Drop off in treble - Audax HD3P

[Tony Moore]

Hi All,

I have been using my IPL S5TL Gold speakers now for around 5 years and I have always been very happy with them. Recently though I've been thinking that the treble is reduced on what I remember. This week I was running in my Kel84 with Jensens refitted to sell it using my Ruark Tallisman speakers and realised just how much more HF there should be! I've tried the Kel84 on my S5TLs and sure enough it's not the amp. I know it's all about what you get used to but I can't help think that perhaps the treble from the HD3P has reduced over time.

Does anyone know if this is possible? Has anyone experienced anything similar? Or course it may just be my ears!

Cheers,
Tony

[acorn]

Hi Tony

Apparently some of the HD3P suffered from gas leaks, this gas keeps the diaphragm tight so any loss in gas perssure would result in the condition you described.

Regards Acorn

[Yellow]

Tony,

Is everything OK with the crossover? It looks a little different to a standard x/o with what looks like some sort of Tx coupling.....is that right? I have absolutely no experience with these units whatsoever though. You haven't go t a "high-resistance" joint somewhere (dry-joint) that is causing a problem?
Chances are though, it's the driver.

Hope you find the problem!!

Neil.

[Tony Moore]

Hi Neil, Acorn,

Yes it uses an impedance matching tx Neil. Both speakers are the same level in HF though so I'm thinking that if this _IS_ a problem then it could be related to the gas leak issue and even then both drivers would have to have depressurised by roughly the same degree. And would I not see something wrong with them?

I will go in to the crossovers and check out joints and look for anything wrong.

Thanks for your help.

Cheers,
Tony

[Little Mick]

Hi Tony

I have had a couple of pairs of those and they are not the brightest in the world which I quite liked at the time, when going into the xovers don’t forget the input pad on the HD3P board.

[MarkL]

Hi Tony - I had this problem - one way you can tell it is the tweeters is when we (finally) get some high pressure weather - the high fequencies soften further. You may even notice some wrinckling in the metal foil if they've lost a lot of gas. If you can get a replacement, the later ones are gas-tight.

Mark

[Triode1]

I think I have this too - I've not used them as much recently and they wrinkled during the cold weather this winter. They look right now, but sounds slightly soft.

Has anyone investigated whether it is possible to re-gas them. If I am right, there are two membrains close together [must be some gas between them], then some gas behind them to form the slight domed shape.

Failing that - have any KLS3 II owners replaced the tweeters with something else?

[rong spellin]

Originally Posted by MarkL

If you can get a replacement, the later ones are gas-tight.

Here's some relatively cheap HD3P's in the US,of course they are impossible to find.
http://www.meadowlarkaudio.com/pow/liquidationList.htm

[Brian]

Originally Posted by rong spellin

Here's some relatively cheap HD3P's in the US,of course they are impossible to find.
http://www.meadowlarkaudio.com/pow/liquidationList.htm

$1600!!!

They're really good, but I'd sell mine for that, like. Possibly.