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Minidsp Flex Review (Audio DSP)

Rate this product:

  • 1. Poor (headless panther)

    Votes: 4 0.7%
  • 2. Not terrible (postman panther)

    Votes: 16 2.8%
  • 3. Fine (happy panther)

    Votes: 117 20.6%
  • 4. Great (golfing panther)

    Votes: 431 75.9%

  • Total voters
    568

Ultrasonic

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Yes, it would.
But, using 2 separate DACs (mains + sub) is not as easy, that creates a phase difference. It's not a difference in volume, ok (unless the DACs have a digital volume and you don't disable it).

Maybe Dirac can take care about that phase differences, I don't know.

The use of the digital version seems to have some unknown implications for me or maybe I'm simply over thinking :)

I would buy the analogue version but two DACs would work perfectly fine, and someone may have a higher quality DAC they specifically want to use for their main speakers and a cheaper one for their sub(s). Latency differences between the two DACs would be irrelevant, as they just add in to the bigger differences associated with the different positions of the sub(s) and main speakers, and that associated with the sub itself. These aren't managed by Dirac but can and should be based on measurements made in REW and then appreciate delays and crossover filters applied in the plugin.

Edit: differences in DAC volume also wouldn't matter as you already have unmatched outputs and will be adjusting sub gain to adjust, and ultimately EQ to the required combined response if sub plus main speakers.
 
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Hayabusa

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Unfortunately, there no way to enter IR codes in harmony products:(.
Only IR learning from existing remotes.
Logitech removed this feature 15 years ago.
The only way is to wait for Logitech to update their database.
Harmony has the codes for the SHD
 

antcollinet

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Yes, it would.
But, using 2 separate DACs (mains + sub) is not as easy, that creates a phase difference. It's not a difference in volume, ok (unless the DACs have a digital volume and you don't disable it).

Maybe Dirac can take care about that phase differences, I don't know.

The use of the digital version seems to have some unknown implications for me or maybe I'm simply over thinking :)
Why would it cause a phase difference (assuming both DACs are identical)?
 

vicenzo_del_paris

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Harmony has the codes for the SHD
As mentioned by rbachl in post #598,
The Flex is now is the Logitech database :)
I can now have everything automated the same way as when I was using the ddrc-24!
 

mike70

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Why would it cause a phase difference (assuming both DACs are identical)?

Well, I'm thinking in a balanced DAC for mains and in a cheaper DAC for sub ... So, they'll be different.
Maybe doesn't worth it ... if the DAC in the flex seems to be in a very good level.

In the other way ... we still don't know the price, maybe the flex digital + cheap topping is almost the flex balanced.
 

antcollinet

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Well, I'm thinking in a balanced DAC for mains and in a cheaper DAC for sub ... So, they'll be different.
Maybe doesn't worth it ... if the DAC in the flex seems to be in a very good level.

In the other way ... we still don't know the price, maybe the flex digital + cheap topping is almost the flex balanced.
Maybe - though I wouldn't expect that.
 

TheBatsEar

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Not to turn this thread to politics and kudos for MiniDSP for developing a good product, but I really wish a European company would offer something similar in 1K€ - 2 K€ price bracket.
That's how my uncle turns the mood sour at family festivities: "Not to turn this relaxed cake fest to politics, BUT THEM LIBERALS ..."
Every single time, like clockwork, after the first drinks have been poured. :cool:

Anyway, do we have pictures from the inside of the Flex yet? I wonder, is there space for a 12v to 5v converter and a RPi Zero 2?
 

5-pot-fan

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Can anyone confirm that the analogue version of the Flex will take input from a phono pre-amp and provide output through USB?
I have looked through the review and scanned every post on this thread, plus have read the manual (yes, it says it does), but I'm still looking for a positive confirmation, especially from anyone who has actually recorded something this way - eg from vinyl to a computer.
 

rbachl

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All versions of Flex have analog inputs. Digital Flex and unbalanced Flex have RCA inputs, balanced version of Flex have XLR input with a TRS jack. Therefore, it seems that the question is whether turntable phono can be connected to one of these inputs directly.

Flex can have the filters programmed for the RIAA equalization.
The biquad filter for RIAA equalization is included in an Excel sheet from miniDSP describing some advanced filter programming,
cf. https://www.minidsp.com/images/fbfiles/files/All_digital_coefs_v1-20101026.zip

While this solves the RIAA equalization, the signal levels and impedance of the phono output seems to be different from what is
expected for the RCA or XLR inputs in the Flex. Therefore it seems to be better to use a dedicated phono preamplifier.
 

Ultrasonic

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All versions of Flex have analog inputs. Digital Flex and unbalanced Flex have RCA inputs, balanced version of Flex have XLR input with a TRS jack. Therefore, it seems that the question is whether turntable phono can be connected to one of these inputs directly.

Flex can have the filters programmed for the RIAA equalization.
The biquad filter for RIAA equalization is included in an Excel sheet from miniDSP describing some advanced filter programming,
cf. https://www.minidsp.com/images/fbfiles/files/All_digital_coefs_v1-20101026.zip

While this solves the RIAA equalization, the signal levels and impedance of the phono output seems to be different from what is
expected for the RCA or XLR inputs in the Flex. Therefore it seems to be better to use a dedicated phono preamplifier.

The question was about using a 'phono preamp' which to me implies one that carries out the RIAA filtering.
 
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mike70

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The question is different ... you can use the USB port as output to digitalize the analog input in a computer?

The manual say yes, but I think 5-pot-fan is wondering if anyone has tested that feature.
 

Sharpi31

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The analogue line in on the Flex appears as a source in Volumio (I’ve not tested), so I’d expect it to be available on Win 10/11 too.

Edit: This might be wrong - it looks like the 4x output channels are routed back to the PC. So it could still work if the Flex had analogue input selected and a config that routed the analogue input directly to outputs. Don’t take my word for this - I’m not sure. Will try to test and confirm.
 

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Ultrasonic

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The analogue line in on the Flex appears as a source in Volumio (I’ve not tested), so I’d expect it to be available on Win 10/11 too.

The question is about the USB output though.

@mike70 has restated the real question here. (I think the answer is yes but it would be good if someone could actually confirm this.)
 

rbachl

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The question was about using a 'phono preamp' which to me implies one that carries out the RIAA filtering.
Oooops, you are right, I was interpreting the question wrongly.

So it is about the USB output. For that matter, the type of input is probably not relevant at all.
Therefore, I was checking now the Flex USB output with a source connected to Flex SPDIF.
With Linux, I could not get the signal from Flex USB.

When checking the same setup with RME ADI-2 pro, there is a signal at the USB port that I can record.

Therefore, either I am making some mistake, or Linux support of the Flex has some problem, or Flex USB port is really not delivering any signal.
 

mike70

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Maybe some configuration is needed in Flex ... remember that USB port also is used as input.

If the port is USB audio class 2 must work flawless in Linux
 

rbachl

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Maybe some configuration is needed in Flex ... remember that USB port also is used as input.

If the port is USB audio class 2 must work flawless in Linux

1645829838134.png

Ok, I made some small progress.
I have tried all configurations for Flex which are available in PulseAudio.
Input configurations from Flex are all available as "Multichannel Input".
With this input configuration, I see two input devices as shown in the figure above.
On the "Monitor of miniDSP Flex DL Digital Stereo (IEC958)", I have not seen a signal.
On the "miniDSP Flex DL Multichannel", the signal is available, but with very low volume only.
I am listening with very low volume now, and it is probably including the scaling with the volume knob.
The scaling was so low that I did not see any signal at all before.
 

mike70

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View attachment 189146
Ok, I made some small progress.
I have tried all configurations for Flex which are available in PulseAudio.
Input configurations from Flex are all available as "Multichannel Input".
With this input configuration, I see two input devices as shown in the figure above.
On the "Monitor of miniDSP Flex DL Digital Stereo (IEC958)", I have not seen a signal.
On the "miniDSP Flex DL Multichannel", the signal is available, but with very low volume only.
I am listening with very low volume now, and it is probably including the scaling with the volume knob.
The scaling was so low that I did not see any signal at all before.
I don't have my Linux computer at hand to check ... but maybe you need to setup audio to 4 channels.

You can try the alsamixer command in a terminal. If the command doesn't exists, you need to install the alsa-utils package.
 
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Ultrasonic

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I know nothing about Linux support but for info. with the SHD it's possible to see the USB return signal using REW and setting the SHD as an input device as well as an output. On the miniDSP forum I've seen someone posting about having done the same with a Flex.
 

5-pot-fan

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The analogue line in on the Flex appears as a source in Volumio (I’ve not tested), so I’d expect it to be available on Win 10/11 too.

Edit: This might be wrong - it looks like the 4x output channels are routed back to the PC. So it could still work if the Flex had analogue input selected and a config that routed the analogue input directly to outputs. Don’t take my word for this - I’m not sure. Will try to test and confirm.
Thank you for being willing to try! My input would be via RCA from my phono pre and output would be via USB into a Windows PC (but a Linux or Mac ought to work as well.
 

abdo123

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Thank you for being willing to try! My input would be via RCA from my phono pre and output would be via USB into a Windows PC (but a Linux or Mac ought to work as well.
This should work fine. I digitized my vinyls for a long time this way.
 
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