| inrank |
was bored this morning, found some old full-range drivers from some car speakers (PYE i think) and put them in some OB's (of an old chest of draws).
WOW, they sound great, cant play that loud but apart from a slight hiss in the background they sound very musical and fun!
i think i will definatley go OB for a cost saving option, mabye look into the pioneer B20, although that needs a tweeter, any other full-rangers that are relatively cheap.
the B20's are from parts express, any idea how much shipping would be for a pair to the UK? |
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| inrank |
would cost me £65.60 for 2xB20's and 2xPiezo tweeters inc delivery to the UK, would i have to pay import taxes?
would cost £91 just for the B20 drivers from my nearest dealer in europe (excluding delivery) :eek: |
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| Vikash |
Hi, yup you'll pay 11% import tax IIRC plus 17.5% VAT, and an additional £13.50 if you have the misfortune of Parcelforce dealing with internal postage (i.e. sent by USPS).
From within the EU, you shouldn't be paying any of the above (VAT aside).
Did you end up trying the FR125s' in OB before you sold them? |
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| inrank |
no i didnt try them in OB, wish i had now, even for a play, oh well, want somthing that is a bit more sensitive though...
including both the taxes and even parcelforce, it would turn out just under £100 for the 2xB20's and 2xPeizo's!
looks like it will be cheaper than getting them from europe (Spectrum Audio).
if i did get them, could i point the peizo up or backwards on the OB?
on a difffernt point, these quick Ob's that i have made, they dont actually suffer from a total lack of bass, i have dound that it just works somehow :xeye: |
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| Vikash |
| quote: | Originally posted by inrank
including both the taxes and even parcelforce, it would turn out just under £100 for the 2xB20's and 2xPeizo's!
looks like it will be cheaper than getting them from europe (Spectrum Audio). |
With the dollar week against the pound atm, there's even more reason to buy from the U.S instead of Europe. I bought some Seas Millenium tweeters from Zalytron in the U.S and including all the tax hits and Parcelforce thievery, I still made a saving of about £60 over buying from Wilmslow Audio - more thieving &£^$&"*$.
Plus, there's always the chance they could skip your parcel at customs and you won't have to pay anything on it. It's happened a few time to me on packages in excess of £100 (albeit from Canada). |
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| inrank |
| just thinking that would i ever want more than the one B20 in the OB, (one would have to be rolled off) as they are so cheap (£12 each :eek: ) and would be cheaper to get them all in one.... |
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| lovechild |
Hi
you may want to look at the Monacor SP-200MX/8
or the Beyma 8AG/N.
both are available in EU, relatively cheap and known to work very well in OB
best, LC |
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| inrank |
yeah, looked at those, put off by the 1mm of xmax on the monacor, the beyma one looks better, 2mm but with 96dB, although both dont have as low fs as the pioneer, anybody used any of these in OB?
although with the higher fs, they should go louder with less distortion (as a general rule?)? |
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| lovechild |
Hi
but then the Pioneer has a low QTS, so it'll be hard to get much bass either way.
I don't know much about OB, but with Xbaffle you should be able to model the response.
Linkwitzlab should be a good resource to get some understanding of Dipol systems.
also, an xmax > 10mm is theoreticaly fine, but you will get hell of a distortion in the mid and upper frequencies when you run them fullrange - you might have noticed that from your FR125 when playing them loud.
LC |
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| inrank |
i dont know why i am fretting about bass really, aslong as i get some im fine, i have a sub so it isnt really that much of a problem.
from people's experience, which of these will be the best in OB then, what about the omnes audio L8 aswell?
http://www.spectrumaudio.de/breit/o...udioL8spec.html
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| Klimon |
Beyma 8AG/N might be a good alternative, it has high Qts and costs around 30E a piece here in Belgium. The sound is very good, notch filter at around 3k is optional, pierce or remove the dustcaps because it makes a difference with these.
Simon |
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| dmason |
I would head straight for the Omnes L8 Spec, the one done for Wolfgang at spectrum, designed, built, and tested for open baffle, AND with the all important phase plug. I have a feeling this is a good driver, and its FR plot is impressive as hell. Then you can follow along with the crowd on audiocircle as they invent the rules on state of the art bass emission. The Omnes appear to be highly sensitive as well. Addition Charlize, T amps are known to exert such driver control as to push bass response downward very noticably.
Omnes + Charlize, my vote. |
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| inrank |
yeah, on the spectrum audio website they have two, a normal L8 and an L8 'Spec' that is aparently modded for them (even though they are the same price (70 euro, about £50ish each), love the look of it to.
might get away without a seperate tweeter aswell.....
do you know where it has been tested in OB?
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| planet10 |
| quote: | Originally posted by lovechild
but then the Pioneer has a low QTS |
The pioneer doesn't have a low Qt in real life... typically up over 0.5
Did you check out the Ciares? I had a set of the B200s. Any number of even cheaper, used vintage drivers are better on an OB.
dave |
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| Zero One |
Inrank before you go and buy some more drivers, have some fun and just try a little mod or two on the ones you have there, they look very similar to a some 4 inch drivers I have used in a Double Bass system and the sound they produce modded is out of all proportion with what you might expect.
I use mine with a 10inch sub so bass is fine, but in the DB system using an active bass boost module they go down to 50hz or so.
Here what to try"
Paint the cone and whizzer with two coats of PVA both front and back.
Next cut 2 tissue paper circles (per speaker) that are large enough to cover the area where the cone joins the surround and then comes in about 1.5cm on the cone, then cut little slits radially in the paper and glue it to the cone with PVA, do the same with the second piece as well. (I don't mean to glue on the surround, just inside it)
Next take some small self adhesive compressed foam dots (the type that are used under ornanments to stop them scratching things) and stick them on the cone underneath the whizzer, but make sure they don't touch the whizzer.
Take another larger foam dot and stick it in the middle of the centre cap and then stick another two small ones on top of that. It sounds odd but trust me it really works.
Then take some non-slip rubber matting (the stuff that gets sild for putting in draws etc) and glue it to the frame outer surfaces and the magnet and around the area where the magnet joins the frame. ( I used double sided tape here instead of glue)
Finally get some virgin olive oil and brush it onto the surround , you may need a couple of coats.
Pop the speakers back onto your boards and have a listen, you may just find that this set-up in combination with the sub is a killer.
If you are able to get one of the sub boost kits from altronics in OZ (very cheap) it will sound way better still.
Give it a try, its cheap and easy! and enjoy DIY. |
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| inrank |
yeah will try that mod, i have found that even these in their small baffles sound bigger than any other of the speakers have had, and they have an ability to get my foot tapping aswell, not bad for 30min work with 50 pence worth of drivers!
will try that tommorow, got a pic of yours? |
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| inrank |
"Inrank before you go and buy some more drivers, have some fun and just try a little mod or two on the ones you have there, they look very similar to a some 4 inch drivers I have used in a Double Bass system and the sound they produce modded is out of all proportion with what you might expect."
simmilar except these are 3" units lol ;) (from side to side, 55mm cone and 32mm whizzer cone with an 11mm VC..... :D ) |
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| dmason |
Outstanding results!! Let the tweakage begin, looking forward to the results!
This will give you a baseline impression as to what you could expect down the road, when you step up to purpose built, killer drivers such as the Visatons, with the radiating area of an 8 incher. Beware: you may already have reached the point of no return.
Then add battery power and source, with its attendant no noise and rise time of lightning... |
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| Zero One |
Inrank I will take a pic and post it over the weekend, Id say you'd get results even with 3 inch drivers, with obviously less bass.
I did try mine on OBs, using single drivers per side, pairs per side and even triples in a triangular formation and an in line quad. Net result was the more drivers the more volume, huge with the 4 ups but the sound quality was no where near as good as a single! Basically more drivers kills the highs and distorts the upper mids.
I'm not sure about your drivers but mine are of the type that are used for PA works and in ceiling use, I think this may have something to do with why they work pretty well on OBs, afterall ceilings are just a very very big open baffle without the reflected sound coming back inot the room.
There are a lot of ceiling speakers available very cheap in sizes up to 8 inches that might have promise on OBs modded, heck I found some in town the other day, 5.5inches dual cone, and only $5.00 each. At that price if I totally stuffed them up it wouldn't matter. |
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| inrank |
yeah, am looking out for really cheap drivers, not many places around here except charity shops, car boot sales, ebay etc....
what about this using a Caire CH250 (10") driver
QTS 1.6
FS 57Hz
96dB
0.5mm xmax
4 ohm
£35 each
sounds promising....
or this one at Radio Spares....
which looks just like the Monacor SP-200MX and is only £12! |
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| planet10 |
| quote: | Originally posted by inrank
yeah, am looking out for really cheap drivers, not many places around here except charity shops, car boot sales, ebay etc.... |
If you know what to look for (or are just lucky) some awfully usful drivers can be found in some pretty poor to mediocre boxes -- particularily if you are doing an OB.
Too bad the teleporter is broen... i've got over a 100 candidate drivers....
| quote: | or this one at Radio Spares....
which looks just like the Monacor SP-200MX and is only £12! |
I've a series of mods that seem to wor pretty well on the low budget whizzer coned drivers (the 1st gunea pig were a set of blue & yellow drivers i got for <$20 that popped into the box my pioneer B20s were destined for. next gineau pig is a Fostec FE167.
dave |
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| Godzilla |
| re driver placement... should the driver in an OB be placed closer to the floor to minimize reflections off the floor? perhaps closer to the floor but angled upwards? |
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| Scottmoose |
| That's what the JE Labs (I believe) OB does. Me, I like larger baffles, but if spaced is restricted, this is probably as good a way as any to achieve it. |
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| 2litre |
I was wondering about that too.
Like if you have a high Qts driver placed at 30" vs one placed at say 12" off the floor.
I'm thinking that the one at 12" off the floor would display the 'high Q hump' more than the one at 30", yes?
Conversly, a driver of less Q may have its lower octave enhanced by being closer to the floor.
R/
Jim |
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| Zero One |
| Inrank, here is a pic of the modded and non modded 4 inch drivers, the modded one also has a phase plug made from the cut down cap of a glue tube nozzle, the Phase plug works really well making the highs smoother. These drivers sound brilliant in a double bass setup with sub, I have also used them on winged open baffles and the results were very nice. |
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| Zero One |
Inrank just for interest here is a similarly modded 6.5 inch driver, these also sound good, and I will probably use them on an open baffle. These cost just $5.00 OZ (about $3.20) US and including the mods owe me about $7.50 each. No specs but efficiency is pretty high and they reproduce the highs very nicely as well without a super tweeter.
I have other pics if you need more info.
The phase plug is actually the top of a black whiteboard marker, I go through heaps of these as I run a digital training business, so its a freeby. |
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| Kensai |
Has anyone tried just the Pio B20s with 25ohm inline resistor like Nelson Pass suggested? According to his tests, it looks like this would not only improve the bottom end noticeably, but would also extend its top end to remove the need for a supertweeter.
Actually, according to his article, the measurements he shows for the B20 are after taming the top end in the crossover, so possibly a more elegant solution in this case would be to mod the B20s with phase plugs. Sure, it would take alot more power to run this way, but seems like it would make a good match for common A/V receivers running around these days.
Anyway, the resistor would also significantly increase the B20's Qts which should make it an even better candidate for OB use.
I intend to (eventually) try this myself (don't anyone hold their breath), but I was wondering if anyone had tried either or both with the B20 yet.
Kensai |
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