Re: [AH] Acoustics question: speaker resonance

From Brian Willoughby
Sent Sat, Feb 16th 2019, 06:40

I think your best bet is to just get rid of these speakers and find some =
different ones that don=E2=80=99t have any problems that need fixing.

I had a similar problem with some B&W speakers. The plastic back plates =
would buzz at a certain frequency. The funny thing is that I never =
recall hearing them buzz with rock or jazz music, but when I played =
synthesizer music - a particular Robert Rich CD - they would reliably =
buzz. There were a couple of other CDs that would show the issue. I =
ended up selling them used. In fact, I had inherited them basically new =
from a girlfriend who didn=E2=80=99t like how =E2=80=9Cbright=E2=80=9D =
(accurate) they sounded. They were about $300 each.

This is when I learned that the easy part is making a driver that =
produces all of the right sounds. The hard part is an enclosure that =
doesn=E2=80=99t detract from the sound by buzzing, resonating, or =
otherwise coloring the sound. I suspect that as a beginner you might =
have a hard time perfecting those speakers if the original manufacturer =
couldn=E2=80=99t do any better.

I ended up with Linn Tukan speakers. Those were about $400 each, and =
I=E2=80=99ve only ever heard good sounds come out of them. No resonances =
or unwanted vibrations. That company really knows speakers. I have three =
pair now (stereo plus surround).

Another good option when I was on more of a budget was the Paradigm =
Titan v5. I paid less than $200 a piece for those. Bigger, more bass, =
maybe not as smooth as the Linn, though. I had four pair of these, but =
three pair were stolen from a storage unit before I could build out my =
next multichannel surround project.

Brian


On Feb 15, 2019, at 12:17 PM, Royce Lee <xxxxxxxxxx@xxxxx.xxx> wrote:
> Just to make my life more difficult, I've decided to impose a =
challenge to myself by switching from studio monitors to home hi-fi =
speakers. I've been through a series of mid range studio monitors and =
have concluded that while they have some advantages, they are butt ugly =
and don't seem to sound that great until you get into the >1000 range. =
While I have the means to go there, I'd just rather not.
>=20
> Within this limitation, and a further self imposed limitation of =
assembling a system costing less that $200, I've settled through trial =
and error on a pair of Mission 761i speakers I bought on ebay for  $60 =
that arrived with broken cabinets and a $75 Micca stereo amp. It all =
kind of works because of a subwoofer, by which I mean when I play =
program material the stereo imaging is great (better than before). I'm =
sure there are some real problems with my room and system, but I'm =
determined to put up with these for at least the next moment.
>=20
> Here is the challenge: I'm pretty sure that around B3 Bflat3 I have =
some kind of resonance problem. So not the B below middle C but the one =
below that.
>=20
> I've tried looking at frequency tables and matching up wavelength but =
have not had any success figuring anything out. The speakers are 380mm =
tall. I believe that the resonant behavior is not determined by the =
stand (the same thing is going on when I try them in a different room =
with different stand). I believe that the resonance is related to a good =
thing: these speakers don't have a scooped middle and have a healthy mid =
range presence.