Either by placing a measurement mic near the port (distance less than half the port diameter), or doing an impedance sweep of the driver inside the cabinet. Based on the 18Hz cutoff specified by Klipsch, I would suspect a port tune around 23Hz, as the response starts to rolloff around that point.
-
Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Subwoofer Comparison
- Thread starter sweetchaos
- Start date
Either by placing a measurement mic near the port (distance less than half the port diameter), or doing an impedance sweep of the driver inside the cabinet. Based on the 18Hz cutoff specified by Klipsch, I would suspect a port tune around 23Hz, as the response starts to rolloff around that point.
Andysu
Major Contributor
- Joined
- Dec 7, 2019
- Messages
- 4,101
- Likes
- 2,283
so i guess playing Star Trek IV at THX TAP levels. how about sperm, sperm whales sub sperm deep depth humping humpbacks.
there is a no, no about eq boosting low frequencies on subs in cinema manuals and sooner or later they'll blow their subs and home theatre systems up. sooner or later.Never been one to throw random EQ adjustments at anything. I play back the source with no changes. Furthest I ever went was to remux the DVD audio track for Master & Commander together with the bluray... Those guys are seriously throwing 20dB of LF boost on children's movies? Altering reference quality movies like Dune?
Even then, everything is rolled off below 15hz.
i don't need any boost on say 'Star Trek II', that reaches down to surprisingly 15Hz on baby boom track on DVD. don't need no 4k i cat litter-d that 4k disc. 'superman II' reaches down low forget which not played DVD in few years, baby boom with megasound.
decouple it and enjoy that sub they way you want to all the time! simple HVAC ant-vibration pads work well. the SVS isolation feet kit works well too but might require some basic modification for certain brands.
i decoupled my subs to tame some internal vibrations i would get on my plantation blinds proximate to the subs. it worked a treat. the additional benefit was my neighbor though i had got rid of my subs. may need to add more subs!
I'm still a bit confused about the exact math I would need to run to understand the max SPL in my room (which is just around 5000 cubic feet, so it's on the border between large and extreme). How are boundaries taken into account? If corners gives such a nice SPL boost, would they still have some kind of disadvantage, say more distortion or less flat response? In my room the corner actually gave the flattest response (not flat, but other locations were worse) along with significantly higher SPL (at least according to Audyssey calibration trims chosen for each location). What about multiple subs? For example, would a pair of Pb-2000 (or at least a pair of Pb-2000 Pro) classify as extreme together?
Would all "extreme" level subwoofers let me play reference levels in the bass in worst-case scenario? Or is it calculated based on a more realistic scenario? Not that I need reference levels, but I do listen at -18db and use DEQ so lowest frequencies are more like -9db from reference, and might need some more headroom for maybe listening a bit louder or boosting the bass a bit to taste or just for Audyssey headroom. I want to know if the data here is enough to figure out whether my system can obtain said levels, and if not, what system could, as well as what levels I can safely play with what I have or if I spend X money.
Would there still be some difference in sound quality other than just the measured SPL? Would it be significant? As in, would a subwoofer with max 110db play 100db "cleaner" than a subwoofer that maxes out at 100db?
Also I guess I also need to figure out how much SPL my speakers can handle. Is there a simple way to measure that in REW?
From here I understand that measuring subwoofer distortion at high SPL with umik won't work, but maybe there is an alternative trick to find the "local/personal" limit by measurement/experiment?
Would all "extreme" level subwoofers let me play reference levels in the bass in worst-case scenario? Or is it calculated based on a more realistic scenario? Not that I need reference levels, but I do listen at -18db and use DEQ so lowest frequencies are more like -9db from reference, and might need some more headroom for maybe listening a bit louder or boosting the bass a bit to taste or just for Audyssey headroom. I want to know if the data here is enough to figure out whether my system can obtain said levels, and if not, what system could, as well as what levels I can safely play with what I have or if I spend X money.
Would there still be some difference in sound quality other than just the measured SPL? Would it be significant? As in, would a subwoofer with max 110db play 100db "cleaner" than a subwoofer that maxes out at 100db?
Also I guess I also need to figure out how much SPL my speakers can handle. Is there a simple way to measure that in REW?
From here I understand that measuring subwoofer distortion at high SPL with umik won't work, but maybe there is an alternative trick to find the "local/personal" limit by measurement/experiment?
a pair of PB-2000's would be considered extreme if you stacked them. i.e. literally one on top of the other. stacking them would give you +6 dB across the frequency range.
a single pb-3000 would be cheaper than 2x pb-2000 pro but a single monoprice monolith thx 13 will give you svs pb-4000 level performance at pb-3000 price. you would want something along those lines for a 5,000 ft3 room. a pair would be great.
Shouldn't we still get average +3db with a non-stacked pair though?
And my question still stands about how to figure out how much I'm actually missing (meaning what max level can I play), as I won't actually play full reference level, and also probably won't spend so much.
I also need to figure out the maximum of the speakers/receiver, as no point having subwoofers at reference if speakers are maxed out at a lower level.
Basically I want to be able to better understand my current limits, then see if I can get any significant improvement for a price I'm willing to pay.
Also, it doesn't seem like any of the brands that can give SVS a fight in VFM are available locally in Israel, and ordering something like that online is pretty complicated and usually not worthwhile.
And my question still stands about how to figure out how much I'm actually missing (meaning what max level can I play), as I won't actually play full reference level, and also probably won't spend so much.
I also need to figure out the maximum of the speakers/receiver, as no point having subwoofers at reference if speakers are maxed out at a lower level.
Basically I want to be able to better understand my current limits, then see if I can get any significant improvement for a price I'm willing to pay.
Also, it doesn't seem like any of the brands that can give SVS a fight in VFM are available locally in Israel, and ordering something like that online is pretty complicated and usually not worthwhile.
Last edited:
yes you will get a boost from a second sub but your question was if it would go from a large to an extreme rating. realistically to achieve that you would need to stack them.
how much amp power you need as a minimum will come down to your listening distance from the speakers and the real world sensitivity of those speakers. with such a large room it's not unreasonable based on the speakers you choose, and your distance from them, that the sound pressure level at your MLP could be as low as 80 dB at 1 watt - this is worst case scenario assuming as much as a 16 ft / 5m distance from the speakers and those speakers being below average sensitivity. 86 dB at the MLP would be more typical for smaller spaces. even if you only ever listen at moderate levels you will still want to be able to achieve at least 96 dB at your seated position / MLP.
back to your original question of potential room gain. this could be relatively straight forward or quite difficult to figure out. simple fast rule is that you have a large space so there will be very little. a small room with a longest wall length of 14 ft / 4.25m should see a 12 dB/octave boost beginning at about 40 hz for a sealed sub (i.e. +12 dB at 20 hz). the gain is less for ported subs because they are rolling off naturally at 24 dB/octave and will likely be implementing a steeper subsonic filter to protect the driver from over excursion. if your longest room dimension is say 25 ft / 7.6 m then room gain won't begin until 22.5 hz. just to further confuse all of this you could experience room modes that can excite or cut certain frequencies along the path and are the primary reason why you should be very selective about subwoofer location when a single sub is used.
how much amp power you need as a minimum will come down to your listening distance from the speakers and the real world sensitivity of those speakers. with such a large room it's not unreasonable based on the speakers you choose, and your distance from them, that the sound pressure level at your MLP could be as low as 80 dB at 1 watt - this is worst case scenario assuming as much as a 16 ft / 5m distance from the speakers and those speakers being below average sensitivity. 86 dB at the MLP would be more typical for smaller spaces. even if you only ever listen at moderate levels you will still want to be able to achieve at least 96 dB at your seated position / MLP.
back to your original question of potential room gain. this could be relatively straight forward or quite difficult to figure out. simple fast rule is that you have a large space so there will be very little. a small room with a longest wall length of 14 ft / 4.25m should see a 12 dB/octave boost beginning at about 40 hz for a sealed sub (i.e. +12 dB at 20 hz). the gain is less for ported subs because they are rolling off naturally at 24 dB/octave and will likely be implementing a steeper subsonic filter to protect the driver from over excursion. if your longest room dimension is say 25 ft / 7.6 m then room gain won't begin until 22.5 hz. just to further confuse all of this you could experience room modes that can excite or cut certain frequencies along the path and are the primary reason why you should be very selective about subwoofer location when a single sub is used.
To find out what you are missing I'd recommend using REW to take some in room measurements and see what the response is at the listening position. The primary improvement you could make with multiple subs is placing them and EQ ing them in a way to minimize nulls and smooth out your overall frequency response, third is better low end extension. You will get some overall SPL gain but I think that is secondary to getting a smooth frequency response and better low end extension.
It's an open space with kitchen etc, so while large, the listening distance is actually 2.3m from the mains, 3.4 from the surrounds, and about 3m from the subwoofer.
Even if I don't change anything because other things are more important, I still want to understand how to measure the maximum of my system so I don't cross it. It's not clear to me if there is a way to get that kind of information from REW measurements (like find the SPL where distortion increases? Is that a practical approach?).
Subwoofer frequency response shows noticeable higher energy at the lower frequencies, and while it could be modes, I doubt that is the case for all frequencies past the ~50Hz peak, especially that I couldn't detect any obvious modes at most of those frequencies when playing a test tone. Same goes for the 30-40Hz range which doesn't seem to be boosted by modes. The 20Hz and 26Hz are modes to the width (20Hz, and actually 45Hz dip seems to be the 2nd harmonic even though it isn't exactly double the frequency) and length (26Hz) of the room. Room is about 6.5x8.5x2.57m (only ceiling measurement is accurate, and only 2 walls are 100% straight so it's not really a perfect rectangle).
Actually both 24Hz dip and 26Hz peak seem to be the 1st length mode, except at 24Hz the null is wide enough to affect the listening position (which is a bit away from the center of the null), while at 26Hz the null is narrow and the listening position is already getting loud (not as loud as the 2 walls, but louder than other frequencies).
Basically seems like before anything I should probably get a better receiver with XT32 or better. And probably convince the wife to get some minimal acoustic treatments stylish enough to fit in the living room. But I wonder if there are any other good value for money upgrades that will actually help (which requires understanding the limits of the current system, so that I can prioritize...).
Rhythmik F12, SVS SB-3000, Arendal 1961 1S are all within about $100 of your budget. The Arendal being the lowest priced. Assuming your room size is in feet you should see a room gain bump starting at ~28 hz for an approximate 12 dB increase at 14 hz - in a perfect world that is.
sealed subs are an easy DIY project if you feel up to it too.
The monolith subwoofers are on sale now, including the new versions (V2).
Search -MONOLITH SUBWOOFERS - HDMI Cable, Home Theater Accessories, HDMI Products, Cables, Adapters, Video/Audio Switch, Networking, USB, Firewire, Printer Toner, and more!
Monoprice, Inc. (DBA. MonoPrice.com) specializes in the wholesale distribution of world class cable assemblies for home theater, PC, and high technology industries. MonoPrice.com offers a wide range of products from standard PC products, network cables, and HDMI cables to custom cable assemblies...
www.monoprice.com
These got a positive review by erin in 2020. Are they still such a good value or are there better options at this price point nowadays? (Thinking on the 10" at 500eur myself...)
Monoprice Monolith 10, 12 and 15-inch Subwoofer Review
Info: I just wrapped up my review of the following Monoprice Monolith 10/12/15-inch subwoofers: Monolith by Monoprice 10in THX Select Certified 500-Watt Powered Subwoofer - $499 Monolith by Monoprice 12in THX Ultra Certified 500-Watt Powered Subwoofer - $799 Monolith by Monoprice 15in THX Ultra...
audiosciencereview.com
Erin reviewed version 1 of these subwoofers.These got a positive review by erin in 2020. Are they still such a good value or are there better options at this price point nowadays? (Thinking on the 10" at 500eur myself...)
Monoprice Monolith 10, 12 and 15-inch Subwoofer Review
Info: I just wrapped up my review of the following Monoprice Monolith 10/12/15-inch subwoofers: Monolith by Monoprice 10in THX Select Certified 500-Watt Powered Subwoofer - $499 Monolith by Monoprice 12in THX Ultra Certified 500-Watt Powered Subwoofer - $799 Monolith by Monoprice 15in THX Ultra...
In my opinion monolith offers great value for their subwoofers (i.e., they will be some of the lower cost models in each audioholics rating category for subwoofers). Another other value offering is HSU, but I don't know their availability outside the US.
The five-year warranty is also good among subwoofer companies, but not quite as good as SVS.
Thanks! May i ask what is the difference between the two versions? If i compare pictures of the back they seem identical (erins review vs current monoprice website). PS: sorry but i know nothing about subs.
The designer commented a while back that they are improved in terms of output I believe, but they left the specs the same. Not sure if that was due to the speaker driver or the amp etc. They also come in gloss as an option now. I see no reason to believe that they are not better, but I imagine the benefits are small between the two and that it would be better bang for the buck to buy v1.
That is an interesting question! The performance of each model is nearly identical (within 1db approximately). Maybe we should ask @MonolithGuy for the differences between V1 and V2 subwoofers.
In our last conversation others were speculating about various internal improvements.
i have read elsewhere that they slightly refined the driver on the v2 models but relatively speaking it's the visual appearance of the cabinet that received marked improvement. blasphemy on ASR, i know!
With the V2 10" and 12" THX, there is a small increase in magnet mass but otherwise same driver, and 0.7 to 1dB more output.
I believe the amp is the same as V1 but not 100% certain
Last edited:
Similar threads
