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Concertos...worth fixing and replace tweeter?

 
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mikeytheo
Intermediate Contributor 25+


Joined: 16 Apr 2007
Posts: 33
Location: Sydney Australia

PostPosted: Wed Apr 18, 2007 11:33 am    Post subject: Concertos...worth fixing and replace tweeter? Reply with quote

Many thanks on the Celestion feedback. I think I'll stick to the T27s.
However, have just collected the speakers and they are in pretty average condition. Original cloth with surround crumbling from what looks like water damage. Many scratches on the cabinets. Speaker connects missing on one and the one tweeter out (haven't wired them up so hope this is all!)

Apart from cosmetics which do not overly concern me, I have found that the tweeters are the 6535s. I think these are one of the earliest Concertos. I have found a set of 6340s on ebay. I assume that these are earlier (this site mentions usage in the first LS3/5), but they are advertised to have come out of Concertos. The ebay set of 6340s have only one working - that would leave me with one 6535 and one 6340. Could this work ok - or am I better off just sourcing a set of 6535s to keep original - or upgrade to a pair of 1032s ? (is this indeed an upgrade?).

Also, binding posts - is this a common upgrade as the surviving pair look very unsubstantial.

One final question for now - the rear of the cabinets are flaking - would a cover of varnish be an ok solution - or is that sacrilege?

A lot of questions I know, but I am new to all this and would like to get it right. Being in Australia means pricing can be a bitch with exchange rates, so am looking at all options. Thanks again , M
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ColinR
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Joined: 31 Jul 2004
Posts: 1175
Location: Staffordshire

PostPosted: Wed Apr 18, 2007 7:21 pm    Post subject: Reply with quote

As the earliest Concertos used a SP1002 with 6uF and 7uF T-sction for the A6340 tweeter, a slight tweak of the twin 5uFs of the SP1004 of the A6535 may be required. Let your ears decide.

You've got the earliest plastic screw terminals I presume, use some small bolts and automotive ring connectors as speaker cable terminations.

That white fleck finish is horrible, wire-wool all the loose stuff off and repaint.
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Last edited by ColinR on Thu Apr 19, 2007 11:36 am; edited 1 time in total
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mikeytheo
Intermediate Contributor 25+


Joined: 16 Apr 2007
Posts: 33
Location: Sydney Australia

PostPosted: Wed Apr 18, 2007 11:28 pm    Post subject: Reply with quote

Thanks for the quick reply. To be honest, I have zero experience in any technical matters to do with audio, so I cant really see myself tweaking the 6uF and 7uF T-section, as at this point I am proud to have located the wiring! Will go for the 6340 and as you say, let my ears (which are not golden) decide. I did have a thought though - is it possible that the tweeter is actually ok and the crossover is at fault? Assume a swap of the tweeters will immediately provide the answer.

The speaker connections are tiny little metal screws (approx 1mm thread) with pink washer. Can't really see them holding thick gauge speaker wire comfortably. Was considering just buying new terminal posts and fitting.

As an aside, how can I best date these speakers? The badges (yes, still there!) are tiny little KEF in the ellipse, unlike others I have seen with the stylised K. The cabinets are a muddy brown colour, not woodgrain, so they are not as attractive as the later versions.

Just for interest on what Concertos are going for in Australia, a mint pair went for $420 recently (ebay - too far away to pick up for me). My pair which I would say are in reasonable to poor condition I picked up for $260 (ebay - but the description was not as revealing as it could have been).
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ColinR
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Joined: 31 Jul 2004
Posts: 1175
Location: Staffordshire

PostPosted: Thu Apr 19, 2007 11:36 am    Post subject: Reply with quote

Remove a bass unit, there'll either be a date sticker on the back of it or it will be stitting in the cavity.

The date will be of the form week xx, year yy.

Week one for older speakers I suspect was in July.

Soldering a 1uF and 2uF capacitors in parallel with the the existing 5uF components on the rear of the pcb will be no more difficult than fitting and soldering leads onto binding posts btw.
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IsakAlexander
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Joined: 05 Jan 2007
Posts: 18
Location: Norway

PostPosted: Wed Jun 27, 2007 6:43 am    Post subject: Reply with quote

Were thinking of putting new veneer on my cabinets, haven`t decided on wood. One I like is mahogany, the original teak doesn`t blend in with the rest of the livingroom. Also the cabinets have got some waterdamage in the corners. Any suggestions in types of wood?

Last edited by IsakAlexander on Fri Jun 29, 2007 1:02 pm; edited 1 time in total
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ColinR
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Joined: 31 Jul 2004
Posts: 1175
Location: Staffordshire

PostPosted: Wed Jun 27, 2007 11:11 am    Post subject: Reply with quote

Visit your "local" yacht chandlers or boatyard and get the necessary product to remove water stains from dingys / keelboats constructed from teak, mahogany, etc., marine ply.

For industrial chemists acquire some oxalic acid.

For non-chemists and cooks, boil up some Rhubarb leaves in a steel pan (oxalic acid dssolves Aluminium) reduce and apply with fine wire wool to lift the grain.


Test all products first where it cannot be seen.

Keep all the above from pets and children you like, for injestion can prove fatal.
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IsakAlexander
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Joined: 05 Jan 2007
Posts: 18
Location: Norway

PostPosted: Fri Jun 29, 2007 1:00 pm    Post subject: Reply with quote

It`s not stains, the veneer have come off in the corners. Crying or Very sad Anyhow, I will put on mahogany veneer instead. Darker wood will blend better with the other furniture.
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