can i leverage the miniDSP Flex for the subwoofer (SB-3000)? or dont even bother with it?

Typically, you'd disable any DSP on the Marantz and use it as though it was a pure Power Amp.

Then do Flex->Marantz->Mains and Flex->Sub.

 

[Sparkles]

I just picked up the miniDSP Flex with Dirac specifically for my stereo listening (2.1) setup. I do have a Marantz SR5015 AVR running Acoustica. However, how can i leverage the miniDSP Flex for the subwoofer (SB-3000)? or dont even bother with it?

Flex will still pre and post measure and DSP the sub around the "fixed" sound profile of the mains.

You would of course be able to blend and bend the mains as well if you replaced either of the source or power amp duties of the AVR to get a source->Flex->power + sub ->mains chain.

If the AVR has pre amp out and power amp in you could insert the Flex between.

 

[rvsixer]

I just picked up the miniDSP Flex with Dirac specifically for my stereo listening (2.1) setup. I do have a Marantz SR5015 AVR running Acoustica. However, how can i leverage the miniDSP Flex for the subwoofer (SB-3000)? or dont even bother with it?

Not entirely clear to me. So you have a 2.1 setup, AND have a Marantz running Acoustica? Both systems sharing the same sub?

If so, yes the Flex will be your 2.1 system, and the Marantz for multichannel (and amps/speakers/sub must be switched between the two systems aka HT bypass).

If you do not have separate systems and all listening 2ch and multichannel is through the Marantz, the Flex will do no good. You want to disable ALL sub DSP; Marantz/Acoustica expect no sub DSP at all and do ALL necessary integration/DSP of each speaker/sub in the system (exceptions apply to those well versed in multisub integration, and then presenting that sub array to Acoustica...but I don't bother with that any longer as Acoustica does a good job of it and it is MUCH simpler and easier).

If you feel your bass is not performant, it is with certainty a physical/room setup issue (i.e no broadband treatment, sub not in optimal location to support the one single best MLP position it can (for great bass for both single & multiple listening positions, you really need more than a single sub read up on Toole, Welti, etc.)).

I was personally able to ditch the separate 2.x system after broadband room treatment and Acoustica, best 2.x I have ever had as well multichannel all in one system (measured and subjectively).

 

[ByteCurious]

Not entirely clear to me. So you have a 2.1 setup, AND have a Marantz running Acoustica? Both systems sharing the same sub?

If so, yes the Flex will be your 2.1 system, and the Marantz for multichannel (and amps/speakers/sub must be switched between the two systems aka HT bypass).

If you do not have separate systems and all listening 2ch and multichannel is through the Marantz, the Flex will do no good. You want to disable ALL sub DSP; Marantz/Acoustica expect no sub DSP at all and do ALL necessary integration/DSP of each speaker/sub in the system (exceptions apply to those well versed in multisub integration, and then presenting that sub array to Acoustica...but I don't bother with that any longer as Acoustica does a good job of it and it is MUCH simpler and easier).

If you feel your bass is not performant, it is with certainty a physical/room setup issue (i.e no broadband treatment, sub not in optimal location to support the one single best MLP position it can (for great bass for both single & multiple listening positions, you really need more than a single sub read up on Toole, Welti, etc.)).

I was personally able to ditch the separate 2.x system after broadband room treatment and Acoustica, best 2.x I have ever had as well multichannel all in one system (measured and subjectively).

1.) I have a 5.1 Setup with the Marantz SR-5015. Left & Right speakers are pre-out to an external amp (integrated stereo amp but that doesn’t really matter). Integrated amp input = RCA
2.) Listening Position #1 is on my desk/office. Uses the same integrated amplifier as #1 (the external amp, not the SR5015). This is outputting to Speaker A in the integrated amp. Source = XLR input from the miniDSP Flex
3.) Listening Position #2 is using the same Left & Right speakers used in #1 above. This is Speaker B in the integrated amp. Source = XLR input from the miniDSP flex

 

[SanojS]

This is nice and all, but I don't want such a complicated signal path. I am running a 2.1 system with bookshelf speakers and a subwoofer.
I want to build the system using bass mgmt (and DSP if possible) - this is a must for me.
I want to reuse some of my existing gear.

I have two options within my budget constraints:
Throw away all my gear and get a Luxsin X9 as a new centerpiece in my system (don't want to) or (streamer -> DAC -> analog preamp -> minDSP Flex -> subwoofer/power amp).

I don't like either of those options.

I was thinking to use the miniDSP as DAC and DSP, and feed to a preamp for 4-channel volume control (basically the same as the Luxsin does in one box but cheaper and I think the miniDSP has better functions).
I can't find a good multi-channel preamp or volume control... :-(

So, my only viable option would be the Luxsin X9.

If you don't want to run the volume control of the miniDSP, and you don't want to add it after the analog preamp, then this piece of kit is quite useless... am I missing something?

 

[ByteCurious]

This is nice and all, but I don't want such a complicated signal path. I am running a 2.1 system with bookshelf speakers and a subwoofer.
I want to build the system using bass mgmt (and DSP if possible) - this is a must for me.
I want to reuse some of my existing gear.

I have two options within my budget constraints:
Throw away all my gear and get a Luxsin X9 as a new centerpiece in my system (don't want to) or (streamer -> DAC -> analog preamp -> minDSP Flex -> subwoofer/power amp).

I don't like either of those options.

I was thinking to use the miniDSP as DAC and DSP, and feed to a preamp for 4-channel volume control (basically the same as the Luxsin does in one box but cheaper and I think the miniDSP has better functions).
I can't find a good multi-channel preamp or volume control... :-(

So, my only viable option would be the Luxsin X9.

If you don't want to run the volume control of the miniDSP, and you don't want to add it after the analog preamp, then this piece of kit is quite useless... am I missing something?

There’s nothing complicated about it at all. The Rotel Integrated amp is just used for more than 1 set of speakers.

I use the miniDSP as the DAC, PreAmp, DSP, etc when listening to music (Item #2 & 3) from my response above. It’s just using two different set of speakers which are setup at different listening positions. One is the couch and the other is at my desk but each have different speakers using the same amp. Not many amps have A/B speaker option so people are stuck with one amp per set of speaker.

 

[jareinertson]

So I have a Marantz Model 30 and SACD 30n and would like to add a Minidsp Flex in between them to use as a Dirac box. To make this work, I'd have to rely on the combined ADC and DAC performance of the Flex, since the SACD 30n is under DRM lockdown.

What I'm wondering is whether the Flex' ADC stage is generally considered "good enough" to be inaudible with DSP included? Or would I likely get an audible improvement by using something like the Minidsp Adept for the analog conversion and then chaining that to the Flex?

I am doing something similar. I use a WiiM Pro + in the Tape monitor loop for my vintage Levinson analog preamp. Works fine providing room correction.

 

[rvsixer]

There’s nothing complicated about it at all.

 

[Keith_W]

I was thinking to use the miniDSP as DAC and DSP, and feed to a preamp for 4-channel volume control (basically the same as the Luxsin does in one box but cheaper and I think the miniDSP has better functions).

What's wrong with using the MiniDSP as a volume control?

 

[SoySalsaPicante]

What's wrong with using the MiniDSP as a volume control?

Some people are scared of digital volume controls, “forgetting,” their setting and suddenly going to full. The miniDSP, however, in my experience, drops to a quite low default volume if it loses memory of the previous setting.

 

[Keith_W]

Some people are scared of digital volume controls, “forgetting,” their setting and suddenly going to full. The miniDSP, however, in my experience, drops to a quite low default volume if it loses memory of the previous setting.

That's fair. There were reports of earlier versions of Roon going to 0dB on its own. A good solution is to use pro audio amplifiers, those usually have volume/gain controls built in, and they are really cheap. In fact, when you see how many features these amps have, you start to wonder why all amps don't have them. The downside is ugly aesthetics, cooling fans, and usually dreadful SINAD. I use two Yamaha PX10 pro audio amps for my woofers, each amp is bridged and produces a tonne of power. I modified them by replacing the standard fans with Noctuas and they are absolutely silent. And I hid them in the cabinet with ventilation holes cut out the back, so you can't see them.

 

[aikofan]

Some people are scared of digital volume controls, “forgetting,” their setting and suddenly going to full. The miniDSP, however, in my experience, drops to a quite low default volume if it loses memory of the previous setting.

I keep a passive analog volume control downstream of my miniDSP Flex as a limiter after I had some nasty incidents when it suddenly output noise at full volume at power on. It’s been several years since that happened, and it’s been smooth sailing since then, but I’m waiting for my PTSD to fade completely before I remove the attenuator.

 

[testp]

I keep a passive analog volume control downstream of my miniDSP Flex as a limiter after I had some nasty incidents when it suddenly output noise at full volume at power on. It’s been several years since that happened, and it’s been smooth sailing since then, but I’m waiting for my PTSD to fade completely before I remove the attenuator.

did it happen at minidsp end, like volume being full range, but should not have, or just user setup-up?

 

[aikofan]

did it happen at minidsp end, like volume being full range, but should not have, or just user setup-up?

It was the miniDSP's fault. It wasn't just the volume, but it was outputting screaming noise when it should have been silent with nothing playing.

But that was several years and several firmware updates in the past. Also, it seemed to be related to interrupting external power. I used to always turn off power at the surge protector when not using the equipment, and the Flex didn't seem to like external power being turned off and on, so I now keep the external power on all the time.

This is just one of several similar experiences with digital volume controls plugged straight into power amps, so my takeaway is that there's always a small chance that you'll get full power signal or noise unexpectedly, so be prepared.

 

[SoySalsaPicante]

It was the miniDSP's fault. It wasn't just the volume, but it was outputting screaming noise when it should have been silent with nothing playing.

But that was several years and several firmware updates in the past. Also, it seemed to be related to interrupting external power. I used to always turn off power at the surge protector when not using the equipment, and the Flex didn't seem to like external power being turned off and on, so I now keep the external power on all the time.

This is just one of several similar experiences with digital volume controls plugged straight into power amps, so my takeaway is that there's always a small chance that you'll get full power signal or noise unexpectedly, so be prepared.

And is it just me or do these things get crazy hot to the touch?