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Subwoofer suggestions

mj30250

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Your best option would be another Rythmik F12.

Better yet if you have the budget and time to wait would be a pair of these -https://www.harbottleaudio.com/cassini-tradition/112t
or https://www.harbottleaudio.com/cassini-tradition/115t. Of Funk audio which work with Harbottle.

As for PSA- not a fan. Really gives me DIY built in a garage vibes.

The owner/lead designer of PSA co-founded SVS (he's the "V"), so it's not exactly some two-bit musty garage operation. If you're simply referring to aesthetics, then yes, the standard cabinets are pretty basic function-over-form offerings and won't win any design awards. However, they've done many higher-end custom finishes per request. Of course, that comes at a cost.
 

Battlebeast

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The owner/lead designer of PSA co-founded SVS (he's the "V"), so it's not exactly some two-bit musty garage operation. If you're simply referring to aesthetics, then yes, the standard cabinets are pretty basic function-over-form offerings and won't win any design awards. However, they've done many higher-end custom finishes per request. Of course, that comes at a cost.
No longer any upscale finishes. Don't care where he came from, doesn't change anything. Not a fan. Everything is off the shelf. You or I could build an identical sub. Not so with JTR, Funk, Harbottle etc...
 

mj30250

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No longer any upscale finishes. Don't care where he came from, doesn't change anything. Not a fan. Everything is off the shelf. You or I could build an identical sub. Not so with JTR, Funk, Harbottle etc...

Ok, cool. I'd love to see an off-the-shelf B&C driver put into a similarly sized cabinet by a standard DIY'er and reach remotely the same level of clean output and extension while maintaining the same (or better) mid-bass performance. Feel free to share any examples as I might be interested in a buy.

Their amps are built in-house and use proprietary DSP. Most (all?) of their B&C drivers are custom-made for PSA. They aren't off-the-shelf with the exception of the IPALs. The 21" IPAL drivers retail for nearly $1900 ea. Then you need an amp suitable to drive it to a very strong <10Hz in-room extension, then the cabinet. Again, if you know a DIY'er who can best that for $3300 shipped and include a 5 year warranty, please send them my way.

Anyway, that's as far as I care to continue down this tangent.
 

Battlebeast

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Ok, cool. I'd love to see an off-the-shelf B&C driver put into a similarly sized cabinet by a standard DIY'er and reach remotely the same level of clean output and extension while maintaining the same (or better) mid-bass performance. Feel free to share any examples as I might be interested in a buy.

Their amps are built in-house and use proprietary DSP. Most (all?) of their B&C drivers are custom-made for PSA. They aren't off-the-shelf with the exception of the IPALs. The 21" IPAL drivers retail for nearly $1900 ea. Then you need an amp suitable to drive it to a very strong <10Hz in-room extension, then the cabinet. Again, if you know a DIY'er who can best that for $3300 shipped and include a 5 year warranty, please send them my way.

Anyway, that's as far as I care to continue down this tangent.
Then why ask questions if you don't want answers? ;)
 

mj30250

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Count Arthur

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I'm pretty sure I had that game on the Amiga. :)

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Beershaun

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Dirac target shape is like you mentioned with a small slope. However my problem is the sub is showing lot of dips or the measured response is not that great. In general I modify the target curve by 3dB max so that it stress amp that much.
Add a second rythmik 12 sub is your next step.
 

Ze Frog

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Typically, the subwoofer handles the low bass and the speakers handle the mid bass, depending on your crossover frequency.

I plugged my speaker ports. This reduced their group delay in the low frequencies and helped me to get better phase alignment with my subwoofer. This provided more bass impact in my system. The caveat is that plugging your speaker ports means the speakers won't play as low, so you may need to use a higher crossover frequency. I use 100 Hz and a 48 dB/octave slope.

I recommended to another person to try this, but his speakers did not respond well to the ports being plugged. So, it may or may not work for your system. How well it works also may depend on how much crossover tuning adjustment you have in your system. Also, be aware that if you move the crossover frequency too high with not a steep enough of crossover slope, the subwoofer will lose transparency and the bass will sound like it is coming out of it rather than in the sound stage. This depends on the crossover frequency, crossover slope, subwoofer placement, room characteristics, etc. So, you may need to experiment a bit.
The one thing that bothers me about plugging ports though is most of the drivers in today's speakers really don't have the parameters to get the best from a sealed enclosure. For my D.I.Y build it took me a lot of time and going through various driver's to find something with the ideal qts among other things.

Which leads me to the question, does plugging ports on a bass reflex design really do anything beyond stifling output? I get that's the aim, to attenuate the lower end, but always left questioning the knock-on effects. Wouldn't just high passing above port tuning effectively be just as good really?
 

witwald

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Subwoofers are hard enough to manage without the added complication of an uncontrollable and out of phase rear wave interfering with the front.
If that really were the case, wouldn't vented-box loudspeakers be a non-starter in general? Remember that the (usually) close proximity of the vent to the woofer means that these two sound sources are co-located at low frequencies to all intents and purposes. Of course, the transient response of a vented-box system is demonstrably worse than that of a closed-box system for the same –3dB cut-off frequency.
 

Keith_W

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If that really were the case, wouldn't vented-box loudspeakers be a non-starter in general?

Yup. To me they are out, though for slightly different reasons. The moment I see a port, I strike the speaker out as a contender. The only exception where I tolerate ports are computer speakers.
 

terryforsythe

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does plugging ports on a bass reflex design really do anything beyond stifling output?
1. Plugging the port lowers the group delay at the lower frequencies and makes the group delay less non-linear. With my speakers, this enabled me to get better phase alignment with the subwoofer in the crossover regions I experimented with before settling on a final crossover frequency. This resulted in a smoother frequency response in the crossover region and a tighter bass response.

2. Plugging the ports virtually eliminates noise and resonances coming out of the port. In some speakers the noise/resonances are worse than others. In my speakers plugging the ports resulted in a smoother frequency response up into the midrange frequencies.

As I noted, the downside is that you lose bass extension - the box volume with the port plugged may be a little large for an ideal acoustic suspension setup, which may result in the woofer being underdamped. You probably will need to crossover at a higher frequency than if you leave the port unplugged. Thus, you probably will want to use a very steep crossover slope.

As I also noted, plugging the ports may not work in all speakers. It worked for me, but somebody else reported it did not work for him.
 

terryforsythe

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When using a speaker without a subwoofer, I do prefer a bass reflex speaker (although I have not yet tried a transmission line speaker, which I do find interesting).

When using a speaker with a subwoofer, I prefer an acoustic suspension speaker for the reasons I explained above. In my previous speakers that were entirely DIY, I had a flat frequency response down to 60 Hz with an acoustic suspension design. They performed extremely well, but were too large for our present decor (my wife called them my "coffins"). Now I have smallish bookshelf speakers that originally had some issues, but I was able to transform them into well performing speakers for my music listening preferences. I was able to get good subwoofer integration with the changes, which included plugging the ports.
 
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rlal

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Add a second rythmik 12 sub is your next step.
If I get a 15 inch sealed Rhythmik will it be an issue? I mean one being 12 and other 15"?
The one I have is 12" but it is made by Salk and his cabinet is much bigger than Rythmik 12" sub woofer cabinet.
However 15" Rythmik is having uses 600W plate amp while other one use lower wattage.
 
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rlal

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Ok, cool. I'd love to see an off-the-shelf B&C driver put into a similarly sized cabinet by a standard DIY'er and reach remotely the same level of clean output and extension while maintaining the same (or better) mid-bass performance. Feel free to share any examples as I might be interested in a buy.

Their amps are built in-house and use proprietary DSP. Most (all?) of their B&C drivers are custom-made for PSA. They aren't off-the-shelf with the exception of the IPALs. The 21" IPAL drivers retail for nearly $1900 ea. Then you need an amp suitable to drive it to a very strong <10Hz in-room extension, then the cabinet. Again, if you know a DIY'er who can best that for $3300 shipped and include a 5 year warranty, please send them my way.

Anyway, that's as far as I care to continue down this tangent.
They use a 1900$ driver? That is impressive.
Very curious to hear this sub.
 

Ze Frog

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1. Plugging the port lowers the group delay at the lower frequencies and makes the group delay less non-linear. With my speakers, this enabled me to get better phase alignment with the subwoofer in the crossover regions I experimented with before settling on a final crossover frequency. This resulted in a smoother frequency response in the crossover region and a tighter bass response.

2. Plugging the ports virtually eliminates noise and resonances coming out of the port. In some speakers the noise/resonances are worse than others. In my speakers plugging the ports resulted in a smoother frequency response up into the midrange frequencies.

As I noted, the downside is that you lose bass extension - the box volume with the port plugged may be a little large for an ideal acoustic suspension setup, which may result in the woofer being underdamped. You probably will need to crossover at a higher frequency than if you leave the port unplugged. Thus, you probably will want to use a very steep crossover slope.

As I also noted, plugging the ports may not work in all speakers. It worked for me, but somebody else reported it did not work for him.
I've no doubt it works for all those things, have seen it proven many a time. My main thing with plugging ports to create a sealed response is more the driver being optimised for such as a lot of modern drivers have a low qts compared to what is ideally suited for a sealed enclosure. Ideally for a sealed design I prefer a qts of at least 5.0, admittedly that part is somewhat irrelevant here to a degree. Not many sealed speakers these days, so guess port plugging is as near as most will get to a properly sealed enclosure. It's odd, with correctly specced driver's you can get reasonable bass response, my bookshelves are 12 litres internal volume with an F3 of 60Hz, but sealed gives the impression of more bass by rolling off more gradually and easier to take advantage of room gain sometimes, so really quite surprised more manafacturers don't do sealed designs. I'm guessing it has to do with the fact higher qts driver's really aren't manufactured so much these days as the trend is towards bass reflex, but maybe more manafacturers should order to their own specs and create more sealed designs, especially in today's Hi-fi world where subwoofers are a lot more common than they once were, seems they are missing a trick here to be honest.
 

Beershaun

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If I get a 15 inch sealed Rhythmik will it be an issue? I mean one being 12 and other 15"?
The one I have is 12" but it is made by Salk and his cabinet is much bigger than Rythmik 12" sub woofer cabinet.
However 15" Rythmik is having uses 600W plate amp while other one use lower wattage.
I personally think it will be fine. The main limitation you will have is that Dirac will not be able to calibrate them independently. You can do that manually to a certain degree. You'll need to adjust their levels to 72db each at whatever the Dirac calibration volume is. So you achieve 75db total when they are being calibrated together (or whatever the calibration spl is supposed to be). Then You'll need to set their phase angles manually with the main left/right speakers. You can do this with REW by playing a tone at the crossover frequency to both the main speaker and one sub then adjusting the phase angle to the max spl REW records. Repeat with the second sub. Enjoy!
 

terryforsythe

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a lot of modern drivers have a low qts compared to what is ideally suited for a sealed enclosure.
It depends. A Qts of 0.40 works well for a second-order Chebychev equal ripple response (Qtc = 0.8) acoustic suspension speaker. A Qts of 0.40 also works well for a vented enclosure with a SC4 alignment with a QL of 7.

prefer a qts of at least 5.0
I have never used a woofer with a Qts anywhere near that high. The last acoustic suspension speakers I built myself used woofers with a Qts of around 0.33 for a second-order Butterworth alignment (Qtc = 0.707). The last ported speakers I built myself used woofers with a Qts of around 0.40 for a SC4 alignment (QL = 7).
 
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terryforsythe

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so really quite surprised more manafacturers don't do sealed designs.
Most people buying speakers don't know any better. They listen to the speakers and the one with the most bass and top end sizzle typically sounds better to them, not knowing that ported speakers can be more difficult to get phase aligned with a subwoofer.

KEF does provide port plugs with some of their speakers. I don't know whether any other speaker manufacturers also provide plugs.
 

jhaider

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No longer any upscale finishes. Don't care where he came from, doesn't change anything. Not a fan. Everything is off the shelf. You or I could build an identical sub. Not so with JTR, Funk, Harbottle etc...
Admittedly I don't have an encyclopedic knowledge of their offerings, but I'm not aware of a dual voice coil 18 from B&C.

Can you show me that on their website?
 
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