I've been given a pair of National SB-105H speakers. They are in immaculate condition despite their age, However I have no idea how to connect them! They have a 4-way connector and I have a stereo amp. Help!
Hi,
Two of the connections go to the MFB 'sensor' which I believe is a separate coil in the woofer. The other two go to the crossover and then speakers as per the usual setup. So you need to work out which two are the speaker connections. You COULD probably just try a low power signal to the terminals and see which produces sound.
However, I recently read something that might assist (if you have good eyes!). If you look at Post 72 on this page, there is a photo of the schematic of the internals of those speakers. It's not easy to see but with suitable zooming you might be able to work it out.
Note I'd seen this page before as there were a pair for sale on Stereonet and I'd done some research, as I have a Philips MFB preamp. It was in my bookmarks...normally I wouldn't remember!
Cheers
Stuey
Two of the connections go to the MFB 'sensor' which I believe is a separate coil in the woofer. The other two go to the crossover and then speakers as per the usual setup. So you need to work out which two are the speaker connections. You COULD probably just try a low power signal to the terminals and see which produces sound.
However, I recently read something that might assist (if you have good eyes!). If you look at Post 72 on this page, there is a photo of the schematic of the internals of those speakers. It's not easy to see but with suitable zooming you might be able to work it out.
Note I'd seen this page before as there were a pair for sale on Stereonet and I'd done some research, as I have a Philips MFB preamp. It was in my bookmarks...normally I wouldn't remember!
Cheers
Stuey
https://www.kevinchant.com/uploads/7/1/0/8/7108231/sb-105h.pdf
Someone was kind enough to upload the SB-105H crossover schematic.
I looked at the amplifier/tuner that would've come with these speakers originally, but nothing special stood out regarding speaker outputs (SA-52H valve amplifier).
Someone was kind enough to upload the SB-105H crossover schematic.
I looked at the amplifier/tuner that would've come with these speakers originally, but nothing special stood out regarding speaker outputs (SA-52H valve amplifier).
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