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miniDSP 2.1 solution finder

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dom_st

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And just today, came the new REW update, for the flex itself.
1707149482003.png


How does it sound? Still a little strange, or is everything just singing?

Actually i am still playing around.

Today with my left speaker, moved it from where it was, further away from the wall around 80cm from speaker to wall and from there closer towards the left wall, but not all the way (stopped at 0.9m) to the wall as bass became a bit prominent as well.

1707150776289.png


And then turned it in towards listening position etc. Just to see how the room reacts. tl/dr: the area around 80 and180Hz is the most problematic and no matter what i do it kinda doesn´t change by much.

This picture below is messy but it kinda represents a few learning's about my room and how speaker position influences the measured curve.
So moving the left speaker closer to the left wall, increases bass to a point that you can ignore the bass boost switch.
No matter what i do, i seem to have this room mode at my listening position.
There i a specific position (some green /blue graph) that improves the drop at 100Hz by a few dB, but it comes with a cost -> another drop at around 150Hz.
I think the position where the speaker was in the beginning, wasn´t too bad.

1707149661592.png
 
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dom_st

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I think i have a position right now that i am satisfied with (sound wise), for my speakers and my sub i guess all is good.
No filters active right now, this is left and right together xo at 60Hz, sub was not measured here, but it´s running at -24dB (any other stetting it´s way too loud, still don´t get it why that is).
Don´t ask me what happend to the high in this measurement, maybe some background noise as the window was open. As in no other measurment i did saw something like that.

1707154194854.png


I also got the the dirac license to see if it could help somehow. Only tested it once so far. But i think it´s not improving anything that can´t be done in REW.
 

D!sco

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sub was not measured here, but it´s running at -24dB (any other stetting it´s way too loud, still don´t get it why that is).
Could it be that you're using a line in instead of a preamp in? It could be running full volume instead of the -40 or so dB the miniDSP is set to by the volume control.

True that you can do anything in REW and RePhase that DIRAC can, but it's much easier. DIRAC can help with phase and the many small issues that take too many EQ bands.
 
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dom_st

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as i have the balanced version, i have a TS to RCA adapter, where i have a Y-adapter cable going into the line in of the sub.

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I kind of tried to do what they recommend here. I used the TS as they say either way only tip and sleeve is connected? maybe that´s my problem.
1707155413493.png


This is how it measured now with sub. No EQ anywhere.

1707155519806.png
 
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dom_st

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Or i need to solder my own suitable cable, would prefer to buy something suitable. But it seems there is no such thing available. Would be nice if minDSP would provide such a cable.
By the way, does it make sense to EQ the combined measurement of the l and r channel?
For the XO it makes sense to link the channels, as the XO is the same for both.
But for the PEQ?
1707156688724.png
 

D!sco

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If you want more help, please post the phase and distortion data. I think there are a few things you can do to clean up these dips.

When setting up stereos, I like to keep everything equal distance. 1m from left to right, 1m from listener to each speaker, for example. Knowing the dispersion spread can help, especially if it's very consistent. Then you can pick a better informed distance between the two speakers so they don't cancel each other, and/or how far they are from the wall. Often, there has to be overlap, so there's either some cancellation at the listening position, or extra reflections from the walls. These are the dips you are struggling with, and I suspect some may be resolved by pulling the speaker further from the wall (though this may not be reasonable) and rotating them inward, towards your listening position.
I tried drawing a diagram but I'm hitting the limitations of my software. It doesn't want to rotate my squares. o_O

Regarding the sub, it is receiving full voltage and no preamp amplitude reduction. Shame, but it means the way you are reducing the volume is the right thing already. You may only need one of the channels, instead of a Y-cable. That could help immediately. The DSP is already sending both left and right to the one output, it doesn't need to be split. The only problem would be if changing the miniDSP volume no longer controls the volume of the subwoofer.

By the way, does it make sense to EQ the combined measurement of the l and r channel?
I would EQ left and right issues that are only for the specific speaker. One channel has a dip the other doesn't, for example. Otherwise you can use global EQ to correct issues with both speakers easily. I would only avoid equalizing the range that the sub will cover. No point wasting that space when it will go in the sub's EQ settings.

Here is an example of my highly compromised apartment setup. The green and blue are left and right. The red is L+R, brown is adjusted to level match each channel. In yellow, you can see where the left and right have opposing dips and peaks, which cancel slightly and level out. In purple, you can see where the upper midrange overlaps and cancels, despite being equal. This is why a combined measurement is important.
HiVi 3.1 Recliner EQ Graph.png

And here is my EQ correction:
EQ is magic.png

My old, crowded apartment these measurements were taken in. The star represents the measurement location and the ideal listening position. Not ideal was the distance to walls, both myself and the speakers. They were also rotated to point directly at the star, which isn't pictured.
1707150776289.png
 
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dom_st

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If you want more help, please post the phase and distortion data.

When setting up stereos, I like to keep everything equal distance. 1m from left to right, 1m from listener to each speaker, for example.
It kinda is like it right now, classic triangle.
Left is blue
Right is green
red is L+R
Again, no equalizing done yet.

As you can see the speakers are kinda level matched at around 75dB, but the red combined one is a few dB higher. Should now be reduced to match the 75dB? by reducing the gain in miniDSP as i did with the sub?

Sometimes the red line makes sense, sometimes it´s just weird. As you explained, dips and peaks eventually neutralize each other. Sometimes red follows the green, sometimes the blue line.
1707163986171.png


I see you are fading out the highs pretty soon , starting slowly at around 1kHz.
 

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D!sco

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It kinda is like it right now, classic triangle.
That explains why your measurements are so good without correction.
Should now be reduced to match the 75dB? by reducing the gain in miniDSP as i did with the sub?
Yes. The button should be something like "Align SPL" in the tab "All SPL".
Sometimes the red line makes sense, sometimes it´s just weird
You can't always fix the weird without changing your room or treating the hell out of it.
What you could try is equalizing L and R individually, then checking L+R like here. You can assign different colors and align them on the graph to compare. Anything that doesn't get solved maybe can't be solved. No speaker or room is perfect.
I see you are fading out the highs pretty soon , starting slowly at around 1kHz.
It's not all that different from the Harman curve, but it is a little more extreme. My hearing can be sensitive in the upper frequencies, so this is my way of preserving them while still playing quite loud sometimes. Those SPL levels are accurate in the REW graphs, but only because I lived on a very busy street and needed real distortion measurements. I had to wear hearing protection.
 
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dom_st

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i have now eq´ed left and right and the bass.
And slightly increased the xo to prevent the boost at 70-80Hz becoming larger.

Just don´t get the allign SPL button, as it gives me an error all the times no matter what measurements i select. But i guess it´s ok as it is, right now.
1707454873444.png
 

D!sco

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Can’t do it with the sub I guess. Just reading the error, you would need the center to be 60hz. I did full system sweeps, so 20hz to 20kHz, sub included (but not a separate measurement.) This allowed me to compare L, R and L+R without the last one floating above the other two. If the sub is set up right, just leave it in, remeasure, and SPL average. Huge learning curve to REW.

I’m guessing your native language is German, or something near that area based on your speaker choice. Does REW have a decent German guide? It’s spectacular in English, but I know how confused I feel when using translation software or my bad memory when trying to understand German audio posts. The terminology of two esoteric groups coming up with different ways of saying the same thing can be a little unbearable.
 
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dom_st

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Yeah just didn't get the message, but now it seems to make sense, thanks again!
 
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dom_st

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I removed the sub and now it works, thank you for the suggestion.
Was just busy throughout the week, so not much time to answer.
yellow is now l+r+sub i think there is still some room for improvement. but i guess it´s as you said, nothing is perfect ;-)
But i might turn my whole listening area by 90 degrees and need to remeasure everything again, haha.:D

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D!sco

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That bass dip at 50-60 could be phase, which has it's own graph. I always fix phase by opening up a video game and smacking something, but you can see if the squiggles line up in REW just fine.
80-120 is probably unavoidable, and I see it all the time. Probably a reflection from behind the speaker.

This has to be one of the best setups I've seen.
 
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