Alpair12P gen2 standmount speakers

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Didn't know they were already assembled, glued up and ready to go.

If it only comes down to how they look, i'll guess you could double up the top panel to make up for the 16mm's then cover it all up by veneering the whole thing?
 
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My basic understanding is driver (mid-bass, woofer or wide bandwidth), location on the baffle affects severity of standing waves in a "untreated enclosure".

Because your driver is so close to the top panel, i would be inclined to listen and compare as is and with a sheet of Deflex installed inside the top panel. Afterwards you could also place one behind the driver. With each alteration listen to taste, it could go either way, idk?

- this would work, The Madisound Speaker Store
- or this, Deflex 7" Power Pad Pair 268-242
 
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hi, thanks.
however, the driver is still quite low considering the box. With the alpair, the surround and the plastic basket is so large that even with my mistake, the cone is still about a inch and half from the top panel. I dont hear any problem. Ive stuffed the back and the sides panel, leaving the top and bottom and the baffle without lining... Should I put more, less?

Actually, I'm here to tell how good the sound is. The ports are not even installed yet,. but DAMN! I really like the sound. The bass goes deep enough, just perfect for my tv set/computer needs. The fonkens fe127 definitely wasnt going deeper enough, but the alpair do! I'm relieved, that was my major concern. For most basslines, I hear every note without problems, this is where the fonkens just couldnt. Bass drum are punchy and detailed. The bass and upperbass is detailed, really detailed for a 6 1/2 driver, im impressed, highly impressed. The bass is definitely great and its a relief. It goes deep enough for my needs, and Im not even in the 200 hours of burn in...
The midrange is detailed, smooth, beautiful honestly. The highs are laid back and I dont hear the normal aggressivness. I'm really happy with the sound.

I really like the musical presentation. The alpairs 12p are really musical drivers. They really make you forget about hifi and allows you to listen to the emotion of the artist. Its a FUN driver to listen to and definitely hifi. You hear the room in where the musicians were. Your really in the audience listening to a band, nothing like a forward presentation. I hear echo and reverbs I never heard before. Its a real intimate driver and highly musical, with a flat response. Its a really detailed driver and musical.
The xmax limitation was of a concern, but I realize that to go to the xmax limit, I have to play them really loud, which I wont anyways.


Thanks Mark, this is definitely a impressive little driver!

cheers
 
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You should at least have sound absorbing material installed on one opposing wall. For example, if you have nothing on the top panel, you should have the bottom padded. Adjust stuffing to taste.
I dont know, the thing is that I have read how a BR enclosure needs to resonate a bit and that too much lining can muffle the sound.
I have also read that BR need really minimal lining and stuffing...
 
Wall lining is needed to absorb higher frequency reflections. The resonating frequencies about which you may be concerned are much lower. There are really quite few practical materials that when used as a wall lining in a speaker cabinet of small dimensions would impact bass resonances. Most are only effective at higher frequencies. I don't have a lilnk to support this, but quite a bit of research was done in the 80s and 90s.

There is a significant difference between wall lining and box stuffing.
 
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Wall lining is needed to absorb higher frequency reflections. The resonating frequencies about which you may be concerned are much lower. There are really quite few practical materials that when used as a wall lining in a speaker cabinet of small dimensions would impact bass resonances. Most are only effective at higher frequencies. I don't have a lilnk to support this, but quite a bit of research was done in the 80s and 90s.

There is a significant difference between wall lining and box stuffing.
okay, so I should line all the walls? and also stuff foam in it?
Whats your experience with lining BR enclosure? I have read quite often that contrary to closed enclsoure, BR rely on controlled resonance in the box and so that its not recommended to line all walls at all.
 
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okay, so I should line all the walls? and also stuff foam in it?
Whats your experience with lining BR enclosure? I have read quite often that contrary to closed enclsoure, BR rely on controlled resonance in the box and so that its not recommended to line all walls at all.


I'd still be inclined to lightly line the walls with 1/2" felt, etc - at the very least the top and back panels - and adjust stuffing fill levels "by ear".
Now you're gonna ask "what does that mean, and what's the consensus on best material for stuffing ;)

answer to the first is "you'll know it when you hear it", :rolleyes: and the second is - you gotta be kidding:D - I'd suggest avoiding any of the foams, and frankly my only experience with Deflex pads about 10yrs ago (Hammer Dynamics Super 12 "kit" ) was it didn't help all that much.


Keep in mind that the tonal balance will likely change considerably with break-in / usage, and you may need to add more as time passes . Fortunately, the A12P's through hole is large enough, and the BR enclosure small enough that you can easily access the full interior (unlike something like the FH3)
 
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I just installed the ports. I'm amazed by the amount of bass those speakers are showing. The bass is full and detailed, precise, fast. I'm really surprised, I didnt thought this was possible from such a small enclosure.
I do not even need sub, even for jazz. The quality of the bass is so great. It wont shake my house, but it punches pretty good. It start to roll off probably quite a lot after 40hz. but from 50hz, its probably flat since my room is small so I probably have a little bit of gain in the 50hz region. Seriously, I didnt thought this was possible from a 6 1/2 inch driver.
This is one special driver, really intimite and musical presentation. It just draws you to the music. Really happy!
 
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hi everyone
little update
I have taken the measurments of the alpair 12p. Ive attached the measurments.
They show me basically a problem from 150hz to 600hz. Ive apply EQ (using Electri-Q) in the problematic area and those speaker have come to life. The sound is much more balanced and the presentation have much more presence du to the upper bass and lower midrange EQ. I recommend everyone who has build those speakers to add around 3 db at 150hz, 3 db at 300 and 500hz, or something like that, the presentation is much more involving.
 

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Sometimes even less than a foot of change of placement, particularly in regard to all boundaries, can make substantial differences in both measured and perceived response at listening locations.

As Scott says, the room dominates, and while acoustic treatments are certainly available to tame / smooth bass response, they can often occupy far more space than is acceptable when WAF constraints apply.
 
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the measurments were taken around hallf meter away from the drivers, i doubt the room is having a effect. ive taken several measurments and close mic'ed, the response is really similar... the measurments taken at listening position is really different, but the one iv attached is closed mic.
i think the measurments look quite nice, and by applying a bit of eq at 150 hz, 300hz, 500 hz, sound is better.
 
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