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xavier

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If you find subs that are linear up to 200Hz that can be done. Subs will play fine when positioned bellow bookshelves.

Most of the room impact happens below 200Hz so your idea will work pretty well assuming you get subs/bookshelves integration well.

Hmm ok, another option to think about :)

I know THX suggests 80 Hz crossover and there are a zillion threads about this, but just a 2019 recap, is it likely I can localize 100 Hz? 120? I guess I can just test, just that I'm in the process of moving countries and regrettably already sold my current stereo. I once tried to find the details of studies that determined 80 Hz was the sweet spot, but nothing detailed or technical came up. Just anecdotes saying 80 Hz was two standard deviations from the mean.
 

TimW

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I have a 2.2 system for TV and movies. I connect all of my HDMI devices to my TV and use the optical output of it to feed signal to a miniDSP DDRC-24. This is the 2x4 HD with Dirac Live upgrade. It acts as my DAC, preamp, and room correction. I use the TV to delay the video so that it syncs up with the audio. Two channels of the DDRC-24 go to my two subs and the other two go to a Yamaha P3500S amp that I got for $250.

I like this setup more than an AVR because I get great performance in the areas that matter to me without all the extra features I wouldn't use. Yes the low end miniDSP products like the 2x4 HD are sub par as far as DAC performance goes but in real world use I can't tell. The DAC performance probably isn't much worse than a standard AVR anyhow. What's more important to me is the quality of room correction and the amount of power available for loud Movie watching sessions. Instead of the limited, lackluster room correction that typically comes with affordable AVR's, the 2x4 HD has all of the DSP capabilities needed to properly integrate subwoofers into a system. You just have to know what you're doing. Add Dirac with the DDRC-24 and you have a killer automated room correction system. The Yamaha P3500S amplifier has much more power than a typical AVR would and has been measured here.

Some downsides are that it is complicated and takes more time to set up. Also you don't get a physical volume control or display with the miniDSP 2x4 HD. I never used the volume knob on my AVR so that part doesn't bother me. Having to hook up my laptop with a long USB cable to change settings is annoying though. Also not the most attractive setup but I don't care for AVR aesthetics either.
 

TimW

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Hmm ok, another option to think about :)

I know THX suggests 80 Hz crossover and there are a zillion threads about this, but just a 2019 recap, is it likely I can localize 100 Hz? 120? I guess I can just test, just that I'm in the process of moving countries and regrettably already sold my current stereo. I once tried to find the details of studies that determined 80 Hz was the sweet spot, but nothing detailed or technical came up. Just anecdotes saying 80 Hz was two standard deviations from the mean.
Audioholics discuss why 80 Hz was chosen in this video.
 

Blumlein 88

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Our ability to hear a timing difference between channels fades past 1500 hz with some caveats. It is maximum around 800 hz. We lose that again around 80 hz. So 80 hz and below timing issues will bother us less than a higher crossover. That is a good reason to put your crossover no higher than there.
 
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xavier

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I have a 2.2 system for TV and movies. I connect all of my HDMI devices to my TV and use the optical output of it to feed signal to a miniDSP DDRC-24. This is the 2x4 HD with Dirac Live upgrade. It acts as my DAC, preamp, and room correction. I use the TV to delay the video so that it syncs up with the audio. Two channels of the DDRC-24 go to my two subs and the other two go to a Yamaha P3500S amp that I got for $250.

I like this setup more than an AVR because I get great performance in the areas that matter to me without all the extra features I wouldn't use. Yes the low end miniDSP products like the 2x4 HD are sub par as far as DAC performance goes but in real world use I can't tell. The DAC performance probably isn't much worse than a standard AVR anyhow. What's more important to me is the quality of room correction and the amount of power available for loud Movie watching sessions. Instead of the limited, lackluster room correction that typically comes with affordable AVR's, the 2x4 HD has all of the DSP capabilities needed to properly integrate subwoofers into a system. You just have to know what you're doing. Add Dirac with the DDRC-24 and you have a killer automated room correction system. The Yamaha P3500S amplifier has much more power than a typical AVR would and has been measured here.

Some downsides are that it is complicated and takes more time to set up. Also you don't get a physical volume control or display with the miniDSP 2x4 HD. I never used the volume knob on my AVR so that part doesn't bother me. Having to hook up my laptop with a long USB cable to change settings is annoying though. Also not the most attractive setup but I don't care for AVR aesthetics either.

Nice setup! Good to read about someone running 2.2. Regarding amp power, I wasn't too worried for AVR considering the Denon I had in mind is rated at about 105 watts (8 ohm, 20 Hz - 20 kHz, 0.05% 2ch Drive) and it would have HPF from at least 80 Hz, maybe 100 Hz, easing the load. I could be wrong that this is enough though.

Regarding no volume knob, it would leave me a bit uneasy, although again this could be my own misconception of the functionality. Have you had issues regarding volume being erratic in any way? Blasting the amp, whilst the remote is nowhere to be found, or things like that?
 
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xavier

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Our ability to hear a timing difference between channels fades past 1500 hz with some caveats. It is maximum around 800 hz. We lose that again around 80 hz. So 80 hz and below timing issues will bother us less than a higher crossover. That is a good reason to put your crossover no higher than there.

What I'm wondering is how broad is the margin "around 80 hz", and if there is a paper or article citing studies I could read regarding how this number was determined. What leads me to this question is, for example, the video from Audioholics shared by @TimW which starts with the commentary on THX choosing 80 Hz, yet Gene then mentions 120,150 Hz as possible frequencies before being able to localize.

On multiple forums, I see this discrepancy in the frequency recommended (purely from localisation perspective, not the other advantages/disadvantages), and I wonder about how this was determined, aside from just testing it in one's system I guess, which I will be able to do once I'm set up again. I am aware that this number will vary at least slightly from person to person, but would be great to see data on the study that determined this. In the Audioholics video shared (I had watched it before), for example, Matt mentions anecdotaly that 80 Hz was two standard deviations below the mean where localisation stopped. Would be great to know what the mean was, number of people tested, etc...
 

TimW

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Nice setup! Good to read about someone running 2.2. Regarding amp power, I wasn't too worried for AVR considering the Denon I had in mind is rated at about 105 watts (8 ohm, 20 Hz - 20 kHz, 0.05% 2ch Drive) and it would have HPF from at least 80 Hz, maybe 100 Hz, easing the load. I could be wrong that this is enough though.

Regarding no volume knob, it would leave me a bit uneasy, although again this could be my own misconception of the functionality. Have you had issues regarding volume being erratic in any way? Blasting the amp, whilst the remote is nowhere to be found, or things like that?

I have not had any volume issues. The miniDSP is always powered on so there is no turn on/off pops and it remains at the last volume setting. Even after a power outage there was no issue with high volume at startup. However I did set my amp and subs to a lowish volume setting so that if the miniDSP sends full folume to them It shouldn't break anything. Also I use a Harmony Hub remote system so whenever the remote goes missing I can use my phone for control. I kind of miss having a digital display for volume but the porthole screen of the Marantz I had before was too small to make out from across the room anyway.
 

D700

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Denon AVR with some efficient speakers is great, inexpensive way to go for TV/HT. I like and have used several Denons and Marantz with a variety of Klipsch. TV especially is seldom good audio so the electronic room adjustment helps intelligibility a lot. Keep those ATCs and build a separate 2 channel system for critical listening. 1 sub each...why do you want or think you need dual subs? Every system I’ve ever done I’ve always had to keep bass output low, otherwise overwhelms the room.
 
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xavier

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I have not had any volume issues. The miniDSP is always powered on so there is no turn on/off pops and it remains at the last volume setting. Even after a power outage there was no issue with high volume at startup. However I did set my amp and subs to a lowish volume setting so that if the miniDSP sends full folume to them It shouldn't break anything. Also I use a Harmony Hub remote system so whenever the remote goes missing I can use my phone for control. I kind of miss having a digital display for volume but the porthole screen of the Marantz I had before was too small to make out from across the room anyway.

Yeah maybe I should be more open minded about the idea of no volume knob. I am leaning towards Denon though to start with, for convenience and budget also.
 
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xavier

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Denon AVR with some efficient speakers is great, inexpensive way to go for TV/HT. I like and have used several Denons and Marantz with a variety of Klipsch. TV especially is seldom good audio so the electronic room adjustment helps intelligibility a lot. Keep those ATCs and build a separate 2 channel system for critical listening. 1 sub each...why do you want or think you need dual subs? Every system I’ve ever done I’ve always had to keep bass output low, otherwise overwhelms the room.

The dual sub thought was to have a flatter frequency response rather than more output. Two quality small ones vs. one big. I'm moving to the UK so I was looking at BK subs. I've never tried dual subs, but I have in my house a pair of old Revox Symbol Bs, one is busted, and just to try I ran the single Revox speaker as a sub (it's a beast of a speaker). When I walked around the room, I could tell huge differences in bass. So from experience and from reading about room acoustics and recommendations, seems dual subs can be very useful.

Regarding ATCs, thanks for tip, however I've already committed to selling them. Don't want to cross the Atlantic with them, afraid they might get damaged. I did have sentimental attachment to them though, as I think they're very good, albeit very demanding. My Rotel amp would go into protection at parties.
 
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Krunok

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Our ability to hear a timing difference between channels fades past 1500 hz with some caveats. It is maximum around 800 hz. We lose that again around 80 hz. So 80 hz and below timing issues will bother us less than a higher crossover. That is a good reason to put your crossover no higher than there.

But does it really matter when you will be able to get timing right with the DSP?
 

D700

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The dual sub thought was to have a flatter frequency response rather than more output. Two quality small ones vs. one big. I'm moving to the UK so I was looking at BK subs. I've never tried dual subs, but I have in my house a pair of old Revox Symbol Bs, one is busted, and just to try I ran the single Revox speaker as a sub (it's a beast of a speaker). When I walked around the room, I could tell huge differences in bass. So from experience and from reading about room acoustics and recommendations, seems dual subs can be very useful.

Regarding ATCs, thanks for tip, however I've already committed to selling them. Don't want to cross the Atlantic with them, afraid they might get damaged. I did have sentimental attachment to them though, as I think they're very good, albeit very demanding. My Rotel amp would go into protection at parties.
I’ve found you almost always have more bass than you need, if using proper calibration. You may gave been hearing bass over emphasis from a corner as not enough bass in the other. SPL meter or app for your phone is your friend. Good luck!
 
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xavier

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I’ve found you almost always have more bass than you need, if using proper calibration. You may gave been hearing bass over emphasis from a corner as not enough bass in the other. SPL meter or app for your phone is your friend. Good luck!

Honestly I think two subs would work pretty well, to manage room modes and such. I may however start with one to first see how that works out. That at least gives me more motiviation to find the best position for one rather than jamming the quick fix first.
 

Krunok

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Honestly I think two subs would work pretty well, to manage room modes and such. I may however start with one to first see how that works out. That at least gives me more motiviation to find the best position for one rather than jamming the quick fix first.

Two subs are always better than one. More details you can find here.
 

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My preference in HT has been to opt for a stereo system. I admit you lose the surround effect but what you gain is the budget and space for two really good main speakers rather than five lacklustre ones. On balance, I prefer this combination, and all the more since music is my first priority.
My main speakers are quite massive Quad 2805s, with an additional B&W PV1d subwoofer and an Antimode 8033 dsp room eq unit. I cross over at 33 Hz with the main speakers run at full range. The electrostats are admittedly dipoles and hence generate fewer room modes so the biggest need for room eq is indeed with the sub. Even so my new rme adi 2 dac has some additonal eq potential and I will use that to equalize the bottom end of the main speakers as well. A final adition will indeed be a second sub for an even smoother sound over a wider area. But with the rme adi 2 I have exhausted my audio budget for quite a while.
 
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xavier

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My preference in HT has been to opt for a stereo system. I admit you lose the surround effect but what you gain is the budget and space for two really good main speakers rather than five lacklustre ones. On balance, I prefer this combination, and all the more since music is my first priority.
My main speakers are quite massive Quad 2805s, with an additional B&W PV1d subwoofer and an Antimode 8033 dsp room eq unit. I cross over at 33 Hz with the main speakers run at full range. The electrostats are admittedly dipoles and hence generate fewer room modes so the biggest need for room eq is indeed with the sub. Even so my new rme adi 2 dac has some additonal eq potential and I will use that to equalize the bottom end of the main speakers as well. A final adition will indeed be a second sub for an even smoother sound over a wider area. But with the rme adi 2 I have exhausted my audio budget for quite a while.

Sounds like a nice system. In your setup, are you losing the LFE channel from movies? Some people don't mind this, I was just wondering if you were aware and/or handling it somehow.
 

Willem

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I just use the full range stereo signal. The sub is connected from the speaker terminals of the power amplifier.
 
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xavier

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Unless your source is downmixing the LFE channel into stereo, which is usually not the case, you wouldn't be getting that channel. If it is being downmixed into stereo signal I believe you would face other issues such as reduced dynamic range. This doesn't bother most people, and possibly in your system it's the best scenario if your mains are being run full range, but just thought I'd mention just in case.
 

digitalfrost

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Hmm ok, another option to think about :)

I know THX suggests 80 Hz crossover and there are a zillion threads about this, but just a 2019 recap, is it likely I can localize 100 Hz? 120? I guess I can just test, just that I'm in the process of moving countries and regrettably already sold my current stereo. I once tried to find the details of studies that determined 80 Hz was the sweet spot, but nothing detailed or technical came up. Just anecdotes saying 80 Hz was two standard deviations from the mean.
It depends on the location of your sub, the crossover (Butterworth/LR) and the distance from the satellites.

I was definitely able to locate the sub no matter what I did. I listen in a desktop environment with KEF LS50. I have about 80cm - 1m stereo triangle. When I had the sub off to the side or even under the desk, it was always noticable.

I eventually built DIY subwoofers as stands for the LS50 - this solved 2 problems in one. I have the tweeters at ear height and my subwoofers in front of me, directly below the satellites.

Moving from 12dB filters to 24dB also made a massive improvement. "You can't locate a sub" is definitely wrong. Currently, I cross over at 100hz, since I can afford to now.
 
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