Help selecting mid bass driver replacements

Hi
I'm a complete novice when it comes to this stuff so go easy on the nooB!

Speakers: Mission m64i
Problem: one blown mid bass driver LF-M049, 8ohm, 168mm OD, 140mm cutout.

I am having great difficulty finding a replacement because the baffle cutout diameter is 140mm, which is slightly too small for the normal 6.5" driver options. There's no info available for this driver using the search term LF-M049 as per the sticker on the magnet. It looks just like a regular Monacor driver, but they don't have one that's the right size for the baffle cutout.

However I've found a Peerless driver - SBS-160F35AL01-04 - this fits but I don't know if it is the right spec.

What sensitivity should I be using? Most of the woofers seem to be around 84-09 dB but these Peerless ones are 78.7 dB. So I haven't the foggiest if they would sound ok and match the crossovers.

Like I day - completely ignorant about this stuff! But am an engineer (mech) and love getting into new stuff, so feel free to educate me.

Any guidance on what to go for in terms of audio specs would be greatly appreciated. I'd replace both drivers obviously.

Amp is a Cyrus III with PSX.
 
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Try a replacement with similar construction. If it's not sensitive enough, use the crossover to reduce the tweeter level. There will obviously be a limit for the tweeter going the other way.

You'll need to study the crossover.

Later you can tweak the woofer crossover. You might measure it. You might make comparisons to the working unit.
 
Member
Joined 2005
Paid Member
That SBS-160F35AL01-04 is a small woofer: and by no means midwoofer suitable for matching to a tweeter.
852789C1-3950-440C-ADBA-BE6841F7584E.jpeg



Sensitivity differences aside; the droop in the midrange will make it unsuitable for a replacement.

Exactly what is blown with existing midwoofer?
 
Hi
I'm a complete novice when it comes to this stuff so go easy on the nooB!

Speakers: Mission m64i
Problem: one blown mid bass driver LF-M049, 8ohm, 168mm OD, 140mm cutout.

I am having great difficulty finding a replacement because the baffle cutout diameter is 140mm, which is slightly too small for the normal 6.5" driver options. There's no info available for this driver using the search term LF-M049 as per the sticker on the magnet. It looks just like a regular Monacor driver, but they don't have one that's the right size for the baffle cutout.

However I've found a Peerless driver - SBS-160F35AL01-04 - this fits but I don't know if it is the right spec.

What sensitivity should I be using? Most of the woofers seem to be around 84-09 dB but these Peerless ones are 78.7 dB. So I haven't the foggiest if they would sound ok and match the crossovers.

Like I day - completely ignorant about this stuff! But am an engineer (mech) and love getting into new stuff, so feel free to educate me.

Any guidance on what to go for in terms of audio specs would be greatly appreciated. I'd replace both drivers obviously.

Amp is a Cyrus III with PSX.
I would ask Mr. Lommersum - great knowledge also concerning Peerless and Vifa.
ASE - Acoustic Systems Engineering
Dipl.-Ing. (FH) Gerd Lommersum
Scan Speak - Vertrieb
Lerchenstrasse 9
D-72336 Balingen-Erzingen
http://www.ase-scanspeak.de

In the attachment a test review with images of the used driver
 

Attachments

  • Mission M6i review.pdf
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G'day,

If you are Auckland based you can try Axent Audio in New Lynn.
They seem to be a great source of "truth" plus they know where to source parts from etc and guidance if you want to do it yourself.

And, if you give up....they'll sort it for you!

Cheers
 
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Unfortunately the Axent guy is dead.

So unless I post the driver to St Peter, it’s probably going to go unrepaired.

I would still quite like to get it repaired because four floor standers in the shed plus the sub would be just great.

[whilst reading up about Axent it did seem like a bit of a lottery as to whether or not you would get your repaired driver back in a couple of days or several years. Some very mixed reviews!]
 
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"one" Axent guy passed away. Not too sure if he was "the" guy.
I assume they're still in business and accepting gear for repair....I sincerely hope they are!

I've had 4-5 repairs done over the last 10-15 years and can say 2 things about the service...
1) They've done an excellent and thorough job
2) They've always offered competitive prices and often below what I'd expect

Yes, they can sometimes be slow and it does depend on how much work they have on, how complex the repair is and lastly availability of parts. They DO have one of the biggest collection of speaker spares in NZ!

The longest I've ever had to wait to get my gear back was 5 weeks. The shortest was 1 week.
Quote turnaround is usually only a couple days and they usually give an indication of ETA for repair.
(I am not affiliated with them at all BTW)
If you are Auckland based and they're still in business, go pay them a visit....not your typical hi-fi shop, that is for sure! You will not be disappointed...so much 2nd hand gear on offer.
 
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Well fortunately I go to Auckland about once every five years, and generally only to the airport. Avoid the place like the plague! We’re remote rural in the CNI.

But it’s definitely peaked my interest this place and if I do find myself in Auckland any time in the next few years I’ll take a look. I’m very curious about the stories I’ve been hearing about the incredible collection of older hi-fi gear which is quite appealing.

It seems it’s a walk in only type joint as there’s no phone / voicemail / website. Just a message pointing you towards an email address which according to reviews may or may not get answered.

Thanks for your tip about the other guy, I will give him a call and see what he says.