Newbie Building a Lyra

[ingvar ahlberg]

Good, the DIY audio workshop realy is a hard hat area.

[Kofi Annan]

If anyone's interested, I had to send away for another midrange. I was getting some distortion and I originally thought it was due to an underpowered IGC amplifier. When I finally got off my lazy *** to investigate the issue, I discovered that it was the midrange in the left channel speaker that was at fault.

I sent away for another one from Parts Express, but I'm wondering how that could have happened. I took the speaker apart and I didn't notice any problems-- although I'm not sure what to look for.

When it plays, the midrange sounds like garbled distortion, although you can still hear the sounds somewhat. I'm wondering if I could have blown the speaker through mishandling it or if it could be a factory defect.

Anyone else ever had a similar problem? Any ideas why this went wrong?

Kofi

[Sherman]

Originally posted by Kofi Annan
...I was getting some distortion... I discovered that it was the midrange in the left channel speaker that was at fault.

.. I took the speaker apart and I didn't notice any problems-- although I'm not sure what to look for.

Kofi

If the cone doesn't have a tear in it and the surround is intact then my guess is a damaged motor. The speaker may have been dropped and landed on the motor casing. No visible damage but now there is damage which may cause rubbing or jamming of the moving parts inside the motor casing.

It could also be something as "simple" as a bad lead with poor contact either at the terminal connection or at the motor.

In either case get a new one.

Sherman

[Kofi Annan]

If the cone doesn't have a tear in it and the surround is intact then my guess is a damaged motor

That would make sense since I didn't notice any other problems.

In either case get a new one.

Yep, that's what I thought. Got one on the way from Parts Express.

Oh well, I guess I can't be too disappointed. These speakers actually sound great even with the distortion, but its driving me nuts so its gotta go.

Thanks for the advice.

Kofi

[ingvar ahlberg]

Exchange midrange units between speakers to make shure there´s no problem in the filter, if distortion follows driver then likely Sherman´s right ,rubbing in voicecoil, probably due to careless handling in transportation. If distortion stays in the same cabinet, check filter.

[tiagor]

Hi,

follow Ingvar's advice and check the problem isn't in the crossover.
You'd also probably benifit in reducing the (physical) size of the crossover. Make the connection wires shorter(better yet, solder the component leads together where possible).



Good luck with the new speakers.

Regards,

Tiago

Besides, I'm the Secretary General of the United Nations NOT the head of the US State Department-- I can't pull strings on the visas and I ain't got the coin to get folks from India to NYC-- I can't even afford real dampening material!

Perhaps it's time to add audio diy to your Curriculum Vitae and ask for some research funding

[Kofi Annan]

Thanks for the advice! I already checked the crossover and its fine. The speaker is distorting when I use it in my other stereo, so I feel prety confident that its the problem.

Yeah, I realize that I should have built the crossover more compact, but its really in the speaker good now, so I hesitiate to remove it. I sealed it in the speaker, so it woud be a real motherfather to get out. Just stupid on my part.

I'll let you know what happens when I get the new midrange in.

Kofi

[Kofi Annan]

Hey-- the bass in my speakers is causing rattle and distortion on certin bass frequencies. Not bad, but enough to drive you crazy once you hear it.

Multiple Chioce Question--

Do I need:

(a) more stuffing?
(b) less stuffing?
(c) better isolation from the hardwood floor?
(d) a new hobby?
(e) other (please explain)

_______________________________________________

Kofi

[ingvar ahlberg]

Does the "rattle" come from driver? If so check cabinet for leaks, mating surfaces between drivers and cabinet are often hard to keep airtight. Use selfadhesive rubber/foam or silicone windowsealers.
If rattling comes from something else excited by wibrations, try isolating speakers from floor and see what happens.

[ingvar ahlberg]

Rattling could also come from the filter "board" as it is fairly large it could vibrate against cabinet if not tightly screwed down. Internal wire could come into contact with speakercone at large excursions also making noices.