Rattle in LDR 5.2

[Tako]

Hello, I registered for the following:

Last week I purchased a set of 14 year old Piega LDR 5.2, they are in pristine condition, exept for one thing: On of the speakers "rattles" when playing low frequency's , even at low/moderate volume levels. It does not sound like a broken woofer, and appears to come from the lower bass-port. When I touch the speaker cloth (and only the cloth, without touching any wood or metal) covering the region of the lower bass port ,even lightly, the rattle stops.
My first thought was that maybe something hard had gotten caught in the fabric at one point, and the air flow from the port makes it rattle, but I can't find anything from the outside.

I have 2 questions:

1: Any idea what might cause the rattle, I'm inclined to think it can't be anything structural if even the lightest touch of just the cloth stops it.

2: How do I remove the speaker grille? I'd like to check the inside of the cloth for foreign objects, and maybe check/tighten the screws on the drivers, but I can't figure out how to get to them. At first I thought I'd be able to just slide out the grilles downwards, but apparently this is not possible because the upper bass ports' edge protrudes from the front panel about 0.5 cm, blocking the grille.

Sincerely,

[Tako]

An update: Some flash photographs allowed me to see through the grille cloth and pinpoint the problem: The edge of the upper bass reflex port has an anomaly (Rough plastic bit on the edge) which prevented the grille from sliding out. I was able to push it back through the cloth and remove the grille.

Without the grille, the rattle is gone, but the wood frame of the grille does not appear to cause the rattle, which seems to originate from the actual cloth itself. (pushing the wooden frame does not stop the rattle, lightly touching the cloth does...?)
I've checked the inside of the cloth for any foreign objects, but found none, the only thing I can think of , is that the sound is actually caused by the cloth, probably not as tightly stretched as it was 14 years ago, "slapping" against the wood frame around the bass ports because of the air-flow, which could probably be easily solved by applying some spray-on glue between the cloth and the wooden frame of the grille.

Although the main problem (removing the grilles) has been solved, any thoughts on preventing the rattle are still appreciated.

[Tako]

Also, feel free to answer in German, I can read it pretty good, but don't feel I master it enough to explain technical details.

[andy_]

Hi Tako

that will help...

but I think, you should wait, until Kurt (kds) has time to answer you...
that's because you own an "old" speaker...

have fun without the grille

Andy

[Tako]

Thanks Andy!

They are "quite enjoyable"

I just put the grilles away for now, as they look fine without them.
Since I've confirmed the rattle is just the grille, I'm not really worried about it anymore. I have a somewhat "weird" taste in music: Movie Soundtracks and Ambient music that often contains lower frequency information than other genres, which has caused some "grille rattling" on a few other speakers I've owned in the past.

The LDR 5.2 handle these (and other) frequency extremes VERY well, in fact, they are among the finest speakers I have heard, both sound quality and build quality wise. On top of that they are very user friendly: Easily driven by a modest amplifier, not too fussy about placement and with a great dispersion pattern (They could almost be used as near field monitors: there's almost no change in sound wheter you are 75cm away from them or 4m).

They have also apparently solved a problem I've been having for a long time: With most speakers I've owned it has been impossible to get a solid mid-bass on my listening position, standing waves seem to cancel out a lot of low frequency energy, often bass would be strong when standing up, and completely disappear as soon as I sat down. The LDR 5.2 somehow doesn't suffer from this, bass stays surprisingly even throughout the entire room, only picking up in strength against the back wall. I wonder if this is because of the twin bass ports placed over a meter apart?

Finally they are a real bargain on the second hand market, I payed 500€ for them, in mint condition. A pair of B&W 802s3 or Thiel CS3.6 of similar age and list-price usually costs about 3 times that much on the Dutch second hand market!

To say I'm happy with them would be the understatement of the year

[kds]

Hi Tako

It is quite possible that the tissue has lengthened over time.

If you have technical skills, I would recommend to you to expand the hole around the BR pipe in the front grille. You should strung the frame with new tissue with well tension.

Best regards
Kurt

[Tako]

Thanks Kurt, hadn't thought of expanding the holes in the grilles

I'm going to try both your tips as soon as I feel like putting the grilles back on. (I'm too busy just enjoying my loudspeakers at this point) I might even put on a different color cloth, a local Speaker DIY store sells some very nice silver/grey speaker cloth.
I'll let you know how it turned out.