Hello, I have found someone with some original "NOS", Bohlender Graebener RG-75's OR RD-75's OR 1.9's. does anyone know the differences in these models? I am wondering which is better for a home line source. And overall what the difference were. I was reading recently about a fellow whom built a line source back when the RG-75 was first manufactured. He raved about it. But I am taking that with a grain of salt. I do know I would like to try it but I do not know much about them. Other than 6'-3" tall and can be run from 150Hz - 40KHz. At least that's what I have read. I cannot find too much on-line about them. I'm wondering if this is a deal or a bust. ANY help/info would be highly appreciated.
I am currently working on developing a line source speaker using the B&G Neo 3, Neo8 and Neo10 so I have a little experience with them but the RG-75 sound like the "pinnacle", of what B&G's, R&D came up with and actually manufactured. Even though only for a limited time.
I am currently working on developing a line source speaker using the B&G Neo 3, Neo8 and Neo10 so I have a little experience with them but the RG-75 sound like the "pinnacle", of what B&G's, R&D came up with and actually manufactured. Even though only for a limited time.
And if they are not a "bust", which would be best for my application? Or am I better off with the separate drivers?
most use them full range
a "highly modified" RD75 was used by Wisdom Audio, a later model used 50" BG line sources
some seem to think they are great mids but XO above 5 KHz
a "highly modified" RD75 was used by Wisdom Audio, a later model used 50" BG line sources
some seem to think they are great mids but XO above 5 KHz
Do you know if they were used all the way down to 150Hz? I also have a chance to buy his stock out at a discount "10%". So if anyone is interested.......Contact me. There is a very limited supply and I am not looking to make a profit if someone did go in with me.
But time is of the essence here.
Would you by any chance kow what "Wisdom Audio" would call highly modified? Or what was different?
My goal is to actually manufacture something similar for home audio right now.
"I am getting quotes for my first CNC mill machine for the current shop."
Up to now I've only, "flipped equipment", to finance my horribly cash debilitating, "Audiophilia", disease.
But time is of the essence here.
Would you by any chance kow what "Wisdom Audio" would call highly modified? Or what was different?
My goal is to actually manufacture something similar for home audio right now.
"I am getting quotes for my first CNC mill machine for the current shop."
Up to now I've only, "flipped equipment", to finance my horribly cash debilitating, "Audiophilia", disease.
http://www2.standardaudio.se/pdf/DATABLAD/RADIA/White_Paper_Pro-Line.pdf seems to indicate "1.9" is the "Pro-line" version with the PEN film
and
The 1.9 Pro-lines may be a deal but > the former Parts Express singles price for the RD75 isn't my idea of a bargain
maybe for someone desperate to repair a system, but not for a one-off build that can never be replicated do to the driver obsolescence
and
The 1.9 Pro-lines may be a deal but > the former Parts Express singles price for the RD75 isn't my idea of a bargain
maybe for someone desperate to repair a system, but not for a one-off build that can never be replicated do to the driver obsolescence
I agree it isn't exactly a bargain, but do you know of a similar transducer? Other than the Neo10 from parts express, "The absolute cheapest I can find them " is $200 plus shipping.
I am using the Neo8 which has a vertical output of less than 6" with a <2 inch gap in dispersion vertically between transducers and the Neo10 which has 8" vertical dispersion again with the <2" gap. The reason I want to try these so bad is because the continuous 71.2", "Subtracting the 1.8 inches", for vertical radiation that will allow a true cylindrical wave formation.
I currently need nine Neo8's or seven x Neo10's to accomplish what the RD-75 or 1.9 can create. BUT, at a cost of $900 or $1,400. With the Neo8, a crossover frequency well inside the human vocal range AND only a radiation of 54 out of the 72" vertical distance I do not like the actual vertical performance. The Neo10 can give 80% coverage "Acceptable", vertically with the same crossover point as the 1.9 or RD-75 but at a cost of $1,400.
So, In a way, for my current application it is "I believe" a deal.
Is there something else I could use with decent speed and similar sound characteristics available? I am kind of hooked on the "Mag Planar" specs and sound.
I am using the Neo8 which has a vertical output of less than 6" with a <2 inch gap in dispersion vertically between transducers and the Neo10 which has 8" vertical dispersion again with the <2" gap. The reason I want to try these so bad is because the continuous 71.2", "Subtracting the 1.8 inches", for vertical radiation that will allow a true cylindrical wave formation.
I currently need nine Neo8's or seven x Neo10's to accomplish what the RD-75 or 1.9 can create. BUT, at a cost of $900 or $1,400. With the Neo8, a crossover frequency well inside the human vocal range AND only a radiation of 54 out of the 72" vertical distance I do not like the actual vertical performance. The Neo10 can give 80% coverage "Acceptable", vertically with the same crossover point as the 1.9 or RD-75 but at a cost of $1,400.
So, In a way, for my current application it is "I believe" a deal.
Is there something else I could use with decent speed and similar sound characteristics available? I am kind of hooked on the "Mag Planar" specs and sound.
if youv'e got the scratch
Alcons RBN-Series - ultimate sounded high frequency Loudspeakers; where to buy collects some info
I'm curious about how bad the Danley Paraline would be with custom designed phase plug and wave guide instead of just accepting stacked flat sheet w/cutout geometry
perhaps 4-8x small CD and Unit/Synergy style summed mids
Alcons RBN-Series - ultimate sounded high frequency Loudspeakers; where to buy collects some info
I'm curious about how bad the Danley Paraline would be with custom designed phase plug and wave guide instead of just accepting stacked flat sheet w/cutout geometry
perhaps 4-8x small CD and Unit/Synergy style summed mids
Yah, That is part of my next project. Miniscule compared to my current work.
Hee hee, I started ordering material for it last week.
But instead of 3D printing, I'll be using "Corian" because it seems I have a free, unlimited supply, A steam oven to bring it to a malleable state and "adjustable", forming molds. That project is focused currently on the Neo10 as a transducer. Which is why part of my time now is spent designing my own type of Mag Planar.
The Paraline seem to work very nicely in theory. It's just that in practical application there seem to be allot of diffraction issues and other, "Unknowns".
Hee hee, I started ordering material for it last week.
But instead of 3D printing, I'll be using "Corian" because it seems I have a free, unlimited supply, A steam oven to bring it to a malleable state and "adjustable", forming molds. That project is focused currently on the Neo10 as a transducer. Which is why part of my time now is spent designing my own type of Mag Planar.
The Paraline seem to work very nicely in theory. It's just that in practical application there seem to be allot of diffraction issues and other, "Unknowns".
Have you checked what Wisdom Audio wants for their's? I'd say if you can get your hands on a pair or more grab them while you can!
They just emailed me and said that they just talked to "Igor Levitski" one of the original designers of the transducer. Apparently he said that the SC-75 is exactly like the RD-75 which was the OEM. Just of newer manufacture. And also out of production. I think the 1.9 model is the "pro series" model. I'll try calling Wisdom Monday.
You mean the transducers themselves? Octavia??
How many should I purchase? Anyone interested in buying a set already made with the SC75? Made with NOS transducers?
You mean the transducers themselves? Octavia??
How many should I purchase? Anyone interested in buying a set already made with the SC75? Made with NOS transducers?
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Well,
Well, about 60 of those, "in the three different models" which are about the same thing", 42 of the sc and rd 75's is my understanding.
Well, about 60 of those, "in the three different models" which are about the same thing", 42 of the sc and rd 75's is my understanding.
There are so many links about diy projects using this driver. Nearly all of them are highly complementary of the driver as long as you do a notch filter around 5K hz and pass off the lows below 250 Hz or so. Maybe it's just me but the price per each I'm not clear on but in all their variations they seem a great driver. I've been hauling my ancient Quad electrostats around for so many years that buying into a project with an obsolete driver wouldn't be a concern and I suspect the 1.9 model is so robust that it would never be a worry (ok maybe once you pass them on to the grandkids). One "upgrade" or mod or whatever you want to call it that got good press was to put a half roll around the edge to make sort of a horn aperture loading. As I recall either B&G or Wisdom did some in wall installations that ran somewhere around $100,000. One final comment, I know of one concert pianist who is as much an audiophile as anyone you will ever meet, and he swears by them. No driver, speaker, is perfect, but I'm quite sure with the proper care and feeding these could get you into the 1% category.
PS: I have no idea of your budget, but, a set of them in a dedicated room could be the heart of one hell of a home theater.
A project that uses the RD75 in a near full range application is this one:
Bohlender-Graebener RD75 - The Ultimate 2-Way System | Perry Marshall
Bohlender-Graebener RD75 - The Ultimate 2-Way System | Perry Marshall
For years I have lusted for these drivers and then they went out of business. I would be very interested in purchasing a pair.
I think he has been trying to call me but that landline was cut underground.... So i am still waiting to hear how many are left. Just the shipping is $200 per piece because of the size and the fact that it has to be shipped as "freight".