Hoping to draw upon the experienced eyes and ears of DIY Audio members in identifying these unusual oval full-range drivers that I pulled from an 60s era "Kuba" 6GW8 tube based stereo-console.
Doesn't appear to be any rear-mounted motor structure so I'm guessing that the unusual flared rounded metal protrusions on the front and in the center of the cone are some form of motor.
They don't seem to exhibit any magnetic properties unconnected to the chassis so my guess is they become (energized) magnetized through the low voltage of the OTs.
The basket markings are a mystery to me and the only manufacturing marks on the cones is IREL? A search has yielded no information thus far.
Just wondering if anyone can identify these and offer any comments.
The design and finish are quite interesting and initial tests of these sans-enclosures seemed promising.
Thanks in advance!
Doesn't appear to be any rear-mounted motor structure so I'm guessing that the unusual flared rounded metal protrusions on the front and in the center of the cone are some form of motor.
They don't seem to exhibit any magnetic properties unconnected to the chassis so my guess is they become (energized) magnetized through the low voltage of the OTs.
The basket markings are a mystery to me and the only manufacturing marks on the cones is IREL? A search has yielded no information thus far.
Just wondering if anyone can identify these and offer any comments.
The design and finish are quite interesting and initial tests of these sans-enclosures seemed promising.
Thanks in advance!
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How so? Rear profile of your example clearly indicates a magnet/motor structure, albeit, not a substantial one, and no front-mounted metal protrusion of any kind (I know they aren't phase plugs on mine)
Seen many of your examples but they aren't remotely similar to the drivers I have. (Are they perhaps, manufactured by the same "IREL" outfit?)
For some reason I am prohibited from posting pics larger than 175 (or so) kb so perhaps the images of my mystery drivers were too small for you to discern the details I was referring to.
Thank-you nonetheless Wavebourn. I appreciate any possible avenues of exploration.
Seen many of your examples but they aren't remotely similar to the drivers I have. (Are they perhaps, manufactured by the same "IREL" outfit?)
For some reason I am prohibited from posting pics larger than 175 (or so) kb so perhaps the images of my mystery drivers were too small for you to discern the details I was referring to.
Thank-you nonetheless Wavebourn. I appreciate any possible avenues of exploration.
I have run across a few IREL, i'd have to dig out an archive to confirm or not, but IIRC they are Italian.
Your picture is kind of small, but they are not unique in having a front mounted motor with an alnico slug. I have had both Dual & Pillips drivers with the same.
Anitoly, lovely surround on those, a precursor to the Fostex UDR.
dave
dave
Your picture is kind of small, but they are not unique in having a front mounted motor with an alnico slug. I have had both Dual & Pillips drivers with the same.
Anitoly, lovely surround on those, a precursor to the Fostex UDR.
dave
dave
Yes, for some reason I can only post pics of 175kb or smaller. Perhaps because I am a recent DIY Audio member.
Thanks Planet 10. Any idea of the design rationale of a front-mounted motor? Space constraints weren't an issue in the console these were pulled from. What were your impressions of the Philips and Dual examples of such a design?
Thanks Planet 10. Any idea of the design rationale of a front-mounted motor? Space constraints weren't an issue in the console these were pulled from. What were your impressions of the Philips and Dual examples of such a design?
With 175 kb/image you could easily be posting 1000 pixel across images. I do note that your tiny thumbnails are hitting 45 kb... they should be 3-6kb given their size.
One way of getting such an anomalas size is to save a picture in photoshop as a jpg, This can balloon a tiny file like yours by embedding all sorts of metadata. If you are using PhotoShop, use "Save for Web"
dave
Your speakers look like have the same type of front mounted motors.
They were called 3GD-38E. I still remember juicy sound of that speakers. I believe it is possible to restore production of this speakers.
I don't see a front-mounted motor on your example though, which is why I am confused by it.
That is not it. The liit is actually 195kb, which is more than large enuff for posting on the forum. Your pictures, when resized & saved correctly should be on the order of 45-100kB
Your pictures are large (in kB) because of how you are saving them
For example the attached image is 49k,
dave
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Belay that... looks like i've had a set of those thru here.
dave
Here is an extract of my eBay blurb:
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Interesting Dave. Italian made speakers in a German console stereo? Seen more than a few vintage Farfisa branded enclosures with Philips driver complements, so I guess I shouldn't be too surprised.
I did a brief audition of my IRELs and they seem pretty sensitive....but more importantly seem to present an impedance load that my small EL84 and 6GW8 amps seem to love.
Think I'll experiment with these a bit. At worst they might make for a nice small set of office speakers in the right enclosure...just love the audacious design and the great finishing lengths this manufacturer went to...enameled baskets, embossed logo and head-scratching motor implementation. They're definitely conversation stimulators here as no one I've talked to has encountered anything like these.
Thanks again for everyone's help.
Wish Wavebourn would explain how his example is similar to mine. I don't see it, but am prepared to be re-edumacated.
I did a brief audition of my IRELs and they seem pretty sensitive....but more importantly seem to present an impedance load that my small EL84 and 6GW8 amps seem to love.
Think I'll experiment with these a bit. At worst they might make for a nice small set of office speakers in the right enclosure...just love the audacious design and the great finishing lengths this manufacturer went to...enameled baskets, embossed logo and head-scratching motor implementation. They're definitely conversation stimulators here as no one I've talked to has encountered anything like these.
Thanks again for everyone's help.
Wish Wavebourn would explain how his example is similar to mine. I don't see it, but am prepared to be re-edumacated.
I don't see it either, his has a dustcap where the voice coil and pole piece should sit. I'm glad he posted thou, worth it to see those surrounds..
Attached is a picture of some Philips & Duals with a similar motor topology.
dave
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First of all Dave...thks for moving my thread under the proper heading. And for all the additional pics and info. Seen most of these puppies before which was why the IREL's were so intriguing. There's no magnetism to these at all except when hooked up to live OTs which would seem to make them some sort of field-coil variation, would it not?
Given your vast driver/enclosure experience with testing, tinkering and design what were your impressions of the IRELS? I'm pre-supposing that the fact they went on to e-prey was a reflection of their sonic limitations?
It seems that the front mounted motors were and are currently employed for car audio as well as other space saving applications but an e-mail I received from a fellow in Europe claims IREL also made much large circular drivers with the same motor design and that, in fact, the magnets are energized by the output current of the amplifiers.
Given your vast driver/enclosure experience with testing, tinkering and design what were your impressions of the IRELS? I'm pre-supposing that the fact they went on to e-prey was a reflection of their sonic limitations?
It seems that the front mounted motors were and are currently employed for car audio as well as other space saving applications but an e-mail I received from a fellow in Europe claims IREL also made much large circular drivers with the same motor design and that, in fact, the magnets are energized by the output current of the amplifiers.
Much more likely that the magnet/motor design was just naturally sheilded.
I thot they were OK. They went up on eBay because at the time that was how i scraped by. I went thru literally thousands of old drivers. I am now at the point were i'm giving most of the remainders away (at least hundreds & hundreds)
dave
Yes, that's probably the freq. range on these as well. Thks for your observations picowall....Leo
Yes, that makes sense.
And sorry Dave, wasn't trying to imply you did anything wrong by putting them up for auction. Just don't like what it's become, which is why diyaudio is generally such a refreshing refuge. Your glowing reputation speaks for itself. Like you much of my enjoyment comes from learning something new, experimenting and sharing surplus or "won't ever get to items" with other enthusiasts. No offense intended.
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