How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Russell H. Your Own Question
Russell H.
Russell H., Service Tech
Category: Consumer Electronics
Satisfied Customers: 10919
Experience:  8+ years of professional experience
Type Your Consumer Electronics Question Here...
Russell H. is online now
A new question is answered every 9 seconds

I have a pair of Sansui S-107 horn midrange. They work fine,

Customer Question

I have a pair of Sansui S-107 horn midrange.
They work fine, but I can't find any information on minimum recommended crossover frequency.
Also, are they likely to keep working?
I plan to drive them with a 7 watt 300B amp, but don't wish to redo my project if the driver fails, as these parts are rare.
Any advice is much appreciated.
Submitted: 1 year ago.
Category: Consumer Electronics
Expert:  Russell H. replied 1 year ago.

Hi, thank you for contacting My name is Russell. I will do my best to provide the right answer to your question.

Crossover frequency depends upon not just one speaker set, but also on the other speaker or speaker set that is nearest to it in frequency range.

*Minimum* crossover frequency, for really subwoofer-type sound production, would depend upon how much wattage you are trying to get the subs to produce.

Overdriving the wattage of the speakers, or the subwoofers, will reduce their lifetime for sure.

If the S-107s were from a Sansui S3500, then the ratings for wattage output of the S3500 might indicate the wattage ratings for the S-107s. Does that sound reasonable?

Customer: replied 1 year ago.
The power rating for the S-107 compression driver is 10 watts, 16 ohms.
Minimum crossover frequency has nothing to do with other drivers.
It is typically 3 octaves above the drivers impedance spike.
Applying maximum rated power below the recommended crossover frequency will cause the diaphragm to crackerjack, shatter, and fail.
The answer didn't provide any information relevant to the question, which was - what is the recommended minimum crossover frequency.
I have made and sold dozens of speakers the last several years, but always with the Thiel Small parameters available to me.
I stated, I was seeking the minimum recommended crossover frequency, what should have asked , is what frequency is this driver's impedance spike at; then I can guess where a safe crossover point is to operate the driver at.
I was hoping you may have information germain to the equipment I do not, but it seems this is not the case.
Thanks anyways.
Expert:  Russell H. replied 1 year ago.

I do not have that specific information, and must apologize for my having disappointed you.

To make things fair, I have Opted Out of this case, opening it to the Expert in this category who might have that specific information on the speaker horn's specifications.

Customer: replied 1 year ago.
Thanks, ***** ***** bad feelings on my end.