What matters is does the change result in an overall improvement? This would be a subjective judgement so the only way to know if I like it is to perform the "upgrade". If I don't prefer it, I can change it back. I'm curious how the change effects the sound before I do it. Fried must have published some background to why they made the change. Interesting they went back to the earlier configuration with the C6L. Were the C progressions just driver changes or did the cabinet change?
Decreasing the cap value of the Zobel on the C3L would flatten the woofer impedance higher in it's response.
I think Fried was trying to extend it's response a little.
The Zobel on the C6L uses 2 mfd and 10 ohm Re.
The crossover schematic is on post #28.
Fried changed crossover values claiming it upgraded the performance of the speaker.
The C3L enclosure is exactly the same with the C5L and C6L models.
Also the same is true with the enclosure of the O4-O6 models.
The C1-C3 use the aperiodic truncated pyramid until the transmission line C3L design was implemented.
The C1 used the Dalesford 6.5" bextrene cones with the Dynaudio D-28H tweeter.
There were two different Dalesford woofers used in the C1 model.
The D153/50 were in the early models.
I was able to purchase a pair of the D153/80 which were used in the C models sold for
professional monitoring applications.
These have a much larger motor structure to increase their power handling.
Dalesford went out of business so Fried had to change his source of drivers.
The C2 used the former Transparent Sound poly cones with foam surrounds with the Scan Speak 2008 tweeter.
The C3 used the Carboneau poly cones with the Scan Speak 2008 tweeter.
The first Carboneau drivers used the foam surrounds.
Later models have a butyl rubber surround.
The C3 came with the option of using the upgraded transmission line enclosure and was named the C3L.
There was never a C4L model even though the C3L was the fourth generation of the C models.
I remember the first C3L I listened to used the Scan Speak 2010 tweeter which was later changed to the Hiquphon OW2-92FS.
The short lived C5L model used the Focal 6K412L kevlar sandwich cone with the Hiquphons.
Fried included in one of his papers how Focal was not truthful with the response curves of their drivers.
Every Kevlar sandwich cone has a breakup above the rolloff which can't be attenuated with a low order crossover.
Others have discussed it on other forums.
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I know that Fried was trying to get Scan Speak to make a 6.5" carbon fiber driver to replace the Focal drivers.
Since Scan Speak's tool and dies were set up for 7" and not 6.5" is probably why it never happened.
This is one of the reasons why he had Gefco source the drivers for his last generation of speakers.