Brand new factory Infinity Monitor II Walsh Tweeters

Beaglemaster

New Member
Not too long ago I was lucky enough to purchase two brand new, never used, Infinity Monitor II Walsh Tweeters in original factory Infinity shipping boxes, from a reputable eBay seller. Both tweeters are stamped 902-0033 on the bottom magnets and work fine. To my ears, both have approximately the same loudness level. However, one tweeter is clearly brighter than the other. I'd estimate a noticeable 4 to 5db brighter. I tested them on their own with the proper resistors, side by side, within inches of one another. I switched cables, used different amps, reversed left and right outputs, switched speakers, made sure to use a mono source, etc. and the excessive brightness always remains with that particular tweeter. There's no distortion in it, just a boosted treble.

I'd assume they should sound pretty much the same, so this is a bit disappointing. Does anyone have any insight as to what might be the reason for the noticeable difference in treble between the two tweeters? Is there a workaround to the problem that anyone could recommend?
 
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The tweeter is filled with foam. Foam degrades with time no matter how it's stored. It's possible that the interior foam has degraded differently in the two tweeters.
 
The tweeter is filled with foam. Foam degrades with time no matter how it's stored. It's possible that the interior foam has degraded differently in the two tweeters.

That sounds reasonable. However, from what I can see, the foam in both look about the same. Neither shows signs of degradation. I bought them as backups in case one (or both) of the Walsh tweeters in my IIA's conks out in the future. The foam of the new replacement pair looks even better than the foam in my still working original tweeters. Thanks!
 
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I don't have any Walsh tweeters, but is there any chance that some foam crumbs got into the voice coil gap?
 
I don't have any Walsh tweeters, but is there any chance that some foam crumbs got into the voice coil gap?

I guess anything's possible. I'll look into that in case I absolutely must take them apart.
I'm not looking forward to doing that. lol
Thanks!
 
Is there a possibility of a bad solder joint like on the QLS tweeters? I'm not sure how the Walsh are put together, so it may or may not be a possibility. Have you checked the ohm readings on both tweeters? I just got a pair of 409-125 tweeters today and they read 3.3 & 3.4 ohms. Sound great in my RS 2.5's.

Larry D.
 
As Larry mentioned his tweeters measured slightly different from one another.
Perhaps the OP might get a greater difference by measuring?
 
Is there a possibility of a bad solder joint like on the QLS tweeters? I'm not sure how the Walsh are put together, so it may or may not be a possibility. Have you checked the ohm readings on both tweeters? I just got a pair of 409-125 tweeters today and they read 3.3 & 3.4 ohms. Sound great in my RS 2.5's.

Larry D.

As of now I don't have a meter. Just doing it by ear, so far.
 
That original was 906-0060 you really should barely hear them except for tones over 10k why don't you try to subdue it with a little more poly. I have done so much experimenting with voice coils to get the same sound.
I bought 2 off ebay working. they were receive with cones smashed and one was off. trying to fine gold cone material and a super high freq voice coil. if you had the right voice coil there easy to repair.
 
That original was 906-0060 you really should barely hear them except for tones over 10k why don't you try to subdue it with a little more poly. I have done so much experimenting with voice coils to get the same sound.
I bought 2 off ebay working. they were receive with cones smashed and one was off. trying to fine gold cone material and a super high freq voice coil. if you had the right voice coil there easy to repair.

You said the originals were stamped 906-0060. I don't know what my originals are stamped because they're both still working and mounted in the IIA speaker enclosures. The ones I just purchased on eBay are stamped 902-0033. They were never used and packed in original Infinity boxes. They look exactly the same as the pair in my speakers except for the color. The one's I purchased on eBay are bright gold cones. They're approximately the shade of a beautiful gold coin. The ones in my speakers are a more subdued "goldish" tone. In 1974, before I owned the IIA's, I purchased the original Infinity Monitors and those cones were SILVER, not gold or "goldish". So that's three different shades I've seen so far. Would there be any other differences between the 906-0060 and 902-0033 series?

Regardless, concerning the replacement pair I just purchased, one tweeter is still brighter than the other. To make matters worse, my technical skills are limited and I'm afraid to mess with them. lol

I'm hoping that if I ever have to install them, maybe just turning back the rear mounted tweeter control on ONE of the speakers would balance them and make them sound the same?
Thanks!
 
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Never heard of the 902-0033 Walsh tweeter, only the 902-
0060.
Since there seems to be a 902-0066 Walsh, there is no reason to think that they would not sound "different"from the originals:dunno:
 
Never heard of the 902-0033 Walsh tweeter, only the 902-
0060.
Since there seems to be a 902-0066 Walsh, there is no reason to think that they would not sound "different"from the originals:dunno:

Photo of the Walsh tweeter stamped 902-0033 on bottom magnet.
Infinity Monitor II Walsh Tweeters.jpg
 
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Photo of the Walsh tweeter stamped 902-0033 on bottom magnet.
View attachment 1151002

From the original eBay ad quoted below..........
View attachment 1151065
INFINITY ICE CREAM CONE TWEETERS 902-0033 NEW OLD STOCK

THESE TWEETERS WERE PURCHASED FROM INFINITY, AS YOU SEE THEM , FOR A REPLACEMENT BUT WERE NEVER USED.

THE FOAM IS IN GOOD CONDITION , THE GOLD CONES HAVE SOME DENTS ( SEE PHOTOS ) BUT THIS DOES NOT AFFECT FUNCTION .

AS YOU CAN SEE THEY HAVE AN ADDITIONAL MOUNTING RING THAT COMES WITH THEM FOR MOUNTING IN DIFFERENT SPEAKERS.

WARNING THESE ARE VERY DELICATE TWEETERS AND NEED TO BE INSTALLED BY A PROFESSIONAL !!!!! SOME MODIFICATION MAY BE NEEDED !!!!!

PLEASE VIEW ALL PHOTOS THESE ARE THE ONLY NOS REPLACEMENTS FROM INFINITY AND ARE NO LONGER AVAILABLE .

SOLD AS A PAIR . FOR THESE SPEAKERS :
WTLC - Wave Transmission Line Column
2000 AXT
2000 II
MONITOR
MONITOR IIA
 
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Well, since we are not seeing an electrical difference there must be a mechanical or construction difference. I wonder if these are ferrofluid damped and maybe one has no ferrofluid and the other does. Beyond that I have no other ideas of why they should sound different.

Larry D.
 
Hey Beaglemaster, my bet is if you placed them in the circuit of the speakers they would sound the same. They are very rare for sure, nice looking pair, maybe the nicest anywhere. Good luck.
Jim
 
Hey Beaglemaster, my bet is if you placed them in the circuit of the speakers they would sound the same. Jim

That's good news! Since my originals still work, I only tested them coming from the the L-R outputs from my amp with the proper resisistors. They test fine and sound smooth, but there's just that noticeable difference in treble.

I'm not arguing, but just curious as to why placing them in the circuit of the actual speakers would make them sound the same? Since I'm not very "tech savvy", I'm trying to learn what's going on.
Thanks Jim!
 
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