Art Welter (weltersys) built a ppsl with those drivers. Aren't as nice as some of the better options from B&C and Eminence.
Yes,
Art Welter made some PPSL with those. Please read his comments before deciding to use this driver.
http://www.diyaudio.com/forums/subwoofers/255010-compact-2x15-ppsl-using-dayton-pa385-8-drivers.html
" I recently built some PPSL cabinets using Dayton drivers, the measured distortion was higher than non-PP designs I had built using Eminence and B&C drivers. Oh well."
Art Welter made some PPSL with those. Please read his comments before deciding to use this driver.
http://www.diyaudio.com/forums/subwoofers/255010-compact-2x15-ppsl-using-dayton-pa385-8-drivers.html
" I recently built some PPSL cabinets using Dayton drivers, the measured distortion was higher than non-PP designs I had built using Eminence and B&C drivers. Oh well."
Last edited:
They had to compromise on those drivers SOMEWHERE to get them to the $200 price point. If I were going to try to use "cheap Dayton drivers" I'd be using their under-$100 class. I wonder how two of the stamped frame 15's (PPSL or otherwise) would hold up against one of those 385's. I'll venture to guess the only downside would be cab size.
I was unaware of Art's experience with these drivers; T/S looked decent on paper. Disappointing. OTOH, plenty of audio customers seem to equate harmonic distortion with a sense of loudness & power. My friend / business partner doesn't like the low-distortion sound of my 4 PPSL subs ( Kappa Pro 15LF), but they'll thud you in the chest at the rear of a large auditorium, in spite of their Xmax.
Last edited:
I don't really know anything about the dayton stuff. As a guitarist and bassist, I'm really familiar with eminence, but don't know anything about dayton. I've heard B&C mentioned before but am not familiar with them either.
Is a PPSL design going to fit into the space I have to work with?
Is a PPSL design going to fit into the space I have to work with?
"I don't really know anything about the dayton stuff. "
Dayton is a house brand from Parts Express. They source produts from various vendors, TC Sounds, Eminence, Tangband, etc. The better Dayton is very, very good. Even the less expensive Dayton is quite good for the money, better than the inexpensive house brands dfrom MCM. B&C makes quality product, although it can be quite expensive. B&C does not have as good a warranty as Eminence though.
"Is a PPSL design going to fit into the space I have to work with? "
PPSL is a design concept to reduce distortion. It may be applied to just about any kind of loading, sealed, vented, open baffel, etc. You may adjust dimensions to fit your available space, just make sure the net volume is the same. I have done designs from 8" to 18", dual and quad drivers, and have even seen someone do a 32 driver array with 18's!
Dayton is a house brand from Parts Express. They source produts from various vendors, TC Sounds, Eminence, Tangband, etc. The better Dayton is very, very good. Even the less expensive Dayton is quite good for the money, better than the inexpensive house brands dfrom MCM. B&C makes quality product, although it can be quite expensive. B&C does not have as good a warranty as Eminence though.
"Is a PPSL design going to fit into the space I have to work with? "
PPSL is a design concept to reduce distortion. It may be applied to just about any kind of loading, sealed, vented, open baffel, etc. You may adjust dimensions to fit your available space, just make sure the net volume is the same. I have done designs from 8" to 18", dual and quad drivers, and have even seen someone do a 32 driver array with 18's!
Ok awesome, thanks for the info! I've been plugging parts express drivers into hornresp and trying to see what would work best for my situation. I'm starting to get a better feel for how the software works after reading through some things and I feel a lot more confident about designing enclosures.
I think I would have enough space to put four 15" or 18" drivers in vented enclosures. Would building two drivers into one box in a PPSL arrangement benefit me in any way other than reduced distortion?
I think I would have enough space to put four 15" or 18" drivers in vented enclosures. Would building two drivers into one box in a PPSL arrangement benefit me in any way other than reduced distortion?
The plenum adds extra occupied space to a vented (or any) design, but the benefits are worth it, IMO. The plenum in my version is 15.75" x 16" x 7.5" interior. If you can make a fit, do it.
If mounting the PPSL in an alcove that's essentially flush with the wall you will pick up some dB's over a straight box due to the compression in the slot.
Nelson Pass built a OB with a slot (push-push, not push-pull) that tested with about 2.78dB over a flat baffle. The bigger the baffle, the lower in frequency the gain from the slot extends, so an alcove with a wall on either side will show some real gain. How much, you would need to build it and then measure it. I just ignore it, and if I get some gain, great, if I don't, well I didn't figure it in to start with.
Nelson Pass built a OB with a slot (push-push, not push-pull) that tested with about 2.78dB over a flat baffle. The bigger the baffle, the lower in frequency the gain from the slot extends, so an alcove with a wall on either side will show some real gain. How much, you would need to build it and then measure it. I just ignore it, and if I get some gain, great, if I don't, well I didn't figure it in to start with.
4x18" ported cabs will just about do what your 4x KSubs will do.
This is not an improvement.
I'm pretty sure I've said this before, but you simply need more. PPSL doesn't magically give you more output. Good horn-loading does, at the expense of a cabinet size.
For a clear win, 4x 18" THs** will beat the KSubs, probably by 6dB or so. 8x 18" THs will give more like 12dB if you have the power. That sounds just over twice as loud, which is what I think you ought to be aiming for.
** I mean good 18" drivers. They don't need to be top-of-the-line, but will need healthy Xmax (8mm or more) and power handling.
The cheap Eminence stuff will give you a ~3mm Xmax. If you double excursion, you get 6dB more output. A single driver with 12mm Xmax would keep up with 4x cheap cabinets.
When you consider the amount of work and money extra cabinets would cost, using a small number of very good drivers starts to make a lot of sense.
Chris
This is not an improvement.
I'm pretty sure I've said this before, but you simply need more. PPSL doesn't magically give you more output. Good horn-loading does, at the expense of a cabinet size.
For a clear win, 4x 18" THs** will beat the KSubs, probably by 6dB or so. 8x 18" THs will give more like 12dB if you have the power. That sounds just over twice as loud, which is what I think you ought to be aiming for.
** I mean good 18" drivers. They don't need to be top-of-the-line, but will need healthy Xmax (8mm or more) and power handling.
The cheap Eminence stuff will give you a ~3mm Xmax. If you double excursion, you get 6dB more output. A single driver with 12mm Xmax would keep up with 4x cheap cabinets.
When you consider the amount of work and money extra cabinets would cost, using a small number of very good drivers starts to make a lot of sense.
Chris
"PPSL doesn't magically give you more output. "
True, other than the small gain in the slot (above the baffel-step frequency). I generally choose drivers with a Qts around 0.312 so I can do a 6th order vented system.
A 2 cu ft 2nd order sealed box with an F3 of 30hz can only be 0.18% efficient (84.55dB).
A 2 cu ft 4th order vented box with an F3 of 30hz can only be 0.36% efficient (87.56dB).
A 2 cu ft 6th order vented box with an F3 of 30hz can only be 0.90% efficient (91.54dB).
From examining various equations for efficiency and LF cut-off I have concluded the optimum driver for the highest efficiency, smallest box, and lowest cut-off would have a Qts=0.312 and be a 6th order system with an Fb=F3=Fs=Faux with the filter (Faux) having a Q=2.
I can address alignment jamming (using non-optimum drivers) if desired.
The maximum efficiency for multiple direct radiators is on the order of 25%, where a FLH is on the order of 50%, or 3dB higher.
If you have unlimited space, the FLH makes sense.
A pair of the Eminence made Dayton 295-120 12's have the same output as an 18 with 8mm x-max, at about half the cost, and less distortion (due to PPSL).
"A single driver with 12mm Xmax would keep up with 4x cheap cabinets."
Two 6mm drivers will have the same output as a single 12mm driver, and higher efficiency.
True, other than the small gain in the slot (above the baffel-step frequency). I generally choose drivers with a Qts around 0.312 so I can do a 6th order vented system.
A 2 cu ft 2nd order sealed box with an F3 of 30hz can only be 0.18% efficient (84.55dB).
A 2 cu ft 4th order vented box with an F3 of 30hz can only be 0.36% efficient (87.56dB).
A 2 cu ft 6th order vented box with an F3 of 30hz can only be 0.90% efficient (91.54dB).
From examining various equations for efficiency and LF cut-off I have concluded the optimum driver for the highest efficiency, smallest box, and lowest cut-off would have a Qts=0.312 and be a 6th order system with an Fb=F3=Fs=Faux with the filter (Faux) having a Q=2.
I can address alignment jamming (using non-optimum drivers) if desired.
The maximum efficiency for multiple direct radiators is on the order of 25%, where a FLH is on the order of 50%, or 3dB higher.
If you have unlimited space, the FLH makes sense.
A pair of the Eminence made Dayton 295-120 12's have the same output as an 18 with 8mm x-max, at about half the cost, and less distortion (due to PPSL).
"A single driver with 12mm Xmax would keep up with 4x cheap cabinets."
Two 6mm drivers will have the same output as a single 12mm driver, and higher efficiency.
- Status
- Not open for further replies.