Repairing ribbon drivers and TCO

[tiroth]

I've been looking seriously at a ribbon in the ~5" range for my next project. It seems that the most obvious candidates are Raven R2, Aurum Cantus G2, Fountek JP2. Are there differences in how repairable these speakers are?

I know Peter Daniel has said that the R2's are easily repaired and replacement elements are ~$5. I've also read some posts on Madisound that imply that the Fountek ribbons need to be professionally replaced and tensioned ($100 yuck!). I've heard nothing about the AC.

Anyone have info on replacing the ribbons in the cheaper Aurum Cantus and Founteks? Something tells me the total cost of ownership may well be higher if repair costs are very high...these ribbons do seem to eventually die, especially if they are being used in an unproven design.

[tiroth]

Talked to Madisound, they are currently charging $19 per tweeter for repairs. They said that the elements are not field replaceable due to the need for "special tools".

They seemed a little annoyed when I inquired about buying the elements directly but did say they would sell them for the same $19 each. Madisound stocks the elements but doesn't have a huge supply; in the event that Fountek goes out of business, no more repairs available. That is my main fear and what is behind the desire to have replacements on-hand.

So it looks like repair cost of Founteks is about 4x that of Ravens. I'm still hoping someone will post info about Aurum Cantus.

[tiroth]

Via googling I've discovered a second pricing page on the e-speakers.com site that lists the following prices for replacement Aurum Cantus elements:

G1 $15 each
G2 $10 pair
G3 $15 pair

Not bad.

[tiroth]

I've now received instructions on repairing the AC from Andre at www.e-speakers.com. (thanks!) The process sounds very easy...evidently there are a set number of corrugations which makes tensioning a no-brainer.

[RussianBlue]

tiroth,
how are the G2s in terms of dynamics in comparison to a good softdome (ie. Morel MDT 33, Seas Millennia etc)? Has anyone heard them side by side with the Fountek Ribbons?
Thanks for your help.

Cheers

[tiroth]

I would love to know the answer myself. I don't yet have any of these tweeters. I am trying to determine if there is a difference in quality between G2 and G2si that is worth the cost.

I have read a lot of comments about ribbons in general, the the consensus seems to be that they are second to none in terms of dynamics. Yet, some people do not like the "sound" of ribbons, so they are not for everyone.

Personally, I am steering clear of the Fountek. They are much more expensive to repair, and I have yet to see even one person say they sound good versus the alternatives. I haven't heard any negative comments either, to be fair.

[JohnL]

I have been working with a JP2 in a center channel and I have a pair of JP3s sitting here waiting for boxes. I have some other ribbons around here and would say they compare very favorably to anything else I've tried (AMT, Apogee ribbons, Focal metal domes, vifa soft domes). I haven't heard the AC or the Raven, but for the price difference it might pay to go with fountek and keep a spare driver around JIC.

John

[rah]

Hi all,

I wanted to use the Fountek JP2 myself, so I had a chat to
Troels Gravesen (fellow DIYer who has used the Fountek), this
is what he told me, hope it helps.

From Troels Gravesen:

> Here's the procedure as described by the Fountek company. I haven't
> come around to make a photo session of how to make your own
> ribbons. But I will some day. If you have to replace a ribbon,
> practise on a home-made ribbon made from 11 micrometer household alu
> foil. Corrugate it and try mounting it between the magnets. You may
> need a pair of wooded pliers to handle the ribbon. First time it's
> difficult, next time is a piece of cake.
>

How do you tension the ribbon in side the tweeter? Is there some
gauge or tool required for this? or is it simply by trial and error?

> Yes, this is really just trial and error. When the ribbon is
> corrugated you can very gently try stretching it without flattening it
> again and it just needs some minor elasticity in the magnet
> gap. Aluminium really has very low elasticity - it a very dead
> material and doesn't regain it's shape after deformation.But the
> tension does not appear to be very critical in gaining proper response
> from the driver. A little but strange, but so it seems.

You can read more on Troels site:
http://home1.stofanet.dk/troels.gravesen/

So, as far as I can see, I don't see a huge problem with using the
Founteks. Once you sort out the design (..and if it's a good design)
you won't blow the ribbon in every day usage.

As for sound quality, I've only heard positive things about it.
Someone compared the JP2 with an AC G2 (which is smaller), and
likeed the JP2 better, they said the sound had more body (probably
because of it's size). The JP2 is closer to the G3, only being
fractionally smaller.

Rahul.