DavidH71

I will get some finished photos. The subwoofer is one i stumbled across on the net about 20 years ago , Pro PA driver JBL2226 , sand filled walls , weighs about 160KG , some build photo's attached. I built one back then and have only just recently built another one. Link for my sub. http://mainkas.tripod.com/page/audio/allmighty/tangen_sub2r.htm MSO is Multi Subwoofer Optimiser , it is for use when you have more than one subwoofer and more than one seating position to optimise for. You take measurements with REW at the different listening positions of each sub then the main speakers. Then import these measurements into MSO and set some parameters. It will try to give the flattest output for the subs taking room modes into account and blend your subs with your main speakers. The end result for me was i no longer had the strong resonant frequencies in the bass from the room modes , nice even bass. I have been used to the sound with the strong modes so initially it felt like it removed a lot of bass but it is actually more accurate now and all bass frequencies are the same level. MSO link. https://www.andyc.diy-audio-engineering.org/mso/html/index.html Cheers

I spent the weekend setting up my two subwoofers with MSO software ( Multi Subwoofer Optimizer ) and what a difference. I now have clean tight non resonant bass where as before there were definitely quite noticeable resonate peaks which muddied the sound. Dual subs and MSO are definitely worth it. They blend very well with the SBA-761 speakers crossed at 60HZ Cheers

I spent a couple of hours last night listening to the them and i couldn't help myself and say something. In one word "WOW". The bass is awesome , you could quite happily go without a subwoofer , it produces every note except the very very bottom registers , i am totally blown away , sat there with a big stupid grin on my face probably for those 2 hours. It is exactly what i wanted as i need strong bass to keep up with my subwoofers , always felt my old speakers struggled in this regard , i haven't tried it with the subs yet as i was enjoying the sound i was hearing too much , but i am confident it will be awesome. I kinda see what Troel's means when he mentioned they sound different , they do but in a good way. The midrange is very strong but not harsh or overpowering , it puts vocals right in front of you and sound very crisp , clean and smooth. Top end is also very clean and i have the sparkle i wanted with no harshness. But for me the most impressive thing is the bass quantity and quality , i am a bass head. I mostly listen to electronic/Drum & Bass. So i am over the moon with the end result and they will only get better with time. Happy Dave 😀😀😀

No worries Brian, I know you are only trying to be helpful. All tips/suggestions are welcome. Hopefully i will be able to give my opinion on the sound in a week or too , i'm not going to rush to judgment this time. Thanks

I am confident the wiring is correct , REW would have shown a dip around the crossover frequency if the tweeter was reversed and i double checked. I struggle to justify the expensive caps for the supposed small improvement , i'm in the electronics industry and those caps just seem ridiculously expensive to me , thanks for the suggestions anyway. Yes the small cap and resistor is to attenuate the 5-10Khz region of the MW19 as Troels said he didn't like it without it. I had a busy weekend and have finished the second one except i ran out of the covering and only have covered the front and back so i could install the drivers , port and speaker terminals , it was late last night so haven't had a chance to listening to them , but i will when i get home from work today. Cheers

Jesus , how many of us have been approached by these scammers. I have 3 times over the last 30 years , and one time they were cruising the shopping center where i have lunch every day and i recognized them and shouted out to them so everyone could hear , that they were scammers , of course i got a torrent of abuse back and we ended in a shouting match. At least they didn't scam anybody in that car park that day.

Thanks BioBrian Last night i changed the tweeter resistor to bring the level up a bit and that has had quite a dramatic improvement. Also i think it is slowly improving or i'm getting more used to the sound. Your right about stereo , i came to the same conclusion last night after thinking about it more , i need both going before judging them. Up until last night i was just listening to it alone , i turned the subs on and actually the balance is very good. When i first built the ultimate subwoofer 15 years ago i was a bit disappointed but soon realised it was because i had only heard distorted bass before then and it took a little while to fully appreciate its performance , i think a bit of that is going on here too. So before i give any more info on sound quality i'll wait until it's all been together for a week or so. Anyway , i'm much happier now. Cheers David

Now i have spent a bit more time with the one speaker i am very disappointed. My previous comments were only after about 15 minutes of first playing music through them and i think i was a bit biased as i just built them . The strong bass is actually one note bass (70hz , confirmed with REW measurements). I have since blocked the bottom cabinet port and it has improved it a little bit , but still far from what i was expecting. The sound just doesn't excite me and i find it very hollow , the vocals just don't have any meat to them , kinda echoe. No sparkle , but i can bring the tweeter level up a bit by changing a resistor in the crossover and that should help a little. It's weird the longer i listen the less i want to. I know i'm judging by just one speaker and i hope things improve a lot when i have 2 running. Not what i was expecting at all especially after reading numerous positive reviews of the Satori drivers and my own experience with SB drivers My car setup sounds way better although that's an active setup. Also i think they are a bit tall , i have had to angle them down a bit for my seating position. I am still hoping they need to loosen up more (have been playing music every night since i set it up and also about 4 hours of 10 - 15hz near xmax) I have gone over all my calculations for box volumes and i'm about 0.3 litre bigger than his spec and the bottom port is not as wide which means it is tuned about 1hz less , and my cabinet is 15mm longer at the bottom , i don't believe this is it. I have used different crossover components , the 1.2mH and the 0.33mH inductors have slightly less DCR than his and i have the dayton caps not his expensive AlumenZ caps The REW measurement doesn't show anything bad (except the 70hz hump) , from 500hz up it is a very smooth line , very closely matching his frequency response graph , below 500hz my room modes takes over and it's a bit lumpy. My Dats impedance sweep matches his as well. I have excactly the same cabinet damping as his but i will experiment with removing some. So i am a bit lost on where to go from here to fix/improve it. At this point i'm a bit bummed and in no hurry to finish the other one (i will). David

Thanks mikk, It actually looks better in person , the photos don't do it justice. I thought i better mention the sticky back plastic i used was very easy to apply. I used their recommended tool( a piece of hard plastic with felt on on one edge). I only had 1 bubble and that was very easily rectified (lifted back up and re-apply) , probably took me about 30 minutes to cover the one speaker. I wasn't sure what i was in for as had never used it before but it was ridiculously easy to apply. I'm about halfway through the other cabinet , i won't be rushing , the glueing process slows things down quite a bit , i like to allow at least 6 hours (preferably 24hrs) before i unclamp and move on , in saying that i might have it finished this weekend or early next week. Oh and one other thing i only discovered after mounting the drivers was that i need to blacken the MDF behind the drivers as on certain angles you can just see the yellowish MDF , which on a dark cabinet stands out. Cheers David

One down ,One to go. I'm pretty happy with how it turned out , look like high end speakers. Of course i couldn't help myself and i'm listening to it now and although only one and not loosened up yet ,it sounds pretty damn impressive , very solid in the bottom end and vocals sound like there in the room with you , very clear. Can't wait to get the other one finished and get the full stereo sound. I'll give another report once i have both speakers done. Cheers David

I have managed to fix the tweeter face cut out being to big by carefully routing a 1.5mm ring from 6mm MDF . I made the ring slightly larger than i needed then cut little pieces out of it until it fit perfectly in the circle cut out then glued it in place. I ended up with about 1mm left protruding upwards and just sanded it flush. Tweeter is nice and snug now with no gap , i'm happy. Cheers David

Argh , i have to make the front baffle's again as i miscalculated , there is supposed to be 115mm from the top of the cabinet to the baffle that has the MW16 and MW19 mounted to it , i currently have 120mm. Oh well at least i discovered this before i glued it on to the cabinet and only have to remake the front baffle's , i just picked up some 4mm ply and have plenty of 16mm MDf to make up the 20mm thickness. The first cabinet now has the crossover mounted , wiring routed and the 8mm felt glued to the panels , next step was to glue on the baffle. I have started the second cabinet. I now have the MW19 drivers , obviously it will be a bit longer before i have them finished , i hope to get a lot done over easter. David

I have some pictures for the SBA-761 i'm building in the DIY section.

I have SB Acoustic drivers (SB17MFC35-4 , SB29RDNC-C000-4) in my car and they sound fantastic , this was my first time with SB Acoustics and i was very impressed. The SB17MFC have amazing tight clean bass and can be cranked very hard , (150w rms amps) with no change in sound , blows me away every time i really crank it. So i wanted to use them for home and began looking for diy speakers using SB acoustics drivers. When i found the SBA-761 on Troels site (http://www.troelsgravesen.dk/SBA-761.htm) , it matched what i was looking for and had the crossover values so decided to build them. I have done most of one cabinet and will begin the next one shortly. He uses 20mm Birch Ply , i have used 25mm MDF and have made the cabinet deeper to compensate for the differences. The baffle for the MW16 and MW19 is 20mm (16mm + 4mm MDF) so as to keep the correct tweeter offset. I also knocked up a quick PCB for the crossover (i'm an electronics tech and it's part of my job designing PCB's), after building it i wanted some way of testing it so i used DATS V2 impedance sweep. Interesting thing i found when comparing the 2 crossovers was i had a small difference in the dc resistance from one to the other. After some more investigating and resoldering one of the coil wires it was due to a small amount of enamel coating still left which didn't allow the solder to fully flow around the wire. Visually it looked good , so i am glad i tested them as now they measure identically. I have everything except the 2 x MW19P-8 drivers , i will be purchasing them in the next month or so through WES Components , i have an account through work. I couldn't make up my mind as how to finish them but i have ended up buying some of this https://crockerspaint.com/eshop/Natural-Stone-and-Tile-Self-Adhesive-Lining-Papers.html I liked the marble black , something different , i guess we'll see in a month or so. If it doesn't turn out ok i can peel it back off and go a different way. I am a bit annoyed at myself though as the tweeter face cut out is 1.5 mm to big , i have a Jasper router jig and because of where the router bolts to it the pin hole i needed was hidden so i was lowering it down onto the pin and was 1 hole out , doh , normally i do it the other way , insert the pin into the jig first. Now i am trying to figure out how to make up the gap , i do have a 3d printer and could print a ring that would fit perfectly. I will update as i progress through the build. Cheers David Crossovers: Solen Inductors 14awg Dayton Audio Caps ( i can't justify the expensive caps) Low inductance resistors. No ground plane on the PCB.

Further information: Photos: Advertisements without photos of the actual item will not be approved. Hi, I have 2 x Brand new never used Alpine RSB-W12D4 Subwoofers , unused project. https://www.alpine.com.au/shop/subwoofers/type-r-subwoofers-subwoofers/rsb-w12d4/ Need money for the next project. Price is for the pair. David