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So I picked a good-looking set of speakers up at a thrift shop for 5 bucks (Aiwa SX-LM99). Can't find much on them on the internet but they appear to be working fine. I tested them at a friend's place who had a proper speaker pre-amp and stuff. Connecting them to my own setup, however, posed some issues. If I run a frequency sweep, they spike at around 180 Hz (very noticable when listening to music) and a couple HZs before that, the sound seems to pan around (first it seems as if i hear it left, then right, then left, then back to center as it should.) Any idea what's going on here? Will it be fixed if I get another speaker pre-amp? I'm currently using my turntable, perhaps that's adding some sort of EQ to compensate for the low end's in records? That's just speculation though. I'm sorry if I'm not very clear. Thanks for any help!

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Boswell Sun, 09/27/2015 - 15:02

These are cheap speakers, irrespective of what you paid for them.

From your sweep testing, it sounds as though the design has a resonance in the 170 - 190 Hz range, but because of poor production control, the resonance does not occur at the same frequency in a supposedly matched stereo pair, so what you are hearing is the effect of two resonances at slightly different frequencies. Your room is probably accentuating the resonance, whereas your friend's is not.

pcrecord Sun, 09/27/2015 - 15:51

Nisse, post: 432676, member: 49036 wrote: Will it be fixed if I get another speaker pre-amp?

The term is amplifier, which does amplify the signal for the speaker to move and create sound.
A preamplifier is a unit that will get a microphone's signal to a record level (which is far less than what a speaker needs)

You could EQ the problematic frequencies before the amp. But getting a flatter speaker will do better goods.
Technology has advance very much in the last decade. You can get very usable studio monitors for 300$ a piece and more. Yamaha, KRK and others..

DonnyThompson Mon, 09/28/2015 - 04:40

Nisse, post: 432676, member: 49036 wrote: So I picked a good-looking set of speakers

Visual appearances matter very little when the primary function of the device is audio.
It wouldn't matter if they were mahogany, black walnut, or dipped in 24 ct. gold for that matter... if the speakers are cheap, and the cabinet design and construction is haphazard, then it doesn't matter how "good looking" they are.

By and large, you generally get a level of quality that is commensurate with what you pay.

Taking shortcuts in this craft will ultimately result in faults that become apparent - and quite often in glaring ways. You've just experienced this yourself.

But take heart - you're only out 5 bucks. It could have been worse... a lot worse. Consider that five dollars to be a very cheap - but effective - educational experience.

I suggest that you do some research on audio and loudspeaker systems. No offense, but it's your ignorance in the field which led you to make a poor purchase decision.

I would add that the next time you find something you are interested in buying, perhaps it would be better for you if you posted your questions here first... before you open your wallet.

-d.

DonnyThompson Mon, 09/28/2015 - 08:41

bouldersound, post: 432696, member: 38959 wrote: But I still think it's an acoustic thing in the room, something to do with the rear ports and placement relative to walls or other boundaries.

I agree... it's certainly not impossible, in fact it's highly probable.

But, if on top of that, he's also dealing with cheap speakers/cabinets that have inherent issues due to poor design, cheap construction, and which present resonant "wizzlies" ( a term that I'm sure Brien ( @Brien Holcombe ) would determine as being most assuredly non technical in nature, LOL) - then the possible room issues are that much more pronounced; as opposed to using a pair of speakers/enclosures that were well-designed, matched, properly tuned/ported and otherwise well-built.

So in short, yes... the room matters, I don't think anyone would (or could) argue that. But using garbage speakers/enclosures for (accurate) monitoring purposes certainly isn't helping that situation in any way.

pcrecord Mon, 09/28/2015 - 09:17

bouldersound, post: 432696, member: 38959 wrote: I agree with all that about cheap speakers. But I still think it's an acoustic thing in the room, something to do with the rear ports and placement relative to walls or other boundaries.

That's something to be investigated. Maybe the speakers are excellent but the placement make them lie... rear ports are very picky on wall distances..

paulears Mon, 09/28/2015 - 15:31

These kinds of ported speakers aren't designed to sound remotely flat, the port tuning picked to give an exaggerated bass response from a small box, with all the problems that introduces on the quality front. I'd bet it's an unhappy accident of some of the room nodes aligning with the peaky speaker response. The test would be to take them outside and see what they sound like without any walls. In fact, if you don't mind annoying the neighbours, a pink noise test, with the resultant audio recorded, and the same again with a 20-20KHz sweep would be useful, as you could then do the same test again inside, and compare the results.

OBrien Mon, 09/28/2015 - 16:33

bouldersound, post: 432696, member: 38959 wrote: I agree with all that about cheap speakers. But I still think it's an acoustic thing in the room, something to do with the rear ports and placement relative to walls or other boundaries.

It's always the room...but you need real speakers to define that. Crap can exist in a crap room and everyone is happy. Bring a set of $800.00 monitors in there and the speakers will reveal the damage the room is doing to the speaker response.

The poster never mentioned the term "rear port" so that on going argument is a waste of time. But I would ask that you all take a look at the speakers in question. Google it. You will come to your on conclusion that, yes, they are dirt cheap, and no, a better sounding room is not gonna help.

OBrien Mon, 09/28/2015 - 19:20

paulears, post: 432721, member: 47782 wrote: Brien, why do you keep asking yourself questions?

Because AIWA is making a come back, I am just giddy with excitement!

[[url=http://[/URL]="http://recording.or…"]Nisse[/]="http://recording.or…"]Nisse[/],
We want you to do good but you understand that everything matters and the speakers you picked up are not designed to do what you are asking them to do. Many here do professional work in the field of audio. I personally do not, but when I was involved I bought an $800.00 pair of Tannoy monitors. Still have them in the closet right under my dirty books :) Get yer head out of the gutter...lotta dust in there.

Ya gotta find a way to finance yer G.A.S. when you are chasing the dream!