Minidsp Flex Review (Audio DSP)

[glc650]

I have looked at your post that you linked and I still cannot find a proper TRS to RCA adapter or cable. Does that mean I have to make one?

Doesn't minidsp sell them? I think when you order the flex there is even a drop down to buy some?

 

[antcollinet]

I have looked at your post that you linked and I still cannot find a proper TRS to RCA adapter or cable. Does that mean I have to make one?

Yeah - that is a bit of a problem. Most TRS to RCA are intended for stereo applications, not balanced. I've never actually seen one you can buy.

I made my own by cutting a standard RCA and soldering on TRS connectors.

 

[BearWant]

Yeah - that is a bit of a problem. Most TRS to RCA are intended for stereo applications, not balanced. I've never actually seen one you can buy.

I made my own by cutting a standard RCA and soldering on TRS connectors.

I have tried to read all the prior conversations about this, but have only managed to confuse myself further. Sorry newbie here. This is my first post. Hi all! Does this only apply to the inputs. Or is there also controversy surrounding the use of the optional adapter cable from MiniDsp going from the Flex balanced output to RCA? If the latter is the case, has there been a cable solution identified from a vendor, or I am stuck trying to make a frankencable. I do not think I have faith in my ability to do this.

Anymore whisperings of that possible "hybrid" solution. I have one professional power amp which is balanced, but would also like to output to a vintage Pioneer unit.

 

[staticV3]

You can use a TRS to RCA cable as described in miniDSP's guide to connect RCA Amplifiers to the Flex Balanced's TRS outputs: https://support.minidsp.com/support...ectivity-which-trs-to-rca-cable-should-i-use-

Using the same cable on the Flex Balanced's TRS inputs however is not recommended.

 

[antcollinet]

You can use a TRS to RCA cable as described in miniDSP's guide to connect RCA Amplifiers to the Flex Balanced's TRS outputs: https://support.minidsp.com/support...ectivity-which-trs-to-rca-cable-should-i-use-

Using the same cable on the Flex Balanced's TRS inputs however is not recommended.

It'll work on inputs too. But Minidsp have measured a drop in Sinad when driving balanced inputs with unbalanced sources. It's not a big enough issue for most analogue sources.

But on inputs you can also use a TS to RCA connector which *is* readily available as a typical mono cable.

Simple wiring for both inputs and outputs.

Tip of TRS to pin of RCA
Sleeve of TRS to shield/ground of RCA.

MiniDSP's arrangement using a two core screened cable can provide some noise immunity in some circumstances, but is not necessary for basic functionality (I am using a simple single core screened wire)

 

[BearWant]

Thank you both! This puts me at ease. I think I will be ordering the balanced Flex.

 

[thenamelessone7]

Looks like they should be offering another configuration: 2 balanced outs + 2 unbalanced outs. That would solve a lot of problems because I think the major use case is 2 speakers + 1/2 subwoofers (which are often powered).

 

[BearWant]

Looks like they should be offering another configuration: 2 balanced outs + 2 unbalanced outs. That would solve a lot of problems because I think the major use case is 2 speakers + 1/2 subwoofers (which are often powered).

Agreed

 

[RHO]

Agreed

?
What is wrong with just using the hot output to create an SE signal from the balanced outputs?
There's no reason to build one with 2 balanced and 2 SE outputs, because there already exists one: the one with the 4 balanced outputs.

 

[MCH]

?
What is wrong with just using the hot output to create an SE signal from the balanced outputs?
There's no reason to build one with 2 balanced and 2 SE outputs, because there already exists one: the one with the 4 balanced outputs.

Agreed, but i also feel the pain of the fellow members. Rca connectors are fool proof but tsr are not, and this thread is a testament of it. At least they could throw a couple of adaptors in the box, or a note "if in doubt, go to asr and ask tonycollinet"

 

[antcollinet]

Agreed, but i also feel the pain of the fellow members. Rca connectors are fool proof but tsr are not, and this thread is a testament of it. At least they could throw a couple of adaptors in the box, or a note "if in doubt, go to asr and ask tonycollinet"

To misquote Tom Hanks in Apollo 13

"It's not a miracle - I just went there"

 

[RHO]

Agreed, but i also feel the pain of the fellow members. Rca connectors are fool proof but tsr are not, and this thread is a testament of it. At least they could throw a couple of adaptors in the box, or a note "if in doubt, go to asr and ask tonycollinet"

Maybe some instructions in the owners manual could also help.

 

[Dan B]

From the study you linked to:

• There exists in this study no statistically significant evidence supporting the audibility of phase distortion in the musical samples provided, using the all-pass filter implementations chosen by the researchers.

Are you saying that you can hear a difference with music? If so this is an extraordinary claim that contradicts the study and it would be helpful if you could provide some evidence for this claim such as a level matched blind ABX test.

Check out this Audioholics review of what happened when they changed the crossover of a high end speaker to one using phase coherent FIR filters. Gene Dellasalla, the head of Audioholics, said he was skeptical that phase coherence based on papers he had read, but after listening to the difference as they switched back and forth he called FIR filters a "game changer", achieving "immediacy to the sound", "better imaging", and the "utmost accuracy and lifelike sound".

Ignore my opinion, watch the Audioholics 11:57 minute review here.

Do you think Gene Dellasalla was imagining things?

They used an expensive professional processor by Marani to do the FIR crossover filters, but the miniDSP Flex can do the same thing.

 

[staticV3]

as they switched back and forth he called FIR filters a "game changer", achieving "immediacy to the sound", "better imaging", and the "utmost accuracy and lifelike sound".

Those impressions are worthless unless backed up by double-blind testing and his resulting confidence score. Yeah placebo is a real killjoy.

 

[antcollinet]

Check out this Audioholics review of what happened when they changed the crossover of a high end speaker to one using phase coherent FIR filters. Gene Dellasalla, the head of Audioholics, said he was skeptical that phase coherence based on papers he had read, but after listening to the difference as they switched back and forth he called FIR filters a "game changer", achieving "immediacy to the sound", "better imaging", and the "utmost accuracy and lifelike sound".

Ignore my opinion, watch the Audioholics 11:57 minute review here.

Do you think Gene Dellasalla was imagining things?

They used an expensive professional processor by Marani to do the FIR crossover filters, but the miniDSP Flex can do the same thing.

Did he test blind or sighted. If sighted he may well have been subject to confirmation bias, expectation bias etc.

No-one is immune - it is how our brains work.

 

[Dan B]

Those impressions are worthless unless backed up by double-blind testing and his resulting confidence score. Yeah placebo is a real killjoy.

Perhaps it's just not worth checking out without a structured, certified double-blind test that you can participate in, which may never happen. Just ignore it.

 

[Dan B]

Did he test blind or sighted. If sighted he may well have been subject to confirmation bias, expectation bias etc.

No-one is immune - it is how our brains work.

Do you insist on a certified double blind test whenever you listen to new audio equipment? Is there any point in listening and evaluating any new audio equipment, say at a high end audio store, without a certified double blind test?

 

[dublinthedog777]

Just got the balanced version and can not sum my L and R channels for the subwoofer, and appears to be some kind of phase error as stereo image is no longer there and voices seem to coming from two directions until I invert one of the speakers. Old dac sounds perfectly fine. No returns, made in China. My mistake.

 

[levimax]

Do you insist on a certified double blind test whenever you listen to new audio equipment? Is there any point in listening and evaluating any new audio equipment, say at a high end audio store, without a certified double blind test?

The problem is unless the equipment you are comparing is level matched and blind it is not a useful test.

 

[antcollinet]

Do you insist on a certified double blind test whenever you listen to new audio equipment? Is there any point in listening and evaluating any new audio equipment, say at a high end audio store, without a certified double blind test?

When I'm listening to music, I'm not trying to make a definitive claim that a particular characteristic of that music is audible. Or not. I'm just enjoying music.

If I'm evaluating new kit, I'll short list that kit based on measurements. If I listen to kit (particularly electronics), it'll only be to ensure there is nothing fundamentally broken about the way it performs in my room/environment. I'll not be expecting to hear significant differences with what I have now, except where measurements tell me I might (eg power). Speakers a slightly different issue. But again I'll be listening for something not working in my room, that doesn't gel with the measurements.

Most importantly - if I'm evaluating new kit I'm only doing it for *me*. I'm not going to try to convince others that what I (think) I hear is correct. That they should buy the same kit because I think it sounds great.

On the other hand.
If I'm trying to provide evidence that Phase shift is audible I can't do it with sighted listening tests because everyone with any knowledge of psychoacoustics knows that my (like everyone else's) ear/brain is subject to unconcious bias. We can only prove a difference can be heard by doing it blind and controlled.

Especially when all the other published information doesn't point towards audibility. In that case I am making a claim that requires a high level of support (evidence)