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Item: pair passive 30hz tapped horns, Will Cowan design, built by Paul Spencer with brand new 12" Eminence Definimax driver Location: Kinglake West, VIC Reason selling: Not using. Condition: DIY, never used. Pickup only, COD Price: $650 for both horns and both drivers. Firm. I had Paul build me two of these last year but my plans for speakers took a different direction so haven't had the need for these. The drivers were bought brand new and haven't been installed, other than Paul briefly installing one to measure the finished subs. Some plans and graphs can be seen here http://www.cowanaudio.com/th.html The finish is fairly rough, form ply, the subs designed to be out of sight, might benefit from a sand and paint. Here are Paul's blog posts from the building of this actual pair https://redspade-audio.blogspot.com.au/2016/02/30-hz-horn-sub-continues.html https://redspade-audio.blogspot.com.au/2016/02/30-hz-horn-sub.html

Yeah I’d use a plate amp on the bass divers. If you like festive levels with a 6W amp I’d consider a passive line-level HP xo before the amp?

I've been using the Betsy's for a few months now in 60cm wide OBs with Eminence Beta 15A bellow 100hz or so. I'm quite happy with them, even compared to some much more exotic OBs I've run in the past. But I likely wouldn't use them without the bass driver, nor probably without EQ. I've also added a cheap rear upward-firing super-tweeter with good results.

I've done both configurations over the years, for music and HT. I tend to prefer in-wall all else being equal, mainly for the lack of clutter. Though I have dipoles in the music room which obviously don't work as in-walls. The main difference might be down to whether the the particular driver/crossovers that make you prefer one brand/model over another are offered in in a comparable in-wall version, i.e. same cept for the box. The Kef R-series in walls seem to have the same driver as their floorstanding counterparts, but the Q-series in-walls appear different to the Q-series boxes. Main difference sound quality wise is lack of soundstage depth with in-walls. On the plus side the bass response is smoother as you don't get bounce off the back wall creating destructive interference. I imagine their might be some losses with in-wall due to poor coupling if fixed to wobbly stud/plasterboard. You could anchor to brick behind possibly. Cheers B

Thanks all for your replies.

Anyone know of a decent entry-level roll of about 100m for wiring 11.1.4 behind plasterboard walls? I've seen a Selby cable for $1.50/meter. Cant find any rolls of similarly priced Mogami or Canare. Any options appreciated. Cheers B

Maybe my bad drawing explains better

Cheers, that clears things up in my head. By 'simplicity' I was only considering the box and cable count - I want some speakers I can easily drag outside on a sunny day. One last question if you don't mind Dave - I've currently got some baffles which low and wide (60cm wide) with cutouts for a 15" and 8", with space for more drivers to the side of the 8" but not above. I'm thinking of a LX521 type setup with tweeter above a 4" mid as intended, but with these next to the 8" driver rather than above, and then routing out cavities to either side of 4/1" and 8" such that the baffle width surrounding each driver is the same as in the LX521 build, say 1" or whatever it is. My question is, if there is only enough width to the entire baffle such that I only fit in a say 1.5" air gap between the 4"+1"and the 8" driver adjacent to it, is this 1.5" air gap enough for the low frequencies at the low end of the 4" and 8" drivers' pass bands to wrap around such that the out pf phase waves meet and cancel out as desired? I'm guessing there must be a too narrow, where the longer waves (120hz) don't see the air gaps and instead see a 60cm wide baffle rather than 1" baffle...any thoughts? Cheers B

Thanks for your reply Dave. I do usually think its good advice to go with established designs, but if I the LX521 3-way is not still available I might still consider DIY 3-way for simplicities sake. I understand the dispersion and excursion issues of mating an 8" with 1" tweeter, but would only consider a 4-6" for mid. The dipole peak issue I don't understand too well (can this not be EQ's away with PEQ?) I have some Eminence Beta 15's I could use, which would stretch high enough to meet a 6" mid (300-600hz?), and I wouldn't have thought the excursion of the 6" would be an issue with 4th order HP at 300-600hz? The polars of the 6" Satori it only starts to beam at 1.5K. The SB tweeter has been proven good down to that low with steep slopes. Where would the major drawback in this design be - is the dipole peak of a 6" going to be a problem between 300/600 and 1.5K. Or a 15" beaming by 600hz? Or excursion of the 6"...? Thanks again.

I'm tossing up between a 4-way OB, either Linkwitz LX521 or Nao Note II RS, vs a 3-way. I'd prefer 3-way for simplicities sake so I can get away with a 3-way Hypex Fusion plate amp. I'm trying to understand if the 4-way offers appreciably better off-axis polar response, with XOs say 120/1000/5000hz for 12"/8"/4"/1", vs a 3-way with XOs 300/1.4K for 12"/6"/1" drivers (the mid and tweeter in mind are Satori MW16 and TW29R). Thanks for any input. B. I believe LX521 can be done as an active 3-way with passive xo between lower and upper mid, which would be another option, though I can't find any opinion on this vs the active 4-way LX521.

Item: Meanwell hrpg-450-15 Location: Price: $100 Item Condition: few scratches, operationally perfect Reason for selling: no longer using Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: https://www.meanwellaustralia.com.au/products/hrpg-450 I bought this new, to power a car amp setup at home.

Thanks kelossus. Have a look at the manual which has a link to the System Architect program, download to try. 5021481_SPEC_MNL_XTi2_OPERATION_06-12_original.pdf

I believe so, but you'd better look at the online manual. I configured it for a 80hz low pass, and I think likely a 20hz high pass, but I can't recall as it was a year and a half ago. I had to borrow my dads desktop PC to configure which was a pain as the software doesn't run on my Mac, otherwise I'd try out a bandpass now to confirm for you.

Item: CROWN XTI 1002 DSP amplifier Location: Kinglake West, Vic Price: $350 Item Condition: Excellent cosmetically and zero operational issues Reason for selling: not using Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: No original packing. Prefer pickup but could ship at buyers expense. Have original box. Pictures:

Item: pair passive 30hz tapped horns, Will Cowan design, built by Paul Spencer with brand new 12" Eminence Definimax driver Location: Kinglake West, VIC Reason selling: Not using. Condition: DIY, never used. Pickup only, COD Price: $650 for both horns and both drivers. Firm. I had Paul build me two of these last year but my plans for speakers took a different direction so haven't had the need for these. The drivers were bought brand new and haven't been installed, other than Paul briefly installing one to measure the finished subs. Some plans and graphs can be seen here http://www.cowanaudio.com/th.html The finish is fairly rough, form ply, the subs designed to be out of sight, might benefit from a sand and paint. Here are Paul's blog posts from the building of this actual pair https://redspade-audio.blogspot.com.au/2016/02/30-hz-horn-sub-continues.html https://redspade-audio.blogspot.com.au/2016/02/30-hz-horn-sub.html