Congrat's on the first meeting, don't forget to let us all know how it goes and what happens.
Ted
Ted
To those in Melbourne, MAC (Melbourne Audio Club) is having a meeting tonight in the Waratah Room, City of Whitehorse Offices (Nunawading, off Maroondah Highway). It's a vinyl night, and as the original program fell through, it's going to be members' equipment only. Here for more details.
Put up with half an hour of meeting necessaries at the start and then we get to the music. Will probably end up going to 11 or later. Who knows, you may end up joining...
Put up with half an hour of meeting necessaries at the start and then we get to the music. Will probably end up going to 11 or later. Who knows, you may end up joining...
C'mon Sydney guys and environs,
I'm curious here and maybe others will have theories on this.
On the aussie forum, all the gtg's and socialising goes on in melb/vic. Regular as clockwork and at the drop of a hat. By contrast, very very little goes on in Syd/NSW, all attempts and efforts to organise something usually fail.
Why would this be I wonder? Maybe all the audio people live in Melb so pure density assures it?? Weather? Melbourne people are friendlier and more outgoing?? Interesting question.
Another example, the race weekend out here. We've had a few casualties in the numbers (work commitments change in the months since EOI's were lodged for example) but the point is, even though I'm in Bathurst only about 10% of the numbers coming are from NSW, the rest are from Melbourne!! Go figure.
Anyway, let us know how both the Bris and Melb happenings go. It does look like the regional events will happen first, which has always made more sense to me.
Ted, I did notice you put a 'heads up' in some of the sub-forums, doesn't look like they produces any results, interesting. Maybe this threads title should have included words along the lines of 'meets, GTG's, etc ', tho having said that it's pretty clear once you get in here what it's all about.
Just doing an edit so I can remember to UNTICK the e-mail box!! Does anyone know how to make it an 'opt-in' rather than an 'opt-out'???
I'm curious here and maybe others will have theories on this.
On the aussie forum, all the gtg's and socialising goes on in melb/vic. Regular as clockwork and at the drop of a hat. By contrast, very very little goes on in Syd/NSW, all attempts and efforts to organise something usually fail.
Why would this be I wonder? Maybe all the audio people live in Melb so pure density assures it?? Weather? Melbourne people are friendlier and more outgoing?? Interesting question.
Another example, the race weekend out here. We've had a few casualties in the numbers (work commitments change in the months since EOI's were lodged for example) but the point is, even though I'm in Bathurst only about 10% of the numbers coming are from NSW, the rest are from Melbourne!! Go figure.
Anyway, let us know how both the Bris and Melb happenings go. It does look like the regional events will happen first, which has always made more sense to me.
Ted, I did notice you put a 'heads up' in some of the sub-forums, doesn't look like they produces any results, interesting. Maybe this threads title should have included words along the lines of 'meets, GTG's, etc ', tho having said that it's pretty clear once you get in here what it's all about.
Just doing an edit so I can remember to UNTICK the e-mail box!! Does anyone know how to make it an 'opt-in' rather than an 'opt-out'???
terry j said:
Terry,
I know of the new Sydney Audio Club, which started up in July (I think). Davohorn58 posted the info in post #25 of this thread. These clubs need your patronage for the first couple of years (at least) to get off the ground. As it has been organised, and is up to its' second meeting (or third) it might be worthwhile to add your interest (monetary even if you can't get there in person).
That goes for all Sydney-siders, not just you...
Terry, mate I think it must hafe more to do with the huge mortgages and incredibly difficult traffic conditions, although we Mexican are renowned for our freindly attitude and our shallow pockets.
Ithe partner ans I only just finished work so the MAC meeting is out, I do have a preference for vinyl so sorry to miss it, and I must rejoin
Ithe partner ans I only just finished work so the MAC meeting is out, I do have a preference for vinyl so sorry to miss it, and I must rejoin
Re: Re: DIY speaker-builders meeting soon in Brisbane!!!
Numbers have now risen to 10.
We can cope with 2 more. First in, best dressed ...
Doug
Brisso57 said:
Numbers have now risen to 10.
We can cope with 2 more. First in, best dressed ...
Doug
G'day to all. I have been too busy designing, building, and working for the dollar to notice this thread. Sinful.
Please don't hold your breath, but I may still have the EA design for the Magnavox 8-30, and 8WR with the 3TC (?) tweeter. The Rola and Maggy 8 inchers should be fine on OB. These drivers should respond well to cone treatment. Consider helper on OB also. I have started on a new OB, with the option of going to a cab for the the bass below 100Hz. The box is not needed. The pic shows the response at present, with no bass compensation on the SPL meter.
The meet sounds like fun. Been back thru the thread, can't see where Phil's place is. I assume it's Brisbane.
Geoff
Please don't hold your breath, but I may still have the EA design for the Magnavox 8-30, and 8WR with the 3TC (?) tweeter. The Rola and Maggy 8 inchers should be fine on OB. These drivers should respond well to cone treatment. Consider helper on OB also. I have started on a new OB, with the option of going to a cab for the the bass below 100Hz. The box is not needed. The pic shows the response at present, with no bass compensation on the SPL meter.
The meet sounds like fun. Been back thru the thread, can't see where Phil's place is. I assume it's Brisbane.
Geoff
Attachments
OB 8" ROLA and Magnavox
Wish I could make it to the GTG, but long distances over short time are hard to achieve;-(
What do you think of this design for OB ROLA or Magnavox 8s?
http://www.visaton.com/en/bauvorschlaege/breitband/noboxbb/index.html
Do you know anyone who has built NoBox design? I already have a couple of slabs of 35mm hardwood (ex bedheads) about the right size for the front baffles. MDF or thick ply should be OK for the side panels.
Ozziozzi
Wish I could make it to the GTG, but long distances over short time are hard to achieve;-(
What do you think of this design for OB ROLA or Magnavox 8s?
http://www.visaton.com/en/bauvorschlaege/breitband/noboxbb/index.html
Do you know anyone who has built NoBox design? I already have a couple of slabs of 35mm hardwood (ex bedheads) about the right size for the front baffles. MDF or thick ply should be OK for the side panels.
Ozziozzi
Hi Ozziozzi,
I used to do the long distances over short times. Fines take the fun out of it.
The 6 and 8" Rolas should be fine on OB. I know the 12" dual cone ones are good on a 5 x 3 foot baffle. The main drivers on my current project are Panasonics from the 70's, with cone and surround treatment, and extra magnet. For best top end, a curvilinear cone is better, preferably without a whizzer. I'll post details at a later date.
IIRC, the Rolas have a straight ribbed cone, the Magnavox were curvilinear, as were MSPs.
The Visaton baffle will be fine, however, the B200 is a great driver, don't expect that performance from a Magnavox. Great if you do get it though.
My baffles are 900 mm high. The bass is much better than expected.
I used to do the long distances over short times. Fines take the fun out of it.
The 6 and 8" Rolas should be fine on OB. I know the 12" dual cone ones are good on a 5 x 3 foot baffle. The main drivers on my current project are Panasonics from the 70's, with cone and surround treatment, and extra magnet. For best top end, a curvilinear cone is better, preferably without a whizzer. I'll post details at a later date.
IIRC, the Rolas have a straight ribbed cone, the Magnavox were curvilinear, as were MSPs.
The Visaton baffle will be fine, however, the B200 is a great driver, don't expect that performance from a Magnavox. Great if you do get it though.
My baffles are 900 mm high. The bass is much better than expected.
Attachments
Hi Geoff, I am up on cone treatments (Damar, C37, diluted Aquadhere, puzzlecoat etc), but what do you use on the surrounds? I have considered water-based contact cement which dries to a thin rubbery coating that looks very much like that on Magnavox surround.
Did I read you right that you suggest removing whizzer cones on speakers? If I use a good supertweeter whizzers are probably not necessary.
When you mention baffle size do you include the side panel dimensions?
And what is that oval bass driver and where did ya get it?
Ozziozzi
Did I read you right that you suggest removing whizzer cones on speakers? If I use a good supertweeter whizzers are probably not necessary.
When you mention baffle size do you include the side panel dimensions?
And what is that oval bass driver and where did ya get it?
Ozziozzi
" Did I read you right that you suggest removing whizzer cones on speakers? If I use a good supertweeter whizzers are probably not necessary."
Careful now! No, I am suggesting a single cone is better than a dual cone. I have removed the whizzers on other drivers, hoping to extend the top end of the main cone. No success there yet. Not like the results on the 6" Panosonics.
For further info see:
http://www.diyaudio.com/forums/showthread.php?postid=1282395#post1282395
It doesn't seem possible for me to make it to the GTG. A pity, because I need some unbiased opinions on my current project, and comparisons with others.
Geoff.
Careful now! No, I am suggesting a single cone is better than a dual cone. I have removed the whizzers on other drivers, hoping to extend the top end of the main cone. No success there yet. Not like the results on the 6" Panosonics.
For further info see:
http://www.diyaudio.com/forums/showthread.php?postid=1282395#post1282395
It doesn't seem possible for me to make it to the GTG. A pity, because I need some unbiased opinions on my current project, and comparisons with others.
Geoff.
Just remembered some other info. The slim aperiodic box may have been the Playmaster Slimline, from EA or R,TV&H. The 8" Magnavox, is that the 8-30? 30 watts (music) 45Hz 91dB/w/m. You sometimes see them on eBay.
Stop it you guys, I can smell dust burning on the 6BQ5s.
Geoff.
Stop it you guys, I can smell dust burning on the 6BQ5s.
Geoff.
Vintage oval bass driver??
check these on Epaynz,
http://cgi.ebay.com.au/Vintage-Oval...ryZ18800QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
they look sort of familiar don't they, might be worth $5-
I am still chasing another pair of b139's but only if the price is right,
check these on Epaynz,
http://cgi.ebay.com.au/Vintage-Oval...ryZ18800QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
they look sort of familiar don't they, might be worth $5-
I am still chasing another pair of b139's but only if the price is right,
Magnavox 8-30, 8WR and 8PX.
Geoff, the 8-30 I have is the one with the VERY solid cast frame (aluminium or could be some other alloy) painted gloss enamel mid-grey colour. It also has big magnet with red plastic cover and *slightly* curvilinear cone--ie not quite flat with an accordian surround treated with what looks like a "spatter-pattern" of a rubbery substance. Other marking is "747". The Magnavox 8WRs and 8PXs have a pretty flimsy punched and pressed 4-spoke metal frame that rings like a bell!!! Both definitely need treatment if they are to be used as a FR driver.
The ROLA/Playmaster "Slimline" enclosure you mention could be the one I built. Sounds familiar. Have you found your old EA or RTV&H plans? I would certainly like to see some of those as a basis for experiments.
Re: GTGs I am interested in running gtg in Canberra, but I want to find a suitable venue & accommodation before I commit further. An interesting alternative is Goulburn which is halfway between Canberra and Sydney so about an hours drive from both-are you reading this ZeroOne in Goulburn ;-) I will PM ZeroOne and see if he has any suggestions.
Cheers
Ozziozzi
Geoff, the 8-30 I have is the one with the VERY solid cast frame (aluminium or could be some other alloy) painted gloss enamel mid-grey colour. It also has big magnet with red plastic cover and *slightly* curvilinear cone--ie not quite flat with an accordian surround treated with what looks like a "spatter-pattern" of a rubbery substance. Other marking is "747". The Magnavox 8WRs and 8PXs have a pretty flimsy punched and pressed 4-spoke metal frame that rings like a bell!!! Both definitely need treatment if they are to be used as a FR driver.
The ROLA/Playmaster "Slimline" enclosure you mention could be the one I built. Sounds familiar. Have you found your old EA or RTV&H plans? I would certainly like to see some of those as a basis for experiments.
Re: GTGs I am interested in running gtg in Canberra, but I want to find a suitable venue & accommodation before I commit further. An interesting alternative is Goulburn which is halfway between Canberra and Sydney so about an hours drive from both-are you reading this ZeroOne in Goulburn ;-) I will PM ZeroOne and see if he has any suggestions.
Cheers
Ozziozzi
Hi Ozziozzi, most pressed frames will ring when held by the magnet, holding by the frame, the ring is reduced to a metallic thud. No one up here has duct seal, so I'm looking for an alternative.
The old mags are in the packing shed I think. With all this rain, I probably won't get into that before the weekend.
Geoff.
The old mags are in the packing shed I think. With all this rain, I probably won't get into that before the weekend.
Geoff.
rabbitz said:
You might be able to find a cheaper "clone" of Blu-Tack at Crazy Clark's or some other dollar discount stores.
Doug
I used 'Power Tack" which comes in a yellow packet, It might be Marbig brand. $1.99 a pack from the supermarket, firmer than blu tack and hard work to knead but you don't need to, just cut it to size with the wife's best dressmaking scissors and stick the flat pieces on. It is packed in a single sheet in the pack instead of 4 or 5 strips. About 2 packs per driver.
Jaycar sells foil backed bitumen sheets, 2 square feet for about $20. it goes a long way. Driver bakets are now duller than test cricket. 🙂
Jaycar sells foil backed bitumen sheets, 2 square feet for about $20. it goes a long way. Driver bakets are now duller than test cricket. 🙂
Attachments
OzMikeH said:
Jaycar also sell "speaker sealant" which might also work quite well. It also does the job it's intended for!?!
Geoff, you are right about holding speaker by mounting flange. This does naturally dampen the whole basket, but what the heck--damp the basket anyway right? It can't do any harm. One thing that hasn't been mentioned in this thread is to wrap the speaker magnet in felt.
I would careful of "Bluetac" and its mate "Yellowtac". I have found that Bluetac dries out slowly by losing its oily solvent and becomes slightly brittle and then falls off. it takes a while, but it does happen.
There is a another white tacker called Postertac from the same company (Selleys I think) who advertise that it "Does not leave oily residue on valuable posters or artwork--perfect for light coloured walls, does not dry up etc" or words to that effect. I suspect THAT might be better. Of course there is always Plasticene modelling clay (from toyshops) or its modern equivalent which is edible and non-toxic for babys sake ;-)
I bought a paint on body deadener from Supercheap (or Autobarn) called Brush On Sound Deadener. MOTOSPRAY brand. This is a bitumenlike goop loaded with a heavy barium mineral. A litre of it weighs about 2Kg. It dries to a slightly tacky surface that might also be useful for attaching some other treatment. A few coats is supposed to stop car body panels vibrating. Only problem is the solvent needs to evaporate before you seal up the boxes. It smells a bit like turpentine for 24 hours.
One other sound treatment I have used succesfully is rubber computer mousemats. These are made of black closed-cell, high-density foam with a smooth mousing surface on one side and a rough texture on the other. They vary from 2-3mm up to 8mm+ thick. These are usually thrown away because optical mice don't need them. I have cut them up for speaker mounting gaskets, enclosure wall linings and into strips for speaker frame damping.
HTH
Ozziozzi
I would careful of "Bluetac" and its mate "Yellowtac". I have found that Bluetac dries out slowly by losing its oily solvent and becomes slightly brittle and then falls off. it takes a while, but it does happen.
There is a another white tacker called Postertac from the same company (Selleys I think) who advertise that it "Does not leave oily residue on valuable posters or artwork--perfect for light coloured walls, does not dry up etc" or words to that effect. I suspect THAT might be better. Of course there is always Plasticene modelling clay (from toyshops) or its modern equivalent which is edible and non-toxic for babys sake ;-)
I bought a paint on body deadener from Supercheap (or Autobarn) called Brush On Sound Deadener. MOTOSPRAY brand. This is a bitumenlike goop loaded with a heavy barium mineral. A litre of it weighs about 2Kg. It dries to a slightly tacky surface that might also be useful for attaching some other treatment. A few coats is supposed to stop car body panels vibrating. Only problem is the solvent needs to evaporate before you seal up the boxes. It smells a bit like turpentine for 24 hours.
One other sound treatment I have used succesfully is rubber computer mousemats. These are made of black closed-cell, high-density foam with a smooth mousing surface on one side and a rough texture on the other. They vary from 2-3mm up to 8mm+ thick. These are usually thrown away because optical mice don't need them. I have cut them up for speaker mounting gaskets, enclosure wall linings and into strips for speaker frame damping.
HTH
Ozziozzi
- Status
- Not open for further replies.