REW - sending LF signal problem (Right and sub are playing but not left speaker?)

lovinthehd

lovinthehd

Audioholic Jedi
The problem with closing ports is that the box size will be wrong, and unless you know the T/S parameters of the driver you won't know F3 unless you measure it. Also for a lot of speakers F3 will be far too high after port closure. The second option still leaves you with the wrong slopes as you have a second order and not fourth order high pass.

I guess the point is essence is that a crossover has to be designed case by case for optimal results. You actually could make a really good case for speakers and sub to be designed and sold as a unit. What we have now is chaotic and hit and miss. Unfortunately usually miss.
I'm talking about utilizing a crossover in a device like an avr/pre-pro, not the speaker itself, when applying crossover slope.

While we can't always have your own custom tl enclosures...is it usually miss in reality or just not your preference?
 
TLS Guy

TLS Guy

Seriously, I have no life.
I'm talking about utilizing a crossover in a device like an avr/pre-pro, not the speaker itself, when applying crossover slope.

While we can't always have your own custom tl enclosures...is it usually miss in reality or just not your preference?
It has nothing to do with TL speakers, although their roll off is second order. The point is AVRs are all a one design crossover, with only the frequency alterable. So it is the very essence of an off the shelf crossover. You I'm sure know where that gets you.

So for optimal results the crossover must be designed to the speakers, or, and this is what I'm doing for the system my wife wants in the great room of our new home. I have designed the speakers to the crossover. Its in in wall system, including the sub.
 
lovinthehd

lovinthehd

Audioholic Jedi
It has nothing to do with TL speakers, although their roll off is second order. The point is AVRs are all a one design crossover, with only the frequency alterable. So it is the very essence of an off the shelf crossover. You I'm sure know where that gets you.

So for optimal results the crossover must be designed to the speakers, or, and this is what I'm doing for the system my wife wants in the great room of our new home. I have designed the speakers to the crossover. Its in in wall system, including the sub.
No, I'm not sure where that gets me, why I'm asking you. Doesn't answer the question in the way I was thinking at least. AVRs aren't all the same I don't think, have seen some mentions of those with adjustable slopes but rare indeed. Why not just seal the ported speakers when working out a good crossover with them and subs? Why would that not work with the assumption of most avr slopes? Explain this for the OP, not me.
 
TLS Guy

TLS Guy

Seriously, I have no life.
No, I'm not sure where that gets me, why I'm asking you. Doesn't answer the question in the way I was thinking at least. AVRs aren't all the same I don't think, have seen some mentions of those with adjustable slopes but rare indeed. Why not just seal the ported speakers when working out a good crossover with them and subs? Why would that not work with the assumption of most avr slopes? Explain this for the OP, not me.
No, I'm not sure where that gets me, why I'm asking you. Doesn't answer the question in the way I was thinking at least. AVRs aren't all the same I don't think, have seen some mentions of those with adjustable slopes but rare indeed. Why not just seal the ported speakers when working out a good crossover with them and subs? Why would that not work with the assumption of most avr slopes? Explain this for the OP, not me.
You may be right that there are AVRs with adjustable slopes, but I have never heard of one. As far as I know AVRs all follow the THX spec of 12 db high pass and 24 db low pass. If you know one that is different I would be very interested. I'm not saying there isn't but I don't know of it.

As I explained sealing the port of a ported speaker is not the answer. For one thing the driver is probably optimized for a ported design. If it is bookshelf then the F3 has a good chance of ending up too high. More importantly the optimal box for a driver sealed is universally smaller than the optimal ported box. If the box is too large, then Q rises and that means boomy.

In fact getting really accurate well defined bass is one of the most difficult challenges in audio. I have wrestled with it for over 60 years now. For classical music it is crucial. For music of the baroque a well defined damped bass is essential, or it sounds laughable and elephantine. For the symphony orchestra having articulate but powerful bass on the lower strings, makes it sound like live. For Wagner, in particular, the hypnotic bass line must be reproduced accurately. Realistic piano reproduction sounds simply awful with an inaccurate resonant bass. For organ music, and especially Bach, the pedal line must articulate clearly with real definition.

I think the issues discussed are why a lot, if not the vast majority of classical music listeners forsake subs and bass management as it is currently conceived.

Pop and rock largely have a synthetic contrived bass before you start, so the issues are different.
 
everettT

everettT

Audioholic Spartan
As for br
You may be right that there are AVRs with adjustable slopes, but I have never heard of one. As far as I know AVRs all follow the THX spec of 12 db high pass and 24 db low pass. If you know one that is different I would be very interested. I'm not saying there isn't but I don't know of it.

As I explained sealing the port of a ported speaker is not the answer. For one thing the driver is probably optimized for a ported design. If it is bookshelf then the F3 has a good chance of ending up too high. More importantly the optimal box for a driver sealed is universally smaller than the optimal ported box. If the box is too large, then Q rises and that means boomy.

In fact getting really accurate well defined bass is one of the most difficult challenges in audio. I have wrestled with it for over 60 years now. For classical music it is crucial. For music of the baroque a well defined damped bass is essential, or it sounds laughable and elephantine. For the symphony orchestra having articulate but powerful bass on the lower strings, makes it sound like live. For Wagner, in particular, the hypnotic bass line must be reproduced accurately. Realistic piano reproduction sounds simply awful with an inaccurate resonant bass. For organ music, and especially Bach, the pedal line must articulate clearly with real definition.

I think the issues discussed are why a lot, if not the vast majority of classical music listeners forsake subs and bass management as it is currently conceived.

Pop and rock largely have a synthetic contrived bass before you start, so the issues are different.
Here is an inexpensive one
https://emotiva.com/collections/processors/products/mc-700

"Flexible quadruple bass management, with 12dB or 24 dB per octave crossover filters, configurable in precise 5 Hz steps below 80 Hz (and 10 Hz steps above 80 Hz),"
 
moves

moves

Audioholic Chief
I have a problem... I connected the minidsp and can send test signals VIA usb from a laptop.... my other computer is connected to the AVR via optical and when I send music, no LF goes to the subwoofer... same thing with netflix, t.v. and blu ray...

When I remove the Minidsp the sub gets signal from everything above so it's not the connection of the peripherals. It seems to be something in the minidsp that is not working properly...

Does someone have any ideas?

Speakers are set to small with a 200Hz crossover in the AVR ( I can't turn off the crossover in the AVR) I've tried playing with this and nothing.

I've also tried setting the lowpass in the minidsp from 1000 to 80 Hz and nothing.

As I said, the test tone that is plugged directly into the minidsp via USB is sending signal.


EDIT***** NVM I figured it out... i had the input tab on the mini set to USB... when I changed it to analogue, I got LF signal from t.v. netflix and Blu-Ray.... Sorry guys... I am learning.

However, Another question..

When is it safe to unplug the usb from the mini? I don't see an eject USB on the computer... just pull it out?


Also, what should I put the crossover at in the AVR? 200Hz?

Should I set the lowpass in the mini to 80 or just bypass it?
 
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everettT

everettT

Audioholic Spartan
Why aren't you connecting thru avr with rew? Also have you gone threw the manual throughly? IMHO you are too far ahead in the process, as it took me close to a week to complete the setup with desired results. If you are using the minidsp with no idea of function you can damage your gear easily. DO NOT plug the minidsp untill you are fully ready to program it. Also you might want to post here as well

https://www.minidsp.com/forum/minidsp-for-newbies
 
moves

moves

Audioholic Chief
Why aren't you connecting thru avr with rew? Also have you gone threw the manual throughly? IMHO you are too far ahead in the process, as it took me close to a week to complete the setup with desired results. If you are using the minidsp with no idea of function you can damage your gear easily. DO NOT plug the minidsp untill you are fully ready to program it. Also you might want to post here as well

https://www.minidsp.com/forum/minidsp-for-newbies
I feel that I am ready to program it. I am not making huge changes... played with the inout and output gain a touch but that's about it as well as the crossovers. I don't see any change.

The manual said to plug the mini in VIA USB. I've read the manual many times and followed step by step instructions. Not sure what is wrong with sending the signal VIA USB directly into the mini is wrong?

When you configured yours, you only used the USB for configuration and not for sending test tones VIA REW? This means you had 2 computers connected to your system? This is what I have because a computer needs to be connected to the mini VIA USB for configuration.

Regarding unplugging the USB... when is it safe to unplug it?
 
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everettT

everettT

Audioholic Spartan
I just send the sweeps thru REW, as that's the why I learned and was told that its easier and safer. I have the regular 2x4 with two subs and two crown 2500series amps.

Also the reason I said to play with rew first as it helps understanding the processes. Taking good clean measurements are imperative to programming any eq.

As far as removing the usb, I'd power off all gear, wait a few minutes then do it. I'm overly cautious lol
 
moves

moves

Audioholic Chief
I just send the sweeps thru REW, as that's the why I learned and was told that its easier and safer. I have the regular 2x4 with two subs and two crown 2500series amps.

Also the reason I said to play with rew first as it helps understanding the processes. Taking good clean measurements are imperative to programming any eq.

As far as removing the usb, I'd power off all gear, wait a few minutes then do it. I'm overly cautious lol
Overly cautious is always good. There should be a "dismount button" in the mini interface for the USB but there is not, unfortunately.

So then you only use the USB to configure the mini... You send REW signals through the AVR I can try that. The manual says that it is best to send the test signals directly to the mini as the AVR often sets lowpass filters that cannot be bypassed (this is my case).


Oh and also, do you power off your Crowns after every use? I have mine set to sleep (5 min). but now with the minidsp, there is a "turn on and off" sequence that should be followed...

manual says when turning on, start with turning on "pre amp and mini" then power amps.

when turning off - turn off power amps first then pre amps etc.
 
everettT

everettT

Audioholic Spartan
Overly cautious is always good. There should be a "dismount button" in the mini interface for the USB but there is not, unfortunately.

So then you only use the USB to configure the mini... You send REW signals through the AVR I can try that. The manual says that it is best to send the test signals directly to the mini as the AVR often sets lowpass filters that cannot be bypassed (this is my case).
Correct. I'd enter the biquads, disconnect and connect avr and subs amps. Run sweep, disconnect adjust biquads repeat
 
moves

moves

Audioholic Chief
Correct. I'd enter the biquads, disconnect and connect avr and subs amps. Run sweep, disconnect adjust biquads repeat
Interesting and good to know. I've edited my post above with a power on off question.
 
lovinthehd

lovinthehd

Audioholic Jedi
You may be right that there are AVRs with adjustable slopes, but I have never heard of one. As far as I know AVRs all follow the THX spec of 12 db high pass and 24 db low pass. If you know one that is different I would be very interested. I'm not saying there isn't but I don't know of it.

As I explained sealing the port of a ported speaker is not the answer. For one thing the driver is probably optimized for a ported design. If it is bookshelf then the F3 has a good chance of ending up too high. More importantly the optimal box for a driver sealed is universally smaller than the optimal ported box. If the box is too large, then Q rises and that means boomy.

In fact getting really accurate well defined bass is one of the most difficult challenges in audio. I have wrestled with it for over 60 years now. For classical music it is crucial. For music of the baroque a well defined damped bass is essential, or it sounds laughable and elephantine. For the symphony orchestra having articulate but powerful bass on the lower strings, makes it sound like live. For Wagner, in particular, the hypnotic bass line must be reproduced accurately. Realistic piano reproduction sounds simply awful with an inaccurate resonant bass. For organ music, and especially Bach, the pedal line must articulate clearly with real definition.

I think the issues discussed are why a lot, if not the vast majority of classical music listeners forsake subs and bass management as it is currently conceived.

Pop and rock largely have a synthetic contrived bass before you start, so the issues are different.
Not much of a classical fan, just doesn't do much for me compared to other genres. What work of Wagner has a hypnotic bass line, tho? That sounds like it might be interesting.
 
moves

moves

Audioholic Chief
Why aren't you connecting thru avr with rew? Also have you gone threw the manual throughly? IMHO you are too far ahead in the process, as it took me close to a week to complete the setup with desired results. If you are using the minidsp with no idea of function you can damage your gear easily. DO NOT plug the minidsp untill you are fully ready to program it. Also you might want to post here as well

https://www.minidsp.com/forum/minidsp-for-newbies
I've been experimenting a bit with running REW directly into the mini VIA USB and seems to be working fine. I just had to assign the audio output from the laptop to the minidsp. From there, I would just toggle the input tab's input selector on the minidsp plugin back to analogue.. (i.e. the AVR). This seems to save a step compared to running a sweep, disconnecting, configuring, re-connecting.
 
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