SB Acoustics SB20FRPC30-8 (8" Fullrange Cheap Monster II)

Hello nandappe, thank you for reply. Items ordered on line.

Can you share whether you do internal bracing and if affirmative, how do you do it.?

Secondly, how to adjust the padding amount? Via the hole for the speaker or via the detachable rear panel?
I am considering leaving the top panel detachable. Is there any negative to consider?

The carpenter will be using 18 mm pine wood

Reinforcement is not necessary if 18 mm thick pine is used.
Fine-tune the size of the boards, giving priority to the internal volume and internal dimensions.

Adjustment of the sound absorbing material can be made later, either on the back or top board.
No gap is preferable, but I don't care about 0.5mm.
Good idea, Leif.
A few examples are allready show in this thread.
For myself mentoined the version in a 35l cab - driver pimped with a magnet. Works fine, x-over ist close to finished.
The 60l cabinet is still growing - hope to get it ready during Easter.
For those who are impatient or a little snoopy: take a breath here:
The finished version will be presentet here.
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I'm using this driver in an OB configuration so can't tell much about the behavior as a woofer, but very much as a mid/high driver. And as such, they are great. Very clean sound with great mids and crisp and clear highs. My only issue is (maybe because of installing it many times during trials) some mechanical noise (maybe resonances?) from one of the drivers so I will replace it as soon as it will be available again from my source.

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Thanks for that. I'm always on the lookout for a nice driver to put in my favorite design, MLTL. That one sims very well in a very tight package.
Myself, I would probably cross it at around 3kHz.

Not cheap, but looks really good. I'm sure it sounds just as good as it looks!
With that flat response you could use 1st order crossovers, if you are into that. I prefer 1st order crossovers but they are so very difficult to realize. Active is the way to go these days.
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I don't Know a best drum track.
Introducing My Favorite 4 CDs.
I used Helge Lien this time.

Good Vibes-Jazz at the Pawnshop3 / ARNE DOMNERUS GROUP (PRCD9058)
The Best of Fourplay (EVSA765M)
Live at The Village Gate / CLARK TERRY (CHESKY JD49)

Oh, Baffle Step Correction Circuit.
I have never used it.
I’m using Pandora to listen to the Helge Lien trio.
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With that flat response you could use 1st order crossovers, if you are into that. I prefer 1st order crossovers but they are so very difficult to realize. Active is the way to go these days.
Yep.but at least, tweeter integration is easier than woofers at 1st order.

After seeing some reviews, them crossing as high as 8kHz, I would look into crossing between 5~8kHz now. It does look like a very good driver.
A few updates since my last post.

First I changed the baffle from pine to a slightly smaller version made from 18mm MDF and 'finished' with self-adhesive vinyl flooring incorporating a 2mm rubber layer - has resulted in much better looking (IMO) speakers that are acoustically more inert.

The most recent step was to add 2 x SB Acoustics SB20PFCR30-8 wired in parallel in each baffle. Myself and my son fitted them on Friday night and they are actively driven (in stereo) and low passed at about 130hz with a 12db slope.

These speakers no longer need any bass support from sealed box woofers and they have a lovely, tangible bass that sounds very much like real instruments. They produce excellent punch at low amplifier settings in the small office. Eventually they will be in a room twice the size (circa 3m X 5.5m). If need be I will run a pair of SB Audience Bianco OB 12s or even 15s in H frames off a plate amp to add a bit extra in the larger room.

I've tested them (full range driver only - no passive crossover) with an Arcam A18 (now set to flat) and an AVA Media Maestro 50 that produced great results. As said, the woofers are driven actively so just require slight tweaks with a room/amp change.


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