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Bohlender Graebener RD50 Planar Transducer

Bohlender Graebener RD50 Planar Transducer

Brand:| Model: RD50
Specifications: • Power Handling: 70 watts RMS/270 watts max • Nominal Impedance: 4 ohms • Re: 4.0 ohms • Frequency range: 150-18,500 Hz • SPL: 88 dB 1W/1m • Net weight: 25.2 lbs. • Dimensions: 51-1/2" L x 4-11/16" W x 1-1/2" D.
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Product Details

Bohlender Graebener RD50 Planar Transducer

The RD series of loudspeaker drivers offer the systems designer the advantages of a thin-film, line-source transducer with very high performance potential for fixed installation sound reproduction. Unlike most exotic driver types, the RD Series models feature unmatched bandwidth, power handling and ruggedness, as well as the ease of an almost entirely resistive load to the amplifier. All models in the RD Series feature linear, push-pull Ceramic 8 motors linearly driving a polyester diaphragm whose moving mass is actually less than the air load. The bandwidth of the RD Series drivers is extraordinarily large, and is usable from as low as 150Hz to beyond audibility. Program power handling of the RD50 driver is 135 watts. The diaphragm is protected within a chassis made of three layers of heavy gauge, self-reinforced steel.

Specifications: • Power handling: 70 watts RMS/270 watts max • Nominal impedance: 4 ohms • Re: 4.0 ohms • Frequency range: 150-18,500 Hz • SPL: 88 dB 1W/1m • Net weight: 25.2 lbs. • Dimensions: 51-1/2" L x 4-11/16" W x 1-1/2" D.

Bohlender Graebener RD Series Planar Transducers cannot be shipped or sold to customers that live outside of the United States. There is no warranty extended to customers outside of the United States that purchase any of the Bohlender Graebener RD Series (including the RD75, RD50, and RD40) Planar Transducers from Parts Express.

Product Specifications
  • Tweeter TypePlanar
  • Impedance4 ohms
  • Power Handling (RMS)70 Watts
Bohlender Graebener RD50 Planar Transducer
  • BrandBohlender Graebener
  • ModelRD50
  • Part Number264-702
  • UPC844632052989
  • Product CategoryPlanar / Ribbon Transducers
  • Unit of MeasureEA
  • Product Rating
    (1 Reviews)
  • Weight27 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

Similar Products

View similar products to the Bohlender Graebener RD50 Planar Transducer
in the Planar / Ribbon Transducers product category.


Bohlender Graebener RD50 Planar Transducer
Bohlender Graebener RD50 Planar Transducer is rated 5.0 out of 5 by 1.
Rated 5 out of 5 by from Extremely rapidRD 50 BG is one of my favorite project!Theses planar are very fast to respond!It gives a extraordinary stereo image with a depth that surprise me each time!One hic, there's a sweet spot!;(But, its among my favorite driver!
Date published: 2011-10-29
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Product Q&A

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If your question requires design or troubleshooting information,
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Bohlender Graebener RD50 Planar Transducer

Would it be possible to get more mechanical details, especially with regards to baffle cutout? Looking online at some of the projects using the RD50, most people are only cutting an opening for the ribbon element leaving the ends covered.

Asked by: JamesB
This is the preferred method of mounting the RD series drivers. Contact me via email for dimensional drawings (including baffle opening dims) of the RD series drivers.
Answered by: OldSpkrNut
Date published: 2014-12-29

The overview has the frequency range up to 18500hz but the product details say the speaker is usable to beyond audible range. Does this speaker ideally need to be paired with a tweeter or is the response flat all the way up to the top of the audible range

Asked by: djdaveastro09
Whether this requires a tweeter or not is entirely up to the end user. 18,500 Hz is beyond most peoples audible range so a tweeter used above this frequency would likely be moot.
Answered by: MattP
Date published: 2014-08-13

What do they mean by Program power handling of the RD50 driver is 135 watts. How does this differ from RMS/70 watt ?

Asked by: Wildchild
Companies will rate their drivers differently. In this case, RMS is derived by using a single sine wave at a given frequency, which is harder on a driver than program material, IE: music. This is why program ratings are higher than RMS power because program material is generally a lighter thermal load on a driver.
Answered by: MattP
Date published: 2014-05-19

I want a center channel speaker with the RD 50 . I have 2 -55" tall Line arrays that set on each side of my 60" plasma TV Seeing how the Planars have a vertical dispersion, will this work without waves crashing into the l-arrays ?

Asked by: Wildchild
waves are going to crash regardless of orientation,placement or radiating characteristics,you cant stop that but you can change the net acoustical output(room response)by changes in proximity to room boundaries.
Answered by: unk2
Date published: 2014-05-21

Can you give an example recommended enclosure?

What would a good closed enclosure look like? Can I incorporate a woofer in the same enclosure? Would a trapezoid shape with a woofer at the base be a workable design?
Asked by: mcmillinamps
These drivers are closed back which means the enclosure will not affect the sound. These can share a chamber with a woofer.
Answered by: MattP
Date published: 2012-12-12

What woofers would be a good choice to pair with these?

I like the idea of these. I am currently building a line array and since these have a wide freq response I was thinking of doing a Martin Logan Electrostatic-esque type build with these. 8" or 10" in a 1cft box and then these above them. I don't listen at very loud volumes, I just don't want the sub to do all the low end work. I'd want some low-mid punch. If Bohlender Graebener made woofers I'd get a pair of those but since they don't, who would compliment these guys for some low punch around 90-300hz?Thanks in advance!
Asked by: Nonsuchpro
We have many options that will work well in this passband. The Dayton Reference series mid-basses would work well and are our best sellers.
Answered by: MattP
Date published: 2013-12-21
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