Realistic Optimus 9- has anybody actually heard these??

[Adam S]

Hello AK, so these popped up for sale about a 1/2 mile from me for what I consider a very fair price so I started researching them (you know the drill) but can't find much info out there, even on here. Here's what I've found; These were top- line in '75 with 12" rubber surround , cast frame woofer, same as the great Optimus 5, 3 mids, dome tweeter and walnut veneer cabs AND these are in excellent shape. BUT what concerns me is the wacky cab design. These are only 9" deep but 28" tall and 19" wide. Also I read they have a 1/2" slot on the top rear behind the 3 mids for "360 midfield sound radiance" -seems odd and another guy speculated the woofer chamber is sealed off from this "port" so they may be low effiency with a funky bass character as some RS speakers were. Any info would be appreciated!

 

[Adam S]

Some pics....

 

[Stuart Pedaso]

Optimus 9 was listed for 1974 and 1975 only. That would suggest relatively few sold (thus owned), which could explain the dearth of internet exposure.

One of those pictured looks to have something going on with the woofer surround. Might want to inquire about that before committing to purchase.

But then, these were sold with a "lifetime guarantee," so how could you go wrong?!

 

[Neck Beard]

Love those chunky grills! ...I bet they sound pretty good too(?).

 

[Lavane]

Hello AK, so these popped up for sale about a 1/2 mile from me for what I consider a very fair price so I started researching them (you know the drill) but can't find much info out there, even on here. Here's what I've found; These were top- line in '75 with 12" rubber surround , cast frame woofer, same as the great Optimus 5, 3 mids, dome tweeter and walnut veneer cabs AND these are in excellent shape. BUT what concerns me is the wacky cab design. These are only 9" deep but 28" tall and 19" wide. Also I read they have a 1/2" slot on the top rear behind the 3 mids for "360 midfield sound radiance" -seems odd and another guy speculated the woofer chamber is sealed off from this "port" so they may be low effiency with a funky bass character as some RS speakers were. Any info would be appreciated!

I think your right. The slot is probably to let the back wave from the mids to escape. They may sound good. I'm guessing because of the price people either went for the Mach's, Nova 8B's or the Optimus 5's. Even though the cabinet isn't real deep, it's plenty large enough for that woofer.

 

[Adam S]

I think your right. The slot is probably to let the back wave from the mids to escape. They may sound good. I'm guessing because of the price people either went for the Mach's, Nova 8B's or the Optimus 5's. Even though the cabinet isn't real deep, it's plenty large enough for that woofer.

I think I'm gonna go for them if they look as good in person as on the ad. Supposed to go see/buy them Thurs. Or Friday. I do know they are rare and agree with you that most went for the Optimus 8 due to the cheaper price and great reviews it received. I'll definately recap them after a good listen but I think the WAF Will be low on these but this kid is down to 75 bucks so I gotta get them.

 

[Lavane]

One thing you might consider if you like them is to replace the caps on the crossovers. Many if the RS crossovers Are built on the back of the jack plate. Usually you can remove the screws from the inside and pop them out to recap.
I've recapped several RS speakers. They used some pretty cheap electrolytic caps that dry out over time. New poly film caps tend to wake them right up.

 

[Adam S]

Yes I plan to recap these- I mentioned that in my first response.These actually ran nice Elnas which I've seen test in spec at 40+ years but yea the recap is an easy process on these , pull from inside and reseal the flange after.I'm gonna run them for awhile stock and make sure all drivers are good before I get too attatched. I'll post my impresssions of SQ after the weekend. Stay Well!

One thing you might consider if you like them is to replace the caps on the crossovers. Many if the RS crossovers Are built on the back of the jack plate. Usually you can remove the screws from the inside and pop them out to recap.
I've recapped several RS speakers. They used some pretty cheap electrolytic caps that dry out over time. New poly film caps tend to wake them right up.

 

[Lavane]

I'm curious to hear what you think of them. Many of the Optimus line were pretty good. I still have a pair of the 8" Optimus 2B's. I bought 1B's and 2B's new back in '75 I think. I wish I had kept the 1B's.

 

[Adam S]

Got these today and cleaned up the cabs and removed these big woofers to clean the pots and they nice but I know they will sound better after I recap them and play with placement in the main system. The mid panel is sealed from the lower section and the "vent" is the same opening on the back which makes more sense. The rubber surrounds are mint, the kid used a stock photo for the ad and the grills had never been removed untill today. Very happy for 80 bucks delivered.

 

[f0427ea]

pre "Mach One's" , look at the driver layout , mid's on top , sealed off from woofer and tweeter, offset tweeter in middle , shallow cabinet.

 

[bowtie427ss]

BUT what concerns me is the wacky cab design.

What's wacky about a cabinet that barely strays from what is considered the golden ratio for dimensions?

Golden ratio refers to cabinet dimensions where D x W x H are relative to each other by a ratio of 1:2:3

 

[Tim D]

A lot of the RS speakers had long lasting rubber surrounds. It is a little known plus for many RS speaker models that the surrounds don't rot. I'll be interested to hear what you think about them after a recap. Do you have any other speakers in good condition to compare them against?

 

[Bodyblue]

I am curious to see what you think as well. I just recapped my Optimus 1s and 5s last month am really impressed by them. One thing they amaze me with is their ability to absorb power. They just drink it up and spit it out.

 

[Lavane]

A lot of the RS speakers had long lasting rubber surrounds. It is a little known plus for many RS speaker models that the surrounds don't rot. I'll be interested to hear what you think about them after a recap. Do you have any other speakers in good condition to compare them against?

The foam surrounds on a pair of Optimus 2B's I own don't show any signs of rotting.

 

[Bodyblue]

A lot of the RS speakers had long lasting rubber surrounds. It is a little known plus for many RS speaker models that the surrounds don't rot. I'll be interested to hear what you think about them after a recap. Do you have any other speakers in good condition to compare them against?

My O1s, O5s and Nova 6s all have surrounds that are perfect.

 

[Bodyblue]

 

[Lavane]

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Got these today and cleaned up the cabs and removed these big woofers to clean the pots and they nice but I know they will sound better after I recap them and play with placement in the main system. The mid panel is sealed from the lower section and the "vent" is the same opening on the back which makes more sense. The rubber surrounds are mint, the kid used a stock photo for the ad and the grills had never been removed untill today. Very happy for 80 bucks delivered.

The rear vent letting the back wave of the mids any tweeter out is interesting.
Bouncing off the wall out of phase may add some depth.

 

[Lavane]

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I would like to see the difference in crossovers between the Optimus 5's and 5B's. It may just be the coil for the woofer since that seems to be the only difference between the drivers.

 

[HTHMAN]

Optimus 9 was listed for 1974 and 1975 only. That would suggest relatively few sold (thus owned), which could explain the dearth of internet exposure.

One of those pictured looks to have something going on with the woofer surround. Might want to inquire about that before committing to purchase.

But then, these were sold with a "lifetime guarantee," so how could you go wrong?!

That type of cast woofer had cloth surrounds in the Optimus 1 and 5. Looks like someone may have refoamed them.