A Speaker Doozy!!

[Aman]

This is the wierdest thing I've ever experienced!

I have this speaker setup... a Pioneer SX-450 ---> Ohm Model B speakers

Both of these devices are old (from '76) but both are highly acclaimed.

So if the speakers are plugged in the correct way, the left speaker hardly plays anything at all .. but what sound it DOES play, it plays cleanly.

So I switched the cables today -- and noticed that the speakers now play balanced and even. BUT .. this same left speaker (which is now actually outputting the right-channel sound) distorts on many higher pitched notes coming from the tweeter!

I don't quite understand what is wrong here. I thought it was just a speaker problem, but now the speaker acts completely different when hooked up to the opposite channel.

But if this were an amplifier case, wouldn't the right side speaker play the sound like the left speaker would if it were hooked up correctly? The right speaker when playing from the left channel plays cleanly and balanced!

No, I am not deaf in one ear, since my brother and my friend both confirmed these exact same findings when they listened. They automatically knew what was the matter, and when I changed it they said it was much better. They said it was more balanced and they could hear the details again.

What is going on here? Are my speakers dead? Is my amp dead? Are they BOTH dead??

I'm very confused here!!
-Andrew

 

[rickcr42]

Started to lose me there A-Man.I think maybe the last two hours in the DIY forum has fried my brains but i would google the speakers to see if I could find out if there is a speaker protection circuit in the crossover.This sounds like the classic "circuit gone south" scenario that sometimes you get with vintage speakers.

My guess off hand is that something crossover/protection related is polaying hell with the receiver protection cisuits by shorting the outputs intermiitantly.

Is the the Walsh Tweeter version ? the one with the "ice cream cone" tweeter ?

 

[Aman]

http://ohmspeakers.com/store_item_de...ID=58102352739
Those are the speakers.

Thanks rick!
-Andrew
PS: I can't find any information on this speaker accept from ohm's website due to the name of the speaker:

"ohm b" - search results pop up that aren't the least bit related to the speaker itself.

Oy vay!

 

[Snake]

Quote:

Originally Posted by Aman So I switched the cables today -- and noticed that the speakers now play balanced and even. BUT .. this same left speaker (which is now actually outputting the right-channel sound) distorts on many higher pitched notes coming from the tweeter!

But you don't say if they play "balanced and even" at EXACTLY the same level as the right (ONLY) channel did before switching or (both) now play at a reduced volume to balance out (say, the level of the previous left channel).

It sounds like you have one bad channel on the amp and 1 bad speaker / driver.

 

[Aman]

That's true. I just tried switching the left speaker's cable with both the right and left channels, and seeing if I can hear a difference in volume. Surely enough, I can't.

So are you saying that because the channels are reversed it's doing some strange voodoo to make me perceive the sound differently?

I'm going to actually physically move the speakers to their opposite positions to see what that will do.

Thanks!
-Andrew

 

[rickcr42]

Quote:

It sounds like you have one bad channel on the amp and 1 bad speaker driver.

Always possibel but MAN ! do you know what the odds of that are ?

Unless of course the speaker damaged the amp or the amp the speaker if that makes any sense.i am a bit loopy from posting tonight

A-Man,gonna check a couple of "my stash" links to see what i can dig up dude.Sit tight but if i am not back soon don't wait up honey

 

[Aman]

Woah!

I just physically moved the speakers to their opposite positions (so that the channels are now not reversed, but outputting the left on the left speaker, and the right on the right speaker.

Now the left speaker is outputting the most and the right speaker is hardly audible!

So is it a speaker problem then, or an amplifier? This is very wierd.

 

[rickcr42]

sounds like a loose or dirty connection if it changes so dramatically with each move.Any contact cleaner handy ?

also do a visual inspection of both the speaker and amp connectors then with the aMP OFF give the connectors the "wiggle test" to check for connector integrity.If none of these things are the cause it may just be a bad match trigerring the amp protection circuits in a random way.

Those puppies may be small but the load on an amp is NASTY !

89dB @ 4 ohms will stress many amps not suited for driving a four ohm load and many can not beleive me.

Last resort is to eliminate either the amp or the speakers as the culprit by swapping in either another set of speakers to the amp or the speakers to another amp.test at LOW volumes only until you are sure all is well.

hope this helps man

 

[ooheadsoo]

They're actually 86db sensitive. Even worse...

 

[rickcr42]

told ya I was loopy from way too much screen time today.I actually thought I wrote 86 and not 89

 

[Snake]

From here I'll agree with Rick - check those cables man. Also check the binding posts of the amp - older amp's binding posts can weaken / loosen internally and your fooling around with the speaker wires is intermittantly changing those weak connections. Happened before.

 

[Aman]

This is wierd!

I just hooked the speakers up again, with the left speaker taking the left signal, and the right speaker taking the right signal.

It's balanced again.

I don't know what happened! It just started working beautifully.

I'm going to test to see if the tweeter is still acting funny.

Thanks again for all the help!
-Andrew

 

[ooheadsoo]

Yeah, good idea. Might want to dig inside the speaker and make sure all the connections are still sound. I think ohm makes full range speakers with super tweeter, so there may not be a xover for you to worry about.

 

[rickcr42]

Quote:

I don't know what happened! It just started working beautifully.

i agree.no doubt now you have either a loose connection or a dirty one requiring a contact cleaner.Always a good idea with anything vintage audio to remove years of crud and oxidising on the contacts,none of which were gold back then unlesss you had a Mark Levinson with gold Camacs

 

[Aman]

Well the speaker that USED to be on the left (which is now on the right) does still distort higher frequencies. Different cables, all cleaned and such -- I think this one particular speaker is just bad.

Besides that, the channeling and balance seems okay.

I don't have the newest of the Ohm's - they're VERY old and they definitely have a crossover.

I have been in the speaker market for a while anyway, just because I want some better sound. I actually wanted to get other Ohm speakers - the Microwalsh Talls. I called John <last name forgotten> of Ohm Acoustics and they said that if my receiver ran the Ohm B's fine (which they do .. they can go to deafening levels!) then it should run the Ohm MW Talls better. Is this an accurate statement?

I may even be able to send the old speakers in for 25 percent off .. now that's a deal!

Thanks for all the help guys!
-Andrew