Guest Posted February 11, 2016 Posted February 11, 2016 (edited) @@davewantsmoore OMG Dave posted a photo ! Looks cool Dave, what does music sound like coming from it ? . Also of note is that it looks like a great place for a pet to hide from a child, which will be coming about soon I guess. Regards Edited February 11, 2016 by Guest
Guest Posted February 11, 2016 Posted February 11, 2016 So close yet so far. Many little jobs to complete, but trying to ditch the perfectionist attitude ...... Right now, mostly just having fun annoying the neighbours. Very short sounds (ie. ones which cover a very wide bandwidth of frequencies), like tuned percussion, door slamming, window smashing, etc ..... just sound so real, it is amazing. msg-108814-0-23306400-1454933927.jpg Back chamber - Size reduction? + stuffing or lining Cone reinforcement? - I don't mind if the mass goes up a little Wiring for the driver - I think I might just wire direct from the driver to the amp without terminals etc... it will be about a 3m run through the wall to the room where the electronics are. Panel damping top - Currently use temporarily 1cm rigid cardboard, and another 3/4" plywood - need something more permanent. I was thinking rubber or carpet, will need to experiment. Also a minor worry is vibration transferring into the horn which will sit on top - but I am hatching a plan to hang them from the ceiling ('dr evil' laugh) Panel damping sides - fix on some wood+metal stiffners running down the sides (on the outside, so once it's in the corner they don't be visible) I really though I was going to need to make it thicker in places - but simple damping is giving excellent results. ... and then on to some outdoor measurements, before the weather turns.... beautiful warm and calm days here right now. Perfect for speakr measuring. Panel Damping Top Saw at Bunnings a shredded rubber mat type thing. They come in solid and mixed colour, red/black/black/green the usual. Normal application is outside play zone for toddlers and for over decks. They are about $40 ?each and are around 1500 x 1500mm x 10mm thick and quite heavy. May do your job. May also work for damping and reducing internal chamber volume. Permanent wiring is Ok if you intend never to move it Weather cannot stay like this for long, enjoy ! Cheers
davewantsmoore Posted February 11, 2016 Posted February 11, 2016 Looks cool Dave, what does music sound like coming from it ? The biggest difference I notice is the pitch is -incredibly- well defined. When playing drum tracks you can hear exactly which drums were used, and how tuned, etc. Really needs a subwoofer though.
davewantsmoore Posted February 11, 2016 Posted February 11, 2016 (edited) Panel Damping Top Saw at Bunnings a shredded rubber mat type thing. They come in solid and mixed colour, red/black/black/green the usual. Normal application is outside play zone for toddlers and for over decks. They are about $40 ?each and are around 1500 x 1500mm x 10mm thick and quite heavy. May do your job. May also work for damping and reducing internal chamber volume. Ooo. Thanks. I'll check it out. I've got a bunch of different rubber and tiles from there over the years to experiment with ... but nothing anywhere near that big. (I need 1.2m square) ... and that is dirt cheap compared to what else I've seen Edited February 11, 2016 by davewantsmoore
Guest Posted February 11, 2016 Posted February 11, 2016 (edited) @@davewantsmoore, there is a literal container load they are moving in Burnie at the moment, yea, cheap as chips. I was trying to make up a use for them also, because of the price. If none down south I will drop by, take a photo and post, can certainly grab a couple, no prob. Size was a memory guess, but easy 1200mm square, not smaller. Possibility to line out my 400 liter enclosures, polyurethane glue the panels into the box cut to size. Sadly I live about 1000m from the new Burnie Store Edited February 11, 2016 by Guest
acg Posted February 11, 2016 Posted February 11, 2016 (edited) Back chamber - Size reduction? + stuffing or lining Dave, are you considering 'tuning' the backchamber by ear? I will be doing that for my Upperbass Horns (100Hz - 600Hz) and would be most interested in your efforts should you decide to proceed that way. EDIT: MDF rings of soft forming expanding foam is what I will use to stuff the backchamber...you can then carve out the foam with a knife to the desired shape/size. Edited February 11, 2016 by acg
acg Posted February 11, 2016 Posted February 11, 2016 Panel damping top - Currently use temporarily 1cm rigid cardboard, and another 3/4" plywood - need something more permanent. I was thinking rubber or carpet, will need to experiment. Also a minor worry is vibration transferring into the horn which will sit on top - but I am hatching a plan to hang them from the ceiling ('dr evil' laugh) Well, I would recommend a 'soft' weight to damp those resonances, like sand bags, but obviously something more pretty than that. Maybe build on a second skin with a void between that you can fill with a homogeneous material. I have my accelerometer and pre-amplifier built up here...that would be an excellent tool to measure success in the resonance reduction department...could perhaps send it down to you if you wanted to be a guinea pig for ironing out the wrinkles of its initial deployment and establishing a protocol for its use.
davewantsmoore Posted February 11, 2016 Posted February 11, 2016 Dave, are you considering 'tuning' the backchamber by ear? No. I would actively discourage that, for a few different reasons. I'll look at the electrical impedance curve. Maybe build on a second skin with a void between that you can fill with a homogeneous material. Yes, something like this. Right now, I am using a large piece of 1.5cm thick rigid cardboard, and another 3/4" plywood on top... and this makes a really quite substantial difference. I have some soft rubber or carpet that I will try. I'd like to use "something" then another sheet of ply on top, to keep the look.
Guest Posted February 12, 2016 Posted February 12, 2016 A tiny little project to make up a power supply for the well traveled trans Bass Straight twice Retrothermonic "La Gitana" valve phono stage (less than 1A @24vac) preferring to do this rather than every time when looking at the power board a freeking Jaycar sticker on a yucky wall wart, farrrrk NO ! This one has a nice Aluminium box for a little extra shielding, an IEC filter/fuse/switch socket and some more blingy plugs and sockets. Interestingly the whole power supply circuit has 2 fully isolated transformers before the juice gets into Mark's massive filter circuit. TBC......should take an hour Then "if" it goes I'll leave it warm up another 2 hours then it can make beautiful music. I hope, this time around
mwhouston Posted February 12, 2016 Posted February 12, 2016 (edited) I see you have a Jaycar power tranni there - lol. So how goes it? Edited February 12, 2016 by mwhouston
Guest Posted February 12, 2016 Posted February 12, 2016 It's a Soanar Tranny same as the one in the pre (matched pair), was purchased at *****r The box will have my label on it will happen some time this evening, have a Family Day
A J Posted February 13, 2016 Posted February 13, 2016 A new phono stage - Salas Simplistic Folded Phono. Only taken me about 2-3 years to finally put it together. Custom wound transformers from Harbuchs. It's a little messy as its in testing stage now. Came up pretty well on first fire up. Brothers in arms has been on high rotation. I plan on moving it into two separate boxes - psu in one and phono stages in another. It's actually reasonably quiet in its current form and sounds downright stunning. Sent from my iPhone using Tapatalk 4
betocool Posted February 13, 2016 Posted February 13, 2016 A new phono stage - Salas Simplistic Folded Phono. Only taken me about 2-3 years to finally put it together. Custom wound transformers from Harbuchs. It's a little messy as its in testing stage now. Came up pretty well on first fire up. Brothers in arms has been on high rotation. I plan on moving it into two separate boxes - psu in one and phono stages in another. It's actually reasonably quiet in its current form and sounds downright stunning. Sent from my iPhone using Tapatalk Very nice, very nice indeed!
A J Posted February 13, 2016 Posted February 13, 2016 It seems to plumb depths of bass I haven't heard before on a phono - This album is a real stunner on this Sent from my iPhone using Tapatalk 1
mwhouston Posted February 13, 2016 Posted February 13, 2016 (edited) I would never have raw timber speakers in the house, I think it crass. But I have waited months, and months and months to get babies up and running so I have allowed myself a few days with the boxes like this. The drivers are Spanish Beyma - 15" concentric drivers with a 2" titanium and Mylar inner tweeter. They 99db efficient and will handle up to 700W of music. These will be painted black with the much talked about "Houston finish". My amp building buddy Don made the raw boxes for me. With baffle board off we added vertical bracing, bituamised heavy Al foil and Dacron and open box bracing in the lower 1/4. The ports at the back are two 14.5" diameter and 8cm long double thickness plastic pipe. The bass sound good but Beymas take about 100+ hours to even slightly loosen up. They should go to 40hz. My 2.6W EL84 "Tamarisk" amp is driving them loud and clear. Images to follow. Edited February 13, 2016 by mwhouston 1
mwhouston Posted February 13, 2016 Posted February 13, 2016 @A J, impressive. Jaycar 2U 19" rack mount. They have a nice stipples finish on them these days.
A J Posted February 13, 2016 Posted February 13, 2016 @A J, impressive. Jaycar 2U 19" rack mount. They have a nice stipples finish on them these days.Yeah - I've got a bloody rack of them now - two are amps and this phono. For $100 they are ok for projects like this. I seem to recall spending about 2k on a Dac from the Gold Coast which also used these boxes. Sent from my iPhone using Tapatalk 2
Guest Posted February 13, 2016 Posted February 13, 2016 @A J, Nice work, well done, another winner Cheers.
Guest Posted February 13, 2016 Posted February 13, 2016 @@Dirty_vinylpusher Not much of a DIY unless you show the guts of it
Guest Posted February 13, 2016 Posted February 13, 2016 (edited) Put the little 24v ac supply together, all fused with a 0.2A on the primary side and a 1A Forgot to get my multi meter from work so I plugged it in anyway to the pre amp and fire in the hole. I am assuming @@mwhouston that the tiny red glow from the "part" between the copper err, thingies at the top of the valves means it is going dunno EDIT and the LED on the front, ah , will plug it into the system shortly after the lids are on, see if it actually makes a noise. Edited February 13, 2016 by Guest
Guest Posted February 13, 2016 Posted February 13, 2016 @@Dirty_vinylpusher Not much of a DIY unless you show the guts of it That's all you're getting for now
mwhouston Posted February 13, 2016 Posted February 13, 2016 @@125dBmonster, yes faint red glow at the top of the valves and faint yellow glow from the front led. Your killing me.
Guest Posted February 13, 2016 Posted February 13, 2016 (edited) Well @@mwhouston Retrothermonic "La Gitana" is a success give it a few hours to warm up now, listen to a few records and see how it goes. To be frank and straight up I didn't know what to expect, because of my habit of binning very expensive perfectly crappy valve amps. Straight up though, seems to cover the full bandwidth well and place a nice image, without any colouration, very cool, impressive. Surprised that some thing as sensitive like a phono pre, with valves is so quiet, with bugger all noise floor a very, very faint leak through of the dreaded hum. When I say very very faint and no hiss, I mean very faint, barely there just above the Monarchy Audio Pro Class A and the Holton Precision Audio on a 110dB per watt + super sensitive horn (no worse than the Mimic BTW) Nothing at all to worry about. Pull my head out of the horn now . Sounds Ok to me. You can relax Mark, all is well. Lovely work. now to enjoy my customary 6 pack to celebrate the completion of another DIY, in this case my shielded ac power supply and the successful integration of "La Gitana" to the horn rig. Edited February 13, 2016 by Guest
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