Fried Transmission Line Satellite and Subwoofer Design.

JimPA

Junior Member
Did Fried ever use the KEF B110 in a transmission line like the C3L? The H satellites are just sealed boxes with foam strategically placed.
No he didn't use the B110 in a transmission line. enclosure.
If one would build a scaled down version of the C3L I am sure they would work fine.
 

Salectric

Senior Member
Jim,

What type of wood did Fried recommend for the satellites?

Which 6.5" driver and which tweeter do you recommend of the units still available? Perhaps you will be coming to that when you get to the crossovers.
 

JimPA

Junior Member
Jim,

What type of wood did Fried recommend for the satellites?

Which 6.5" driver and which tweeter do you recommend of the units still available? Perhaps you will be coming to that when you get to the crossovers.
Back then he stated 3/4 flake board for the C3L and O4 enclosures.

I used 1" industrial grade for the subwoofers which is primarily used for countertops.
For constructing the transmission line of the O4 and C3L enclosures 3/4" for the interior pieces.

For the satellites 1" for the front baffle and back of the enclosure.
He stated to use 3/4" for the sides pieces for the C3L transmission line.
Making the enclosures wider would affect imaging.



I have always used the 3/4" particle board with the small flakes compared to the less expensive 3/4" with the larger flakes.
I found that cutting precise 7.5 degree angles is easier with the 3/4" particle board compared to using mdf.
The 1" industrial grade is listed as mdf in the the lumber yard catalog even though it isn't really mdf.

Both the C3L and O4 are so well braced with the interior pieces of the transmission line enclosure resonances
shouldn't be an issue.

I would use the Hiquphon tweeters.
scanspeak-classic-p17wj00-6.5-woofer or the
2-wool-cone
One of the previous owners of Fried Products was selling the Silver Flute 6.5" as replacement drivers for the C3L with a new series crossover design.

The Gefco drivers are not available anymore a photo of the 6.5" model below.
The Silver Flute have wool in their cones to dampen resonances like the Gefco models made for Fried.
DSC_0033.JPG
DSC_0122.JPG
 

JimPA

Junior Member
I was just browsing through the Madisound catalog and came across the ScanSpeak 15W/8530K-00 5.5" Revelator Woofer. That looks very promising. Have you ever tried one?

https://www.madisoundspeakerstore.com/approx-5-woofers/scanspeak-15w/8530k-00-5-revelator-woofer-low-qts/

That woofer is also used in an interesting finished design with the OW1 tweeter called the Carrera:

https://meniscusaudio.com/wp-content/uploads/2015/12/Carrera-Write-up.pdf
I have listened to the Totem Hawk that use the 15w Scan Speak woofer and preferred it's midrange over some of their other models.
specifications


Also the Scan Speak 7" would be a little to large in Sd. for the C3L enclosures.
It's disappointing that don't make a 6.5" version of their revelator line.
IMHO it's because they use the metric system.

Once I heard the Scan Speak carbon fiber 17w model in a pair of Merlin speakers with the Dynaudio Esotar tweeters and really liked their performance.
 

JimPA

Junior Member
These are some of the Fried crossover plans.
These are for the C2 satellite and either O2 or SM2 subwoofers.
The SM2 use a 12" subwoofer.
The first one use a parallel crossover design.
Fried parallel.jpg
The below schematic is a series crossover design.
This is when Fried finally switched to all series resonant crossover circuits.

You can see that the exact same crossover values are used but the layout was changed.
The subwoofer use a 12 mh 14 gauge air core inductor.
The mid bass driver us a .5 mh 18 gauge air core inductor.
Fried always choose 18 gauge for the mid bass driver.
No zobel is required for the subwoofer crossover in a series design.

DSC_0052.JPG

There were a few versions of the C3L crossover.
The original C3L crossover is a pdf file.
Also included is a new crossover for the C3L enclosure using the Hiquphon tweeters and Silver Flute 6.5" driver.DSC_0161.JPG
The below schematic has the C3L values crossed out and the C6 and O6 values hand.written.
I was told the values and had to right them down LOL.
DSC_0168.JPG

The schematic below has the C5 crossover that use the Hiquphon tweeters and Focal 6K412 driver.DSC_0161.JPG
 

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JimPA

Junior Member
Some might wonder what a series resonant circuit is.
A resonant circuit is a circuit where the inductive reactance of the coil is equal to the capacitive reactance of the capacitor.
You have a resonance point in the frequency response where both the inductor and cap cancel each other out.
This is determined by the values of L and C.
At this resonant impedance will be at it's lowest and current will be at it's highest.
On either side of this point voltage will be higher.
With a parallel resonant circuit all of these attributes are exactly opposite.
At resonance the only opposition to the current is the resistance of the inductor.
When you have a resonance in a series circuit you get a step up in voltage.
The opposite happens in parallel in that you get a step up in current.
For every halving of resistance in the circuit you get a doubling of current and voltage.
This is why it's important to use air core inductors instead of iron core in the Fried designs.
 
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Salectric

Senior Member
Jim,

So in terms of drivers that are currently available, you would recommend the ScanSpeak P17WJOO and the Hiquphon OW2-92FS? And perhaps the series crossover shown as “C-6” on your pdf file? I realize the attenuation network might need to be tweaked but it would appear this crossover should be ok otherwise. Do you agree?

I have an old Fried C brochure that makes a big deal about the rounded edges of the front baffle. Yet the later C models seem to have gone back to right-angle edges. Is that correct?
 

JimPA

Junior Member
Jim,

So in terms of drivers that are currently available, you would recommend the ScanSpeak P17WJOO and the Hiquphon OW2-92FS? And perhaps the series crossover shown as “C-6” on your pdf file? I realize the attenuation network might need to be tweaked but it would appear this crossover should be ok otherwise. Do you agree?

I have an old Fried C brochure that makes a big deal about the rounded edges of the front baffle. Yet the later C models seem to have gone back to right-angle edges. Is that correct?
The C models are all rounded.
I used a sander to round mine off a bit.
The first C3L crossover would be a better choice for the P17WJOO having a 2 ohm Re in series with Hiquphon tweeters with a 18 gauge .5mh air core inductor.
All that would be needed to change is the zobel and possibly the Re value in series with the tweeter if the 2 ohms wasn't flat.

Fried tried to eliminate any resistor in series with the Hiquphon tweeter.
The later crossover used a 30 ohm Re in parallel of the tweeter but he went back to the earlier design I was told.


You might recognize Trelja from Audiogon.
i have never met him but he thinks the Silver Flute driver might be better then the P17WJOO.
The Silver Flute is a paper wool composite cone.

The C6 and O6 Gefco composite cones have a very low voice coil inductance.
Fried used these with his MARS ambience recovery circuit.
Each speaker had the 6.5" and 10" drivers playing both channels.
One voice coil played the left channel and the other voice coil played the right channel in each speaker.
I am not sure why he abandoned the use of the MARS circuit.

i have enclosed the Studio V brochure,
These use the Gefco 6.5" and 8" drivers with the Hiquphon tweeters on a flat baffle.
72047
After Fried discontinued the Mars circuit each 6.5" and 10" driver had both 10 ohm voice coils wired in parallel.
This lowered the voice coil inductance in each driver.

Another thing Fried did he used the voice coil inductance of his 6.5" drivers as the inductor value in his series satellite crossovers.
The Gefco 6.5" have a voice coil inductance of .35mh when both voice coils are wired in parallel of each other.
 

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JimPA

Junior Member
This Scan Speak driver would work in the O4 enclosures.
The Vas is a little higher then my Dalesford and Gefco 10" drivers.
8565-00-10-woofer
Fried used highly compliant drivers in all of his transmission lines.
My Fried Dalesford 6.5" Vas are 35 liters the Gefco 6.5" Vas are 30 liters.

Look at the reviews of the Silver Flute 6.5"
2-wool-cone
Most drivers are not suited for a series crossover design.
One needs a driver with a smooth roll off when crossed over to the tweeter.
This is why Dr. Raines choose the Silver Flute when he owned Fried Products after Fried passed away.
post

Neither Joe Trelja or Dr. Raines have ever heard any of the old Dalesford that I have.
I haven't emailed Joe in a long time.
He does live in my county closer to Philly than me.
 

JimPA

Junior Member
Salectric I found another thread about some of the drivers that have been used in the Fried designs on Audiogon.
help-with-making-a-decision-fried-studio-v-mars
One thing about the P17WJOO driver is that it's a stock unit.
PSB used an oem model if this driver that have a longer xmax.
These were used in the 90's with a two way model.
I read a review of this model in the former Speaker Builder publication.

Fried claimed all of his oem 6.5" drivers were a duo cone design.
The dust cap shape help extend the response resulting in a low mh.
All of the 6.5" drivers Fried used had a 1" voice coil diameter.

Poly cones are going to have a different sound then a paper composite cone sound.
 

JimPA

Junior Member
Here are some videos of my speakers done with a cellphone.


My son took this video about 25 feet away from the speakers.
The highs and lows were diminished due to close miking.
 
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Salectric

Senior Member
Salectric I found another thread about some of the drivers that have been used in the Fried designs on Audiogon.
JimPA,

I just won an auction for a NOS pair of KEF B200 SP1022 woofers which, as you know, are the woofers used in the Fried H and M speakers. I am not totally sure what I will do with them just yet but this was too good a deal for me to pass up. The SP1022 has tight, detailed bass and it goes very deep in the H transmission line. The downside is its limited power handling.
 
I too, keep an extra pair of the SP1022's on hand; just in case I overdrive my model H.

I have only recently begun to follow this thread and I feel such a loss over what might have been, concerning the sharing of knowledge and talent had we met years ago, as I lived in Bucks County for several decades.
My father knew Bud during my college days but I never had the chance to meet him. My father and I designed and built many speakers over the years and I have continued on with that hobby.

Interesting thread.
 
New member here so hello to every one. Thanks go out to JimPA for all the design information posted for the Fried C3/L and is how I stumbled upon this forum.

Background:
Last year I purchased an original pair of the C3L speakers off Craigslist. They have the Carboneau 6.5" woofers and whatever tweeter they would have come with. One of the surrounds looks like a screw driver impaled it. I repaired it with silicone best I could. The cabinets maker did a good job of building them and I'd like to upgrade them with new woofers and matching crossover. JimPA's posting will allow me to confirm the cabinets were built per specifications. He mentioned various drivers that have been used as replacements for the Carboneau drivers.

Question:
What is the most suitable replacement driver that is currently available?

Aside: Back in the early '80s, I built from kit a pair of C1 speakers and purchased a model T sub-woofer from my dealer. Later I built a pair of model O subs. As you can imagine, these speakers left me many years ago. I didn't follow Fried products after that so I was out of touch with anything they developed later. I'd like to clone a Model T sub-woofer (I preferred it to the Os) at some point as I have a pair of large gauge coils in storage. A motor rewind shop made them for me in the mid '90s and are very heavy.
 

JimPA

Junior Member
New member here so hello to every one. Thanks go out to JimPA for all the design information posted for the Fried C3/L and is how I stumbled upon this forum.

Background:
Last year I purchased an original pair of the C3L speakers off Craigslist. They have the Carboneau 6.5" woofers and whatever tweeter they would have come with. One of the surrounds looks like a screw driver impaled it. I repaired it with silicone best I could. The cabinets maker did a good job of building them and I'd like to upgrade them with new woofers and matching crossover. JimPA's posting will allow me to confirm the cabinets were built per specifications. He mentioned various drivers that have been used as replacements for the Carboneau drivers.

Question:
What is the most suitable replacement driver that is currently available?

Aside: Back in the early '80s, I built from kit a pair of C1 speakers and purchased a model T sub-woofer from my dealer. Later I built a pair of model O subs. As you can imagine, these speakers left me many years ago. I didn't follow Fried products after that so I was out of touch with anything they developed later. I'd like to clone a Model T sub-woofer (I preferred it to the Os) at some point as I have a pair of large gauge coils in storage. A motor rewind shop made them for me in the mid '90s and are very heavy.
The C3L use the Hiquphon OW2-92-FS hiquphon.htm.
The only suitable drop in replacement woofer is the Vifa P17WJ00 scanspeak-classic-p17wj00-6.5-woofer for the existing crossover.
I have never tried this woofer but it's response curve is similar to the 6.5" drivers used by Fried.

One of the former owner's of Fried Products was selling the Silver Flute 2-wool-cone as a C3L upgrade.
This woofer has 6 holes and the baffle would have to be drilled to accommodate the driver.
The hole routing might have to be enlarged for it to fit.
I have never heard the Silver Flute driver but others that have used it like it's performance.
It would require a new crossover.
The last two pages of the document show the crossover for the Silver Flute driver.
I am glad this forum accommodates large files being uploaded to threads.

I would enjoy seeing some photos of the Fried drivers and enclosures you have.

The O4 enclosure IMHO is the best 10" transmission line enclosure designed by Fried.
Being deep it has less internal reflections compared to the O1 enclosure
It's .5 cubic feet larger than the O1 and T enclosures and is flat to 22-23hz.

I would get the butyl rubber surrounds replaced on the C3L drivers.
Fried did use foam rubber surrounds on the first C3L drivers then later switched to butyl rubber.

I know that the butyl rubber surrounds on my C6L Gefco drivers are thicker then most surround replacement kits.
One of Fried's former partners gave me a C6L driver that had a short in one voice coil so I dismantled the driver to see the voice coil.
This is when I noticed how thick the surround is.
 

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New Member too, I also want to thank JimPA and every one else who made this thread possible. I have a vintage pair of B2's from working at a HiFi store in the 70's and am now working on model C clones. Funny thing though I have realized through the years, it was not for the love of music that made these great speakers. It was finding music that brings out the passion of these speakers and the rest of the audio system. Got to honor those that designed and made such great audio equipment back in the day; like Bud Fried - Thanks
 
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