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Got a subwoofer, but I'm not so sure I need it. Help :)

sarumbear

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Peluvius

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Subwoofers aren't "easy" to setup and integrate, generally speaking. They can be a complete PIA. Quite a few here just don't use them because they have not experienced them adding anything to their own setups so you would certainly not be alone if you had no need for a sub in your situation. I have personally found they add a visceral punch that I could never get just with the full range speakers I have tried. Have you tried the "crawl" test to see where your optimal placement is? It isn't always on the floor .... o_O
 

sigbergaudio

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Subwoofers in a system without support for highpassing the mains is ..problematic to the point that I'm not sure I would recommend it at all. You will only be able to utilize a fraction of the potential of the subwoofer since it needs to be crossed over very low, you don't get any reduction in distortion in the bass range since the speakers are still doing their best to reproduce low bass, and you get no additional headroom for the same reason. Some kind of DSP/EQ (either built into the sub or external) is also almost a must to get linear bass reproduction.

Once you hear a well integrated sub in a stereo system, I doubt you will go back. But the road to get there is not without obstacles.
 

ZolaIII

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Subwoofers in a system without support for highpassing the mains is ..problematic to the point that I'm not sure I would recommend it at all. You will only be able to utilize a fraction of the potential of the subwoofer since it needs to be crossed over very low, you don't get any reduction in distortion in the bass range since the speakers are still doing their best to reproduce low bass, and you get no additional headroom for the same reason. Some kind of DSP/EQ (either built into the sub or external) is also almost a must to get linear bass reproduction.

Once you hear a well integrated sub in a stereo system, I doubt you will go back. But the road to get there is not without obstacles.
Arguably you would use subwoofer to cross good 7" bookshelf speakers at 80~100 Hz or higher if they are closed enclosure and even more up if they are smaller. Devil always lies in details.
Those 3 way speakers have paper (compression) midrange driver's and impregnated ported fiberglass woffer's (2x per speaker) which all are 7" that are crossed at 350 Hz. So they don't really need subwoofer for music reproduction at least.
 

sigbergaudio

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Arguably you would use subwoofer to cross good 7" bookshelf speakers at 80~100 Hz or higher if they are closed enclosure and even more up if they are smaller. Devil always lies in details.
Those 3 way speakers have paper (compression) midrange driver's and impregnated ported fiberglass woffer's (2x per speaker) which all are 7" that are crossed at 350 Hz. So they don't really need subwoofer for music reproduction at least.

Not sure if I understand your point here, but if it is that only bookshelf speakers need subwoofers, I disagree. :)
 

ZolaIII

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Not sure if I understand your point here, but if it is that only bookshelf speakers need subwoofers, I disagree. :)
Hardy that I can help you with that, after all you are manufacturer.
Crossover between those 7 inchers is fairly low (350 Hz) and there are two of those fiberglass one's per each speaker in ported enclosure pushing only bass range which again is enough for 30 Hz - 6 dB and 40 Hz 0 dB (or even more when low bass is mixed together on both chenels which again is usual). That is enough for even electronic bass in genres favoring it and even such are cut off below 30 Hz in mastering process.
 

Eetu

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Have to agree with some other comments, you are probably better off not using the sub unless you get some sort of bass management (MiniDSP/AVR..) and perhaps add a second sub. I run dual subs, not primarily for the extension or SPL but for the smoother in-room response and because they allow my high-passed main speakers play everything above 100Hz more effortlessly.
 

audiofooled

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A lot of good advice here. Yes, you need bass management or at least dedicated LFE channel to connect your sub and high pass the mains for proper integration. And that's only a fraction of the business because you still need to place it and set it up optimally for best results.

To me It's no surprise that what you measured and subjectively experienced, is the way it is. You are using only a fraction of it's true potential and this is what you hear.
How do you feed the signal to your sub? Do you use some kind of Y adaptor from your amp's pre out?

Anyway, what you may try is placing the sub right in the middle between your speakers and as close to in line with them. If needed, pull your main speakers into the room to make it happen. No matter if it can't stay that way, this is just to give you a hint of what is possible. Attenuate the bass on your amp to your mains about -1,5 to 2 db. This is not the same as having them high passed, but it may help.

Now, because the sub is roughly in line with your mains, set the phase to it to 0 degrees. Set the crossover to max (150 Hz i believe). Crank the sub up to roughly the same as the amp. From here you may fiddle with the settings of crossover, volume, phase, bass on your amp, etc. The goal here is to let the sub handle about half of the bass duties and let it play at least to 80 Hz in order to let it show it's potential. When you're done, the sub must have sonically "disappeared" but felt with power and authority. At the same time, your mains should play effortlessly because huge part of their bass duties are handled by the sub.

I'm not saying this would be easy, in the end you must fine tune it by ear, but once you get there, you're in heaven. Then you measure and see if matches what you hear and feel.

I hope you find this worth a try and I hope you feel the real impact ;)
 

ZolaIII

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Most people here would feel impact in their ass but not in their head.
Cuple of question for such.
What do you get when you cross two way speaker with the sub? Is it a three way?
Would two 7" drivers roughly behave same as one 10" one regarding their bottom end response (in same type of enclosure of course)? Similarly four of those would produce similar results as two of 10" one's in separate enclosures including regarding of better filling holes?
And there you have manufacturers 10" two woffer's in same enclosure sub costing 3K $ no sweat capabilities incorporate in speakers alone.
Future more; do you really need mind blowing SPL capabilities in very low end? No you don't in 99.9% of use cases and you can't get them in case of large halls without serious long trow tweaks with large cascade of sub's and even so range will be rather limited (simple physics). Is it ridiculous to insist on more than 30 Hz 0 dB for pretty much anything ever mastered even remotely properly to hear artificial chuff which is not in a recording?
 
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Cote Dazur

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does my system really needs a sub?
That is a question you have to ask to yourself, why did you buy the sub in the first place?
Doesn’t seem, from what you wrote, that you feel you are missing bass.
What did you expect the subwoofer would do?
Most add a sub (or more) because their speakers, either by design or placement, cannot produce the bass they would like to hear in their room/set up, or because they want the bass to be present at more than one spot.
 

Willem

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This once again points to the neeed for a good highpass filter in stereo systems. Sadly, most amps and preamps do not offer this, and the miniDSP 2x4HD only offers four channels, (i.e. in this case only two for subs), and measures not that well and much worse that good modern DACs and amplifiers. I now use three subs, so I have adressed this with a passive high pass filter in the cable from the RME ADI-2 to the power amp, and use the 2x4HD only to filter the subs.
 

audiofooled

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Most people here would feel impact in their ass but not in their head.
Cuple of question for such.
What do you get when you cross two way speaker with the sub? Is it a three way?
Would two 7" drivers roughly behave same as one 10" one regarding their bottom end response (in same type of enclosure of course)? Similarly four of those would produce similar results as two of 10" one's in separate enclosures including regarding of better filling holes?
And there you have manufacturers 10" two woffer's in same enclosure sub costing 3K $ no sweat capabilities incorporate in speakers alone.
Future more; do you really need mind blowing SPL capabilities in very low end? No you don't in 99% of use cases and you can't get them in case of large halls without serious long trow tweaks with large cascade of sub's and even so range will be rather limited (simple physics). Is it ridiculous to insist on more than 30 Hz 0 dB for pretty much anything ever mastered even remotely properly to hear artificial chuff which is not in a recording?

No.
 

Marc v E

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This once again points to the neeed for a good highpass filter in stereo systems. Sadly, most amps and preamps do not offer this, and the miniDSP 2x4HD only offers four channels, (i.e. in this case only two for subs), and measures not that well and much worse that good modern DACs and amplifiers. I now use three subs, so I have adressed this with a passive high pass filter in the cable from the RME ADI-2 to the power amp, and use the 2x4HD only to filter the subs.
Mostly agree. Especially on amps missing high pass and low pass filters.


I'm under the impression that the latest offerings from minidsp offer quite decent performance, around -103db sinad with eq filters applied. What's your experience so far?
 

sigbergaudio

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Yes!
2x10" 40 Hz @ 100 dB SPL=3.4526
VS 4x7" the same =3.5231 Xmax.

You can't just compare the size of the drivers. Do you think these drivers have the same capacity? Both are 10"

294-110_HR_0.default.jpg

292-410_HR_0.default.jpg
 

sigbergaudio

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Quoted comment removed by Moderator
I have no idea what you are talking about, and I strongly suspect you don't either. And I would appreciate if you would refrain from name calling.
 
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sigbergaudio

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Quoted Comment removed by Moderation.

I'm not really trying to be a clown. If I have offended you somehow I apologize. On your end you have both called me a retard, and you are also talking down our products which it seems you find overpriced (I would be interested to see how you calculate that). I have not mentioned them in this thread, and neither have anyone else, so not sure why you are bringing them up.

If you see products out of your price range, the best approach is probably to just not buy them, and then move along. No need for name calling.
 
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Digital_Thor

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Try this....
Let your mains play full spectrum, their natural roll off will blend easier than most filters - it's a phase issue. Now use your pre-outs to your sub - best would be minimum 2. Then only adjust subs with gain/phase and cut off frequency, until you measure minimum suck outs at the listening position - with both mains and sub/subs playing, because it's the combined sum of everything that truly matters. Overlap between subs and mains, reduce suck outs and even out the overall response most effectively.

Caveat is, that you need EQ to remove the last bumps, when you reached a response with minimum suck outs = as few destructive interferences as possible.

Almost any simple DSP between pre-out and sub/subs works - to remove those remaining bumps + room gain/ room resonance.
 

Ricardojoa

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Your front dig low enough to omit the use of a sub. In the past I always believe in sub but ever since i have gotten the bmr i feel like i can live without one for sure for music.
 
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