Sansui squawker trade out

[Geoff_D]

Hi all, I have a bad S-106 “high squawker” in a Sansui SP-3500. It’s 12ohm 40watts, which I’m sure many of you know is an oddball to replace. If I am unable to locate an S-106, I am considering trying to physically adapt a Sansui tweeter of the same impedance and watt rating to stand in until I can find an original. What’s the worst that could happen?

 

[klipschorn]

If the replacement tweeter can handle frequencies above 2khz, there should not be a problem. The thing to consider is sensitivity. The S-106 has a sensitivity of 104dB, 1w1m. In the SP-3500 crossover, it is second order high pass filtered at 2khz.

A replacement tweeter may make the two systems sound noticeably different. That may or may not be a problem for you.





This figure shows the 1w1m on axis response of the SP-3500 with(red) the S106 horn and without(black) the S106 horn. An easy alternative would be to disconnect the working S106 in the other system. A slight increase of the treble control may satisfactorily compensate the high frequency response. At least the two systems will sound the same.

This response was measured with the system on the floor, which places a seated listener's ears about 30 degrees off the vertical axis when seated about 7 feet from the system.



The above data was acquired during a modification done in 2024 of a SP-3500 for an AK member who felt that the system was too bright for his liking.
There are two pages in my website regarding the above.

https://www.ln271828.net/sansui_driver_data.htm

https://www.ln271828.net/sansui_sp3500_odyssey_ADDENDUM.htm

Robert

 

[Geoff_D]

Robert, thank-you so much for your information filled reply! Sometimes the simplest solutions evade me! Disconnecting the working S-106 might be the short term solution!

The tweeter I’ve been looking at is a T-149 (“e” I believe), which is also 12ohm 40watt, but would require significant carving/remodeling to fit the same space as the S-106. I at least feel like I have options now! These are a rehab/restoration project I took on, and I got stuck looking for a replacement. Will start by disconnecting the one I have and seeing how much difference it makes! Best Regards -Geoff

 

[Sansuiman]

I'd be surprised if you can't find an S-106 with a bit of patience. Sansui sold tons of these (the SP-3500) back in the day, and parts routinely show up on eBay still. I'd avoid carving up the baffle place to mount an alternate driver. If I still had parts for these, I'd offer them to you. Regrettably, I unloaded the last of what I had for 3500's a couple of years ago.

 

[Geoff_D]

I'd be surprised if you can't find an S-106 with a bit of patience. Sansui sold tons of these (the SP-3500) back in the day, and parts routinely show up on eBay still. I'd avoid carving up the baffle place to mount an alternate driver. If I still had parts for these, I'd offer them to you. Regrettably, I unloaded the last of what I had for 3500's a couple of years ago.

I’ve found half a dozen in the past 6 months. Two sold before I could bid, two were sold along the entire mid/tweeter bank, another was available in the same complete bank, but I had to talk the seller through testing it, and it was the only driver out of five that was bad, and then one more that was offered for way too much $$$. I’m not positive, but I believe the S-106 may have been unique to the SP-3500, but I agree, eventually I’ll be in the right place at the right time!

 

[Sansuiman]

Yes, all the drivers on the 3500 are unique to other models in the series (which included 1200, 1700, 2500, 3500, 5500). If you are planning on keeping these long term, I'd heavily suggest buying a complete upper baffle with all the mids and tweeters mounted. That way you have spares for all of them. I've socked away spare drivers for most of my favorite Sansui speaker models, knowing that they will get more difficult and expensive to find in the future. One has to account for the possibility of amplifier malfunctions, simple age and environmental degradation, and even the occasional mistake of cranking the volume up too much, that can destroy these old drivers.


So, I try to keep at least one full set of confirmed working extra drivers per pair of a given model of anything I intend to keep. Granted, many of these spares were bought many years ago now, and I have actually used a few. Even now if I see a really good deal on a driver that fits one of my most prized speaker models, I'll usually grab it. And I've occasionally sold a spare to someone in a real jam.