Replacement for Seas 11-fm driver - Please help!


2013-03-08 8:57 pm
Hi everyone,

Please help! My son has just damaged my Seas 11-fm driver beyond repair. The speakers were given to me by my dad and i'm obviously keen to replace the drivers and get the speakers working again.

The Seas 11-fm is no longer available and i've only managed to find a couple of possible alternatives:

1)Audex HM100z0
2)Monacor MSH 115

Which of the drivers is better? The audex requires a resistor as its more sensitive than the original whilst the Monacor is virtually identical to the original and is a straight swap.

Alternatively can anyone recommend a better alternative? The driver cannot be any larger than 4"/110mm as there's no room on the cabinet.

The Audex is around £70 per driver whilst the Monacor is about £35. I cant really go beyond £70 per driver and anything less would be good!

Many, many thanks in advance Phil.

The best matching driver is always a better bet
than something more exotic that costs more but
is less likely to work well with the other bits IMO.

Sometimes it does, most of the time it doesn't.

Some people think its an opportunity to make
speakers better, IMO replacing drivers is a
damage limitation exercise, only rarely can
the replacements be better, (except for very
naff speakers in the first place), and IMO its
get as near to the original driver as possible.

Statistically its the the most likely best option.

rgds, sreten.
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The 11FM is ancient, from the 70s. The only stuff of any real interest is that it's 89dB sensitive, has a free air resonance of 150Hz and apparently came in 4, 8 an 15ohms.

From what I can see, from a quick google, the MCA11FC is almost a drop in replacement, SEAS say as much in the 11FCs datasheet.

It is possible that with a bit of searching around and possibly phoning up loudspeaker distributors, that you might be able to find a pair of those, as they weren't discontinued that long ago. The current MCA12RC is not suitable in any which way really, which is unfortunate.

Going by the MCA11FC though, it has a very flat, extended and well controlled frequency response at the extremes. It is reasonable to assume that this was taken full advantage of in your loudspeaker, which makes finding replacements difficult.