Peerless XXSL 10" Small enclosure

[KI]

Hi!

I'm about to make two small subs using the 8ohm XXLS 10" from peerless (830843). I've calculated that an internal volume of 31,5 liters will be sufficient. I would perfer 40-50 liters, but "space limitations" persuade me to go even smaller; 31,5.

My calculations tells me that with a +6db boost @ 25hz and lowpass @ 40-50hz I will end up with a not-ideal, but ok curve (it will require some bad-*** amp)

Do any of you agree, or is it just silly to even think about it?

and by the way; I'm thinking maybe a PR as well; The peerless 10" XLS passive radiator. Will have some advantage over the closed box? My calculations show a slightly increase in sensitivity, but about the same response curve. I plan to make a hole for the PR, but put a MDF piece there to start with..., and possibly make a "signature" versjon later when I get the $$$ to buy me the PRs. ... just like Audiovector and their Mi-sub and Mi-sub signature.

Silly, or ok? hot or not? yay or... no?

I'm not looking for a killer sub..., only some nice tight bass...

Yes, I did search the forum.., but found only projects involving bigger enclosures.

[KI]

btw; I just started the fabrication of the enclosures..., so if it's completely stupid... I'll be sorry to hear that....

Either way; Here are some pictures of the front and back baffles... and the "dymmy" that can be replaced by a PR later on.

Some images ..:

[Inductor]

Hi,
I did some exercises for you. This might be a good start:
one is an isobarik (w/two subs) and 63L (using the 2x31.5L), check the blue line;
another is a double enclosure (1x31.5L), one sub with passive radiator (green line), this for one box and I used here the XLS-269-S265 with 265gr.
http://www.bmm-electronics.com/Produ...roduct_ID=3341

(note that PRs are not optimized or calculated for optimum size and weight, were just introduced on WinISD software. Protect under 18Hz for max. cone excursion in both cases)

[bjorno]

…I'm about to make two small subs using the 8ohm XXLS 10" from peerless (830843). I've calculated that an internal volume of 31,5 liters will be sufficient...

A very good driver supposed to be used in a sub-optimized IMO too small cabinet.

…I would perfer 40-50 liters, but "space limitations" persuade me to go even smaller; 31,5…

IMO, Good use of this driver starts with a closed box of no less than 58 L.

…My calculations tells me that with a +6db boost @ 25hz and lowpass @ 40-50hz I will end up with a not-ideal, but ok curve (it will require some bad-*** amp)…Do any of you agree, or is it just silly to even think about it?…

Low passing at 40-50 Hz precisely where f-3dB and fc are situated makes the performance of this design even worse and + 6dB at 25 Hz as stated, will be +12 dB at 12.5 and so on unless you consider use a LT or similar technique to prevent excessive cone excursions at very low frequencies.

…and by the way; I'm thinking maybe a PR as well; The peerless 10" XLS passive radiator. Will have some advantage over the closed box?…

No, not with the suggested driver and no other advantage than the possibility to use a smaller box, and IMO will suffer degraded sound quality even if the more suitable driver 830842 is used.

…My calculations show a slightly increase in sensitivity, but about the same response curve. I plan to make a hole for the PR, but put a MDF piece there to start with..., and possibly make a "signature" versjon later when I get the $$$ to buy me the PRs. ... just like Audiovector and their Mi-sub and Mi-sub signature…Silly, or ok? hot or not? yay or... no?…I'm not looking for a killer sub..., only some nice tight bass...

IMO your design suggestion works contradictive to tight bass, see picture 1(2).

…Yes, I did search the forum.., but found only projects involving bigger enclosures…

Of course, because most people here are hunting for good sounding subs and using LT to shrink the need for larger volumes, see picture 2(2).

b

1(2)

[bjorno]

2(2)

[sreten]

Originally posted by bjorno

Low passing at 40-50 Hz precisely where f-3dB and fc are situated makes the performance of this design even worse and + 6dB at 25 Hz as stated, will be +12 dB at 12.5 and so on unless you consider use a LT or similar technique to prevent excessive cone excursions at very low frequencies.
1(2)

Hi,

I suspect the intention is a Q=2 high pass filter @ 25Hz.

/sreten.

[KI]

Well.... That sucked.
That explains why I've never seen this driver in such a small box before...

Well... Even if it's against all reason..., and the executives at Peerless will turn in their beds; I'll try. The only thing I'm loosing is some boxes that seems to turn out better than anything I've ever made before... And the work involved... (but hey; its fun though!).

And maybe, some day; I might find some drivers who will acctually enjoy the somwhat tight enviroment..., and someday I might not give a crap about the size and make them big enough to make the drivers really play like they want to.

Thanx for providing me with this information. I have never really understood most of the T/S parameters..., but I'm really trying

Anyway; I'll keep posting pictures while I'm working.., so please continue to read this post and please ignore the foolishness of making a box not suited at all.

Thanks!

[KI]

Originally posted by sreten

Hi,
I suspect the intention is a Q=2 high pass filter @ 25Hz.
/sreten.

The intention is "6db boost" which are to be found on most sub-amps like the hypex ones. Correct use of this, together with the lo-pass filter could possibly work to my advantage?

(I might also add that I bought the drivers some time ago..., but they are just laying here... And I've got the amps.., so why not give it a try?)

[KI]

Originally posted by bjorno

IMO your design suggestion works contradictive to tight bass, see picture 1(2).

Damn...

Originally posted by bjorno


Of course, because most people here are hunting for good sounding subs and using LT to shrink the need for larger volumes, see picture 2(2).

b

... Ok. So you're saying that with a LT and a rather potent amp, this might still have some potential? ... Or will it still give me bass that has nothing in common with the words "thight" and "funky"?

[KI]

Am i completely wrong assuming the Peerless XLS driver would love 30liters and a PR with a slightly increased mass?

If not; maybe I should get myself a couple of XLS instead of XXLS. I thought they were quite similar... but obviously not....