New to Altec, Model 14's with 902's

[Tozco]

Hi,
I have always been interested in scoring some Altecs for my livingroom. So I jumped on a set of model 14's with the 12" LF and 902HF with Mantaray horn. I'm using C-J MV-45 EL-34 strapped triode amp for the power. The Altecs sound large and dynamic but are shrill and harsh with female voices and applause. A sax can sound almost like a kazoo. My wife was actually compelled to leave the room. Now I am very familiar with horns because my referance speakers are Klipschorns I have had for 10 years. The Khorns are as smooth as can be with the same upstream components. Any thoughts on what might be wrong or what I may change to tame the 902's a bit?
I did test the overload circuits by pressing the buttons when playing at a decent level and they do light. I also checked the phase to the LF to make sure I was getting all I could on the low end. The bass is there when the program material calls for it and it is non intrusive the rest of the time. But boy are the voices shrill. I have listened to a few A7 and Valencia type set ups and have never experienced this kind of trouble. Thanks, Mike

[MikeInNH]

I am far from being an expert. But since you bought the speakers used and they are several years old, they might NOT have the origional diaphrams or even OEM diaphrams for that matter.

I've never had that experience with ANY Altec speaker I've owned or used. The only time I ever heard any shrilling from a Horn speaker was with a pair of JBL's using a Titanium diaphram. The person who owned the JBL's replaced the Titanium diaphrams with Aluminum ones about a year later. They sounded MUCH better.

Good Luck....Hopefully someone with a lot more experience and expertise will be able to help you out better then I could.

[Todd W. White]

Oftentimes, people complain when they first get an Altec speaker, because they paint the audio picture "warts and all." What I mean by that is this: if your ears have become acclimated to the way an inferior speaker system reproduces sound, then you get your Altec's, the tendency will be to perceive that the Altec's sound harsh, when in reality you are actually hearing all of the sound that is really there, except you never heard it before, so your ears are "prejudiced" against accurate sound reproduction, and in favor of inaccurate reproduction.

If this is not the case in your curcumstance, then I would check my electronics to make sure that they are operating properly. Check the outputs of the amplifiers with an oscilloscope. Look at the audio signal for distortion, check your grounding scheme, etc.

If you find that your equipment is functioning properly, then there is something wrong with your Model 14's.

In that case, I would suggest:

1. The high-frequency diaphragms have been replaced with inferior non-Altec clones.

2. The high-frequency diaphragms have been damaged. This is usually unlikely, though, because the Model 14 has a passive crossover with a fairly sophisticated speaker protection circuit built into it.

Take your crossovers out and examine them - are they clean looking? Are there any signs of arcing in the L-pads or on the pc board? Do they smell burned?

Let me know the condition of the crossovers, then we'll get into the speakers themselves.

[Tozco]

Thanks for the replies regarding these Model 14's.
I see that you both suspect diaphrams might not be original. To answer Todd, I am familiar with what these speakers should sound like. Also my upstream components are up to task. I have been steadily upgrading with great results because my regular speakers are K-horns which are quite revealing and can sound harsh with poor components or program material. The point is the Klipsch sound is usually considered harsher than the Altec sound. Why do my New to me Model 14's sound so shrill when compared to the K's?
So we must conclude there is some fault that needs to be rectified.
The X-overs looked pristine. The L-pads look and work fine. The protection circuits also work fine.
I guess checking the diaphrams is next.
Not sure how to proceed.
Thanks Gentlemen, Mike

[Tozco]

I think I am back on track. I did get around to checking the diaphrams and they looked perfect and have the same number that is referenced at Great Plains. What I did notice was that some of the screws holding them on were loose as where all of the components to the motor board. So after torqeing the components down carefully the sound became more balanced. I believe I am getting used to the sound and liking these more and more. Thanks again for the above suggestions.
Mike

[Todd W. White]

If you still find they are not sounding right, CAREFULLY remove the diaphragms and make sure the TANGERINE radial phase plug hasn't come unglued - some of the early ones did, and BOY! do they sound BAD when they do!

[Tozco]

Wow, sometimes it's the simple things that cause the problem. As I mentioned in an earlier post, I was getting used to these Model 14's and liking them more and more. But there was something wrong I just could not put my finger on. A lack of warmth or balance or something. Well I had checked the phase of the LF drivers to one another but I neglected to check if they were phased correctly to the system. As it turned out the previous owner had the drivers reconed and installed them with the black lead to pos and green lead to neg. I guess he thought green was ground but this is not the case after studying the crossover. So I corrected the wiring.
Anyway to say that the sound is more cohesive and balanced is an understatement. I love these speakers, they pack a punch for the size.
Thanks to all and as time allows I may search for some Valencias or 19's.
Mike