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I pinched this info from my 'system' thread in the hope that it might encourage others with moderate systems and tricky rooms to try some room treatments. I recently moved into our new house with dedicated audio room. The room is 3.5m x 5.4m x 2.6m and during construction we added some 'upgraded' Bradford SoundCheck wall insulation. The room is carpeted but has no lounges or soft furnishings, and minimal hard furnishings. I recently upgraded to some PMC GB1i small floorstanders and an audio-gd ES9018 DAC (NFB3(2014)). Whilst I was happy-ish with the PMCs, I felt that the imaging and bass wasn't as good as I had expected. I realised from day dot that this room was pretty average acoustically given the lack of soft furnishings for absorption and hard furnishings for diffraction. There's a bit of slap echo, and I feel there is just a but too much reverb and smearing of the sound stage. The bass was a tad woolly at times. The PMCs were clearly being let down by the room. Coupled with my new audio-gd DAC, I wasn't 100% satisfied with the sound. SOOOOO... with a tight budget in mind, I decided to tackle the room in a simple and cost-effective way. I managed to grab two charcoal/black 2400mm x 1200mm x 50mm sheets of Polymax XHD direct from Martini Industries at Ingleburn, south-western Sydney (15 minutes from where I live). http://www.polymaxinsulation.com.au/downloads/Polymax_MDS_Absorb_Data_Sheet.pdf Martini had two sheets left over from a recent job, and were kind enough to cut each big panel into 3 x 1200mm x 800mm panels on their industrial cutter for ease of transport. All six of the smaller sheets fitted into the back of my Mazda 6 with the seats folded down, meaning I didn't need to stuff around with a trailer or van. The pricing was dirt-cheap too - it worked out at $20 per 1200mm x 800mm panel! At this price, there's no excuse for NOT grabbing some and seeing what it does to your room. If anyone needs contact details, Ben Mentiplay is the bloke I dealt with at the Ingleburn office. I chose the 50mm as the thickness suited my intended use as side and rear wall absorbers, as well as allowing them to be doubled-up to become XHD 100mm if I wanted to experiment with absorbers that performed better at very low frequencies. A big benefit of the Polymax XHD is its stiffness. It will stand perfectly upright against a wall with no sagging. I could quite easily get away without framing these panels, such is the quality of manufacture and cutting. I will, however, do something regarding framing and/or covering some day so that they blend in better with the decor. Interestingly, the Absorb XHD is manufactured using the 'card and cross-lap' method which Tontine used to use for their Acoustisorb many years ago, before switching to the 'air lay' process which is faster but less consistent and results in varied density throughout the product. One SNAer has encountered issues with the Tontine in a professional environment and only uses the Absorb as a result. Apparently, the published stats for the Tontine product are also based upon the old product from a few years ago (cheeky!) rather than the newer 'air lay' product which doesn't perform quite as well. It's amazing how much background and technical info there is on pro audio forums out there. I had a bit of a listen with some familiar tracks, and then embarked on some non-scientific panel placement. I basically replaced some of the temporary panels and foam squares which I had placed at the first reflection points on the side wall, and on the rear wall elevated behind the listening chair. These were thin panels and your typical acoustic pyramid foam which did help a bit with slap echo, but little more. I also plonked a panel behind each speaker (this space was previously bare) Cue the music... and whoaaaa, what do we have here? The improvement in reverb and echo was clear from the get-go. Imaging snapped into place, and subtleties which were previously masked are now clear and distinct. The sound is more coherent. From what I can tell, these panels have struck a pretty good balance between taming the ills of the room, yet allowing it to sound natural and still a tiny bit 'live'. Measurements may tell a different story, of course, but I'm very happy! This is as good as I KNEW my system could sound. Gone are my concerns about the PMCs not quite living up to expectations, and likewise, that lingering doubt in the back of my mind that the audio-gd ES9018 DAC was too bright and not synergising with my rig. It's not the gear... IT'S YOUR ROOM, STUPID!! Colour me impressed! For minimal expense, the performance of this room has been drastically improved. One day I might arrange for it to be measured properly, but in the interim, I am absolutely stoked with the outcome. Now... let's see what wifey says when confronted with these black monoliths!

Hey guys, I have recently decided to embark on a DIY bass trap build.. It seems most people in Australia have used the Polymax Absorb XHD 100mm batts. I have just contacted my local insulation store and they stated that the Polymax will take at least 2-3 weeks to build and get shipped to the Gold Coast. The guy I spoke to suggested the Bradford Supertell Glass Wool http://www.bradfordinsulation.com.au/commercial-and-industrial-insulation/underslab/industrial-board-blanket/supertel which they have in stock and sell for $230 for 2 pack of 3 x 1.5m (100mm thick). I have no idea about the performance of this product and I was wondering if anyone could shed some light as to whether it will be similar in performance to the Polymax (particularly in the low end obviously). Thanks in advance for any help!

Item: Martini absorb XHD100 and HD100 Location: Melbourne, Burwood East Price: $250 per XHD pack and $180 per HD pack Item Condition: brand new in packaging Reason for selling: NLR Payment Method: Pickup - Cash Extra Info: part of my hallway clearance sale!, pickup only Purchased too many packs and so have one pack of XHD100 and one pack of HD100 both in black. Each pack has 3 pieces, each piece is 2400mm high x 1200mm wide x 100mm thick. The XHD is quite rigid and will easily stand by itself. The HD will stand well enough if leaning against the wall. These work well as broadband acoustic absorbers and are fairly easy to cut. The beige coloured absorbers in the photo are also for sale in a separate ad. Pictures:

Item: Polymax Absorb XHD batts 100 mm thick, white (well light grey actually) Three pieces 120 cm x 73 cm Three pieces 95 cm x 73 cm One each 120 cm x 64 cm, 120 cm x 19 cm, 115 cm x 19 cm Location: VIC 3212 Price: $180 the lot Item Condition: Used, cut to size, otherwise great, Reason for selling: Baby! Need the space Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: Local pick-up preferred, could arrange drop-off around Geelong or Melbourne western suburbs. Would sell separately, in a pinch. However, you'll be better of buying the lot so you can to this (will throw in the mdf strips if you require): Pictures:

Item: Polymax XHD Black Acoustic treatment panels Dimensions: Full sheets 1200mm W x 2400mm H x 50mm Thickness Price: $119 ea (1-5 sheets), $99 ea (6-11 sheets), $89 ea (12 sheets) Cut to size: $39 ea (600x1200) or $49 ea (800x1200) or custom sizes by request (quote required) Location: Pick up from Seaford, VIC (outside business hours pick up available). At this stage we only offer local pickup. Polymax Absorb XHD are popular for DIY acoustic treatment panels. These are a black high density polyester panel ideal for acoustic absorbers or bass traps. Although not intended to be used as a finished panel without some kind of covering, many will find the raw panels look "good enough" without adding fabric. By request we can cut them to custom sizes.

Item: Polymax Absorb XHD batts 50 mm and 100 mm, white (well light grey) 50 mm: two full sheets 1200 by 2400 mm, one offcut 900 x 1700 100 mm: one offcut 1200 x 1700 Location: VIC 3212 Price: Full 50 mm sheets $50 $45 each, 100 mm offcut $50 $45, 50 mm offcut $25 $20 Item Condition: Unused, stored in the protective bag it was delivered in Reason for selling: Surplus to my needs Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: Would sell separately Bought full packs for acoustic treatment, these are the leftovers. Prefer pickup, but can arrange delivery within ~50 km from 3212. Pictures: t