Official Rythmik Audio Subwoofer thread - Page 931 - AVS Forum | Home Theater Discussions And Reviews
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post #27901 of 30660 Old 02-15-2017, 12:25 PM
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Originally Posted by Schrodinger23 View Post
I'm confused now. Can't you use the Rythmik subs without any DSP? If not then I am really confused why Dave would say this. I know that you can do the PEQ stuff, but you also don't have to mess with those knobs.
No, I'm not aware of any "pure direct" mode.
If you set the PEQ to 0db, it won't modify the numbers (the part that actually matters), but it's still working in the digital domain.

I suspect he meant that the servo inherently corrects certain things that would otherwise need to be corrected with EQ. It also corrects some things that EQ can't correct, like variability with temperature, age, nonlinear distortion, etc.
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post #27902 of 30660 Old 02-15-2017, 12:33 PM
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Originally Posted by rcohen View Post
No, I'm not aware of any "pure direct" mode.
If you set the PEQ to 0db, it won't modify the numbers (the part that actually matters), but it's still working in the digital domain.

I suspect he meant that the servo inherently corrects certain things that would otherwise need to be corrected with EQ. It also corrects some things that EQ can't correct, like variability with temperature, age, nonlinear distortion, etc.
The direct servo technology is working in the analog domain, from what I understand. What I am able to gather from Rythmik's explanation is that the DSP is for fixing room anomalies:

http://www.rythmikaudio.com/servo_dsp.html

But, it does make sense that maybe it was easier to design the plate so that the D/A conversion is always happening, for simplicity. It might be possible to avoid this, for those interested, using the speaker level inputs rather than the LFE? This would be out for me, since I want to use the LFE output for simplicity.
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post #27903 of 30660 Old 02-15-2017, 12:38 PM
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Originally Posted by Schrodinger23 View Post
The direct servo technology is working in the analog domain, from what I understand. What I am able to gather from Rythmik's explanation is that the DSP is for fixing room anomalies:

http://www.rythmikaudio.com/servo_dsp.html

But, it does make sense that maybe it was easier to design the plate so that the D/A conversion is always happening, for simplicity. It might be possible to avoid this, for those interested, using the speaker level inputs rather than the LFE? This would be out for me, since I want to use the LFE output for simplicity.
Yeah, the servo may be analog, but I believe the EQ/filter portion is digital.
My understanding is that the phase is a digital delay, so I assumed all the DSP is digital.
You are right that LFE bypasses some of the EQ/filter stuff, but not all of it.
I don't know whether the remaining portion is analog.

I do know that you can't hear the difference.
I doubt you can even measure it, aside from the low-pass filter used in the line input.

BTW, there's nothing in that link that suggests that the sub doesn't use any DSP. Virtually all good modern subs use DSP in their amp plates.
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post #27904 of 30660 Old 02-15-2017, 01:07 PM
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Originally Posted by rcohen View Post
I disagree with the quoted concerns about DSP. DSP doesn't replace what a servo does, but Rythmik subs do contain DSP and therefore include a AD/DA conversion. And that's totally fine.
I agree that the Ascend comments regarding DSP should be disregarded. Oversampling is so great in these lower frequencies there should be no detriment, even with multiple A/D & D/A conversions.

Utlizing an additional external DSP/PEQ such as the MiniDSP, Antimode, or even Behringer along with measurement will improve your in-room bass, not degrade it.
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post #27905 of 30660 Old 02-15-2017, 01:12 PM
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SVS does a good job of discussing sealed vs ported WRT phase rotation, group delay & ringing.

https://www.svsound.com/blogs/svs/75...aled-vs-ported
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post #27906 of 30660 Old 02-15-2017, 01:13 PM
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You would expect that Rythmik would implement as much as possible (but no more) in the DSP circuit. Who needs extra components, distortion, or expense without a real benefit?
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post #27907 of 30660 Old 02-15-2017, 01:19 PM
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Originally Posted by Schrodinger23 View Post
I was asking some questions to Brian on the Ascend Acoustics forum and he finally was able to convince me the downsides of a ported design over that of a sealed design.
What's the size of your room. Are you going duals? F25s? F28s!? 👍
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post #27908 of 30660 Old 02-15-2017, 01:57 PM
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What's the size of your room. Are you going duals? F25s? F28s!? 👍
Room will be 12.5 ft x 18.5 ft by 7.2 ft. Was thinking dual F25s, but I'm not sure about pointing one behind an acoustically transparent screen. I know, it sounds like I am have lost my mind going with subs this large in a room this small, but looking at the measurements of the DIY F12:

http://www.hometheatershack.com/foru...ealed-56l.html,

it can only get to about 95 dB before compression begins to set in. Since I am thinking of duals and those freqeucies will be supported by the room we can estimate about a 10 dB gain there. So in my room I might be able to get 105 dB peaks cleanly (without any compression, etc.) with dual F12s. However I might want to crank things up now and then closer to reference volume with is as much as 115 dB peaks. Rythmik states that the F25 is about 8 dB over the F12 at 20 Hz:

http://www.rythmikaudio.com/index.html.

So this means I could hit about 112 dB peaks cleanly. This gets back to the point I was talking about before. To cleanly get close to reference volume in this small of a room with a sealed subwoofer, you need to spend some money. I could go with two FVX15s and be very close to the same output, but at the expense of giving up some transient response in comparison to the sealed sub.
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post #27909 of 30660 Old 02-15-2017, 03:17 PM
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Originally Posted by Norixone View Post
I would not touch the PEQ on the Rythmik if I were you unless you have a specific bump that you measured with a software and adequate mic.
It took me 6 months to dial in my 2 F12s and having Brian and Enrico scratching their heads on why I was not getting the expected performance from my subs. It wasn't until I started actually measuring the room and seeing the effects procured on the sound by moving speakers and subs that I was able to get the integration between mains and subs.
If you use your sub/s to listen to music and films, I would greatly recommend to go down a very unusual path: place a switch between your pre/amplifier and your sub/s and connect the LFE and LINE IN on your sub to the switch. In certain circumstances like mine the settings and eq you can achieve with your preamp do not allow you to get the best of both worlds. So going for a more analogical approach to set the integration between subs and mains will yeld the best effect, while for film and concerts, since there is an LFE channel, you take full advantage of the way the source is encoded.

First thing you'll need to do is to check that your mains are actually in the best possible position and are performing to their max. In my case I had to move them closer to the back wall and closer together to diminish a suckout between 50 and 60 Hz. Trying to compensate the suck out by crossing over the subs at 50 or 60 or even 80 did not help. Moreover, if you do not have the paper cone version of the F12, I can assure you the F12 produces a quite bumped up sound around that frequency, so crossover should not be higher than 60 Hz possibly even lower. The effect of repositioning the speakers was to move the suckout more up in the audio spectrum (between 70 and 80 Hz), but at a lesser degree.
I run my speakers full range, although Yamaha has a starnge way of handling this when adding subs. The setting called extra bass, in presence of a sub, creates a roll off curve at 40 Hz, which happens to be the lower limit at which my ProAc speakers play without loss.

After finally getting a very good imaging and bass from the mains, I placed the subs in the corners behind the mains and pointing allong the walls. Took a measurement from 20 to 500 Hz with my main speakers off.
Then started taking several measurements placing the subs in various positions and angles.
I ended up with both subs out of the corner by 15/20 cm and facing the opposite corners of the room for the smoothest response.
Throught the meaurements I was also able to see that the Yamaha behaved in a very strange way when set to output bass from mains and subs. It cuts off the sub at around 35 Hz. Since the sub curve starts 12 dB higher than the lowest point of my mains (mains show around 70 dB at 40 Hz while sub is at 82 dB at 20 Hz) the crossover between mains and sub happens to coincide at 40 Hz.

I have also found that by setting the crossover on the subs at 80 Hz I could get a little more residual output above the 50 Hz point, which provides an even better integration between mains and subs and as an unespected side effect it ended up to reduce of a couple of dB the suckout on the higher frequency (between 70 and 80 Hz).

Last, but not least, using the LINE IN gives you full control on the phase issue. I used REW's built in frequency output and set it at 40 Hz, which is the crossover point. Both main speakers on and only one sub on. I measured the effect of changing phase on the sub with REW's db metre. Once I obtained the highest output I stopped the phase adjoustment. Then turned on the second sub and did the same.

Of course, before setting the phase, you should adjust the distance of your speakers in your preamp.

Since I have a Yamaha, I have the ability of having to setting patterns so I can have one only for stereo listening and one for the full atmos system. For the second I let Ypao do its thing and just set the switch so that LFE and bass managed sound (60 Hz) is directed to the F12's LFE input.

I was not able to get a good result for stereo listening usinf LFE, EQ, or anything for that matter.

Compared to my previous REL R528 I am getting a lot more articulation, better stereo separation and integration between mains and subs. What I am not getting is the massive bass I was getting with the REL's, which were overriding my mains. It may seem fun to hear Muse FOLLOW ME moving air in the room, but what you were actually missing was all the detail and lower end notes that the REL's could not even approach (roll off started at 25Hz and at 23 Hz they went silent or the passive woofer flapped).

For film I set the F12's at 14Hz extension (same as music) and LOW damping. I set the on/off switch to AUTO so the limiter is engaged and simply enjoy films and music with a whole lot more down there. And when in music mode only, I can assure you I am not able to discern if it is the subs that are giving me the great bass or my mains, which are pretty incredible. And detail, imaging, depth are out of this world as the room just simply shrinks and increases in size following the recording.

It was a very long process and after the first month with the F12s I was ready to sell them, because they were even worse than the RELs. Only thing I was appreciating was the lower end effects in films that were simply not there before (raw of the beast at the biging of Helloboy 2 just an example or its footsteps feeling his presence even before he is revealed ). But was I wrong!!!!!!

Don't give up and try les ortodox approaches, because every situation and need is different
First of all thank you for the incredible detailed information you give on your journey to get the F12s sounding just right. It sounds like you got them dialed in perfectly and are enjoying them very much. Just a couple question for you, first, I noticed you have a Yamaha as well, and mentioned the Extra Bass feature. Do you use this feature? I currently do, and I think it gives the music a little more fullness and more bass of course. I don't know how accurate it is but it sounds good when it's on for most music. What kind of switch device do you use between the preamp/receiver?
I am limited as far as speaker placement and sub woofer placement in my room. I do use my sub for movies and music. I currently have my crossover in my receiver set to 60hz and the main speakers set to small. This seems to give me the best sound. You mention getting a mic and some measurement software to see what's going on. This is probably a good idea, I currently am not well versed with this type of thing or how to start but it seems like it would be beneficial to learn. Thanks again Norixone, very informative! And no, I am not going to touch the PEQ on the back of the Rythmik

Main system | Sony 930D 65 inch | Yamaha RX-A3060 | Ascend Acoustics towers RAAL | Custom Ascend Horizon center | Rythmik F12 | Oppo BDP105 | Lenovo Windows 10 PC with Jriver media server streaming FLAC and WAV files | Surrounds - Def Tech Pro Monitor 1000s

Secondary system : Yamaha RX V2500 | Philharmonic AA bookshelf speakers.
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post #27910 of 30660 Old 02-15-2017, 04:08 PM
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Haha in all honesty though I would love to learn some of this stuff. Any suggestions on where I'd start?
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post #27911 of 30660 Old 02-15-2017, 06:02 PM
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Originally Posted by Marc Alexander View Post
Where is your crossover set and would you mind sharing your waterfall?
80hz

this waterfall was with all 3 subs with 1 ea on 3 different wall sides....last couple days just using the one rhythmik...

the pink waterfall was when dealer set up my stuff with 2 velodyne subs...I obviously cranked up the bass when I bought the rythmik because I like it more bassy, even with ringing.
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post #27912 of 30660 Old 02-15-2017, 06:38 PM
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@torii that's pretty nice. Multiple subs goes a long way to eliminate localization.

I'm working to get some GIK bass trapping now because my room is much liver than yours.
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post #27913 of 30660 Old 02-15-2017, 07:41 PM
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F25 will stay but there will be an F28 with the same cabinet size! End of 2016 so there's been a bit of a delay. They are not taking preorders yet to my knowledge. We are all waiting for an update.
Ok. Has pricing been announced on the new subs?
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post #27914 of 30660 Old 02-15-2017, 07:51 PM
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Rythmik's (Brian's) servo design is analog-based. You can read his patent. The article referenced on the website points out that direct servo control (as implemented in Rythmik subwoofers) is complementary to DSP used for room correction and so forth. Two different things that together create a greater whole than the sum of the parts.
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"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
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post #27915 of 30660 Old 02-15-2017, 07:59 PM
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Rythmik's (Brian's) servo design is analog-based.
Yes, but that doesn't mean there is no DSP employed. While an analog crossover can be implemented, I'm not sure about PEQ, and pretty sure that delay/phase is done digitally.

Yes, Servo is complimentary to Room EQ DSP, but that is just one type of DSP.
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post #27916 of 30660 Old 02-15-2017, 08:05 PM
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I thought Brian told me many years ago it was analog but I'll wait for he or Enrico to respond so we'll all get it right. My servo sub, decades earlier, used a very similar servo circuit and implemented filtering and phase adjustment in the analog domain.

I am fairly familiar with various things DSP can do. When I first became involved with it, bearing in mind I am an analog guy, it was in radar processors, then later SATCOM, EW, ELINT, and all that jazz. I had a lot of theory as well as practice, but those grad classes were a while back, and my advisor has moved on to bigger things...

Cue Brian...
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post #27917 of 30660 Old 02-15-2017, 09:25 PM
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Ok. Has pricing been announced on the new subs?
Not AFAIK
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post #27918 of 30660 Old 02-15-2017, 10:12 PM
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Originally Posted by Darian97 View Post
Ok. Has pricing been announced on the new subs?
From their Facebook page,



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Receiver - Sony STR-DH550
Fronts - Klipsch Reference Premiere RP-280F
Center
- Klipsch Reference Premiere RP-450C
Surrounds - Trash
Sub - Rythmik FV15HP
The Ultimate List of BASS in Movies w/ Frequency Charts Heavy Cinematic | Heavy Electronic|
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post #27919 of 30660 Old 02-16-2017, 07:36 AM
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^^ Congrats! reduce the volume on your current FV by one click or two to compensate for a 6db gain adding another. Match the gain volume knob from the new FV to your current one and run Audyssey cal. You want your sub trims to be around -6 to -11 after calibrating.
Thanks! Second sub arrived yesterday and is in place. Setup went smoothly. Audyssey definitely had me dialing back the volume on each sub. I got them both to the point where Audyssey set them each at -8. My single sub had been set at -9 prior. I had to dial it back 3-4 clicks on the volume with the addition of the second sub.

This has me wondering, and mind you I'm a newb to all this...If a second sub adds 3, 6 db (whatever the db increase is may be for the room) is Audyssey taking that all away? It's clear Audyssey was picking up on a gain with the second sub, but it then resulted in me having to dial back the gain on the subs. So am I going to feel any more output in that scenario or is it just going to be better overall in terms of smoothing the room, hitting all the listening spots, etc. Can I run them both hotter?
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post #27920 of 30660 Old 02-16-2017, 08:23 AM
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Thanks! Second sub arrived yesterday and is in place. Setup went smoothly. Audyssey definitely had me dialing back the volume on each sub. I got them both to the point where Audyssey set them each at -8. My single sub had been set at -9 prior. I had to dial it back 3-4 clicks on the volume with the addition of the second sub.

This has me wondering, and mind you I'm a newb to all this...If a second sub adds 3, 6 db (whatever the db increase is may be for the room) is Audyssey taking that all away? It's clear Audyssey was picking up on a gain with the second sub, but it then resulted in me having to dial back the gain on the subs. So am I going to feel any more output in that scenario or is it just going to be better overall in terms of smoothing the room, hitting all the listening spots, etc. Can I run them both hotter?
Audyssey's automatic levels set the subs for a flat response, which will cancel out the loudness gain. You can increase the levels on your receiver or subs after calibration if you prefer more bass. I think more people do that than not.

One thing to watch out for when turning up sub gain like that is that if you use inconsistent bass mgmt crossover points for different speakers, that will cause you to have inconsistent frequency response between those speakers.

In order to avoid that, you either need consistent crossover points, pre-bass mgmt EQ, or counteracting post-bass mgmt EQ. Or, failing that, you can live with inconsistent frequency response. (Not everyone cares.)
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^^ what you gain is more headroom. Audyssey will set all of your sub(s) to 75db regardless of you have 1 sub or 10 subs. Of course, you can run your subs hotter, much hotter than before. Is your volume knob on each sub at the same spot/position?
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^^ what you gain is more headroom. Audyssey will set all of your sub(s) to 75db regardless of you have 1 sub or 10 subs. Of course, you can run your subs hotter, much hotter than before. Is your volume knob on each sub at the same spot/position?
The volume knob is at the same on each, just a little below half. If not the same, they would be within a click of each other.

I didn't get to test much last night, but I did quickly play the opening to Edge of Tomorrow and the club scene from John Wick. I wish I would have played them more recently, before the switch, for better comparison. I do recall being a bit nervous during Edge of Tomorrow as the single sub was really working, even chuffing some. The 2 seemed to have no issue at all. During John Wick, I want to say it was more tactile. Every gun shot you could feel.

Having 2, how hot is safe to run them?
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post #27923 of 30660 Old 02-16-2017, 09:18 AM
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Originally Posted by Marc Alexander View Post
I agree that the Ascend comments regarding DSP should be disregarded. Oversampling is so great in these lower frequencies there should be no detriment, even with multiple A/D & D/A conversions.

Utlizing an additional external DSP/PEQ such as the MiniDSP, Antimode, or even Behringer along with measurement will improve your in-room bass, not degrade it.

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Originally Posted by DonH50 View Post
I thought Brian told me many years ago it was analog but I'll wait for he or Enrico to respond so we'll all get it right. My servo sub, decades earlier, used a very similar servo circuit and implemented filtering and phase adjustment in the analog domain.

I am fairly familiar with various things DSP can do. When I first became involved with it, bearing in mind I am an analog guy, it was in radar processors, then later SATCOM, EW, ELINT, and all that jazz. I had a lot of theory as well as practice, but those grad classes were a while back, and my advisor has moved on to bigger things...

Cue Brian...

The good news is that if DonH is right and the servo circuit with the filtering and phase adjustment is done in the analog domain, then we can still have the best of both worlds. On the Rythmik page Brian talks about servo and DSP being complementary approaches to different problems (though DSP can address some of what the servo does on a sub). If one has a Denon or Marantz receiver/processor with Audyssey, for example, and the source is a digital source (which is what most sources will be these days outside of those that listen to vinyl), then what comes into the receiver/processor is a digital signal. And Audyssey can help correct anomalies from the room that are left over after one tries to address them with room treatments, using multiple subwoofers, gettting the seats located optimally in the space and of course proper speaker placement. Afterwards, the digital to analog conversion takes place and maybe the Rythmik just handles the analog signal without doing another A/D and then D/A conversion. Again, even if Rythmik is doing the extra conversions, then it might not even be audible, but it would give me peace of mind that at least mathematically nothing is lost and what is getting to the subwoofer is as unaltered as possible (except for fixing the problems caused by the room while the signal was in the digital domain).
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post #27924 of 30660 Old 02-16-2017, 10:04 AM
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Having 2, how hot is safe to run them?
How big is your room? Is it sealed or opened to other area of the house?
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post #27925 of 30660 Old 02-16-2017, 10:07 AM
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Originally Posted by Schrodinger23 View Post
Room will be 12.5 ft x 18.5 ft by 7.2 ft. Was thinking dual F25s, but I'm not sure about pointing one behind an acoustically transparent screen. I know, it sounds like I am have lost my mind going with subs this large in a room this small
I like the choice of dual F25s. You're headroom analysis is spot on. You can always lay the F25 horizontally under your center channel speaker behind the screen.

I know you seem to be getting stuck on DSP and A/D D/A conversions but with ample headroom you can utilize a MiniDSP or other customizable RoomEQ to dial in your own house curves (one for movies and another for music for example).
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post #27926 of 30660 Old 02-16-2017, 10:25 AM
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Originally Posted by tvuong View Post
How big is your room? Is it sealed or opened to other area of the house?
So this is in my finished basement. There is the stairway and a 13x5 hallway leading to the room. The room is roughly 16x18. Subs and front speakers are along the front wall, 16' wide. Couch is on opposite end. Seating distance is probably 14'. Behind the couch is a large, 10' opening to the other room down there. All said, it's roughly 600 sf of connected space, with 8' ceilings. Quick diagram attached for reference.
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post #27927 of 30660 Old 02-16-2017, 11:15 AM
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Originally Posted by Marc Alexander View Post
I like the choice of dual F25s. You're headroom analysis is spot on. You can always lay the F25 horizontally under your center channel speaker behind the screen.
Good to hear that the headroom will likely work out to be what I expect. Thanks. When I tell folks on other boards the subs that I have planned for this small room, they think that I have lost my mind. I was thinking about laying it horizontally exactly as you describe or just turning it sideways so that the driver is not firing directly into the acoustically transparent screen.

Do you think that I will get any screen movement on my screen if I have a bass heavy movie cranked up?

I will have the acoustically transparent screen mounted to a false wall. But seeing any movement on the screen would be a deal-breaker for me. This is why I think I might have to go with four F15HPs and just place them in the four corners. I really don't like the idea of spending the extra money to do this and I get slightly worse standard deviation and Max minus Average from seat to seat according to Harmon's research. But, if I don't get the screen movement, it is worth the extra expense.


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Originally Posted by Marc Alexander View Post
I know you seem to be getting stuck on DSP and A/D D/A conversions but with ample headroom you can utilize a MiniDSP or other customizable RoomEQ to dial in your own house curves (one for movies and another for music for example).
With Audyssey, if you get a newer receiver you can get an app for $20 to $25 to dial in your own house curve. This is possible without the extra A/D and D/A conversion. I would love to have two or three EQ settings, for the whole frequency range though, that are available with the push of a button. Not because of music vs. movies, but because I am planning for two rows of seats. It would be awesome to have one EQ setting for Row 1, if that is all that I plan to use. Another if I only plan to use Row 2. Yet another If I plan to use both, shooting for a balanced EQ that is pretty good for each row, but likely not optimal for each one separately as in the other two EQ settings. This isn't something that is difficult to implement since storage space is so cheap, but as far as I can tell the only reasonably approached receiver/processor that can do this is Anthem (and they are pushing what I would call reasonably priced ). Audyssey should really try to implement this feature in their new app. Heck I can get two or three Denon's or Marantz's with MultEQ XT 32 for the price that the Anthem receiver/processors with this feature start at. Just have a different receiver for each EQ configuration and set up different buttons and macros in a Harmony remote for Row 1, Row 2, or Row 1 + Row 2 Eqs. But, this might be more complex than I want to get into. I guess I might be going overboard with what I want my EQ to be as well.
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post #27928 of 30660 Old 02-16-2017, 11:25 AM
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I have four F12's in a sealed room about the size of yours (mine is ~13'3" W x 17'7" L x 8'6" H) and they are more than enough. I didn't have room for 15" subs in front with the console and my (wide planar) speakers but cannot imagine what four 15" subs would do in that room... Significant damage, I am sure.

There are a number of tests showing multiple A/D - D/A conversions are inaudible but YMMV. Note there is always an ADC in the path for analog inputs if Audyssey is used (and often if not), and of course at least one DAC.

I don't have a screen but have seen a few and IME putting a sub behind one has always caused problems, typically a bit of video distortion or moire patterns. When I was looking for one a couple of the companies said regular speakers were OK but they did not recommend subs even behind an "acoustically transparent" screen. That was a few years ago so maybe they've improved, I don't know, but I'd be leery.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley

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post #27929 of 30660 Old 02-16-2017, 11:58 AM
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You'll be able to hit reference very cleanly. This is what I've been able to achieve with one calibrated at my MLP about 14' you'll probably have similar room gain.
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post #27930 of 30660 Old 02-16-2017, 12:12 PM
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Quote:
Originally Posted by Marc Alexander View Post
I like the choice of dual F25s. You're headroom analysis is spot on. You can always lay the F25 horizontally under your center channel speaker behind the screen.

I know you seem to be getting stuck on DSP and A/D D/A conversions but with ample headroom you can utilize a MiniDSP or other customizable RoomEQ to dial in your own house curves (one for movies and another for music for example).
Hi Marc,

Using your post to comment on this issue.

I checked out some older DSP chips, circa 2002... These chips operate at frequencies in the 100MHz to 150 MHz range. In comparison bass frequencies change at glacial speeds. My old brain can't figure out how something so slow, 10-150Hz, ie 110 msec-7 msec could be harmed by processing taking place in the 8 nanosecond range. Of course that is for 1 clock cycle, a 1,000 operations would be in the 8 usec range, roughly 1,000 times faster than the 150 HZ signal is changing. I just don't see how any artifacts generated in this range could possible effect a massive bass driver which can't move anywhere near that speed. Even a 20KHz signal takes 50 usec to complete 1 cycle. I will admit my math may be off a bit

Maybe Brian will enlighten me

Regards, Ken (Retired)
9.1) Denon 4520CI; Samsung 55H8000 & BD-F7500; R&LRS/L/R SVS Ultra BS,
Ultra Center; FH & SS Polk; Rythmik F12; CyberPower CP1500PFCLCD (x2)
2.1 Ch.) Nakamichi RE-2, CDC-4A, CR7A, Denon 300F/Ortofon 2M Bronze;
ADS L1290(x2); PINNACLE BABYBOOMER SUB, PANAMAX MR4300
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