The Clone Wars: Henry Kloss And Radio Shack

[Bodyblue]

The used speaker market around me lately had been pretty boring.....just a bunch of 80s rack system crap mostly. But yesterday I was bored and looked for Realistic on CL and there was a listing for a pair of Optimus 5 speakers. I did the usual AK search about them and the consensus was pretty favorable: a clone of the KLH 5 built by Foster for RS. So I messaged the seller that I was interested and had a message back 5 minutes later. The list price was pretty low really ($50) but I had to ask if he would take $40 and he said yes. The cabinets had the usual 45+ years of nicks and scratches but no major problems.

When I got them home today I hooked them up to my front Marantz system and fired them up......and, they sound pretty damned good. The pots on the back had just a bit of fuzz when moving them but all the drivers are working and they have a pretty wide soundstage...a bit wider than the Imperial 6s that are usually there. Since the woofer is so big and the cabinet on the small side I was afraid the bass would not be that great but I was surprised again, its deep and solid. I think the Imperials go a bit deeper and for sure the Imperials are much easier to drive but the RS units were a lot better than I expected. I only listened to them for a few minutes because I wanted to get them outside so I could sand and oil them.

I hit them with 220 grain sand paper and the usual Watco Dark Walnut Danish oil and they look pretty decent. They are drying now and after that they will go into one of the bedroom systems, probably hooked to the Yamaha CR 1040. They need a decent amount of power it seems and I am guessing the sensitivity is around 87 db or so.....maybe a bit more.

Here are the 5s when I first brought them home and after a quick sand and oil.

More impressions and pics to come a bit later.

 

[Bodyblue]

what I was going to say above and forgot was that many of the RS Nova and Optimus speakers were influenced by Kloss designs, especially in the early 70s.

 

[BigElCat]

Those cleaned up nice.

Look great with the Marantz wood component cases.

 

[Drumolator]

They look very good. Enjoy! Peace and goodwill.

 

[Lavane]

Your right. Those cabinets do seem small now that I see them next to your system. I had a pair of speakers once with 15" woofers in a sealed cabinet that I thought were too shallow but they wound up sounding fine. I like the raised front trim on the Optimus line.

 

[Bodyblue]

Your right. Those cabinets do seem small now that I see them next to your system. I had a pair of speakers once with 15" woofers in a sealed cabinet that I thought were too shallow but they wound up sounding fine. I like the raised front trim on the Optimus line.

Here is another shot near the KLH 6 and Imperial 5.

 

[Bodyblue]

Oh and I had to use old RCA plugs to cap inlets.

 

[Bodyblue]

Ok I have them up and running in our bedroom with the Yamaha 1040. The speakers are about 20 feet apart in the corners. Any speaker put there has great bass response and these are no different.

They just eat up the power and really start sparkling at higher volumes. The bass sounds very similar to the KLH 6s actually and I am surprised that they have as much as they do with a cab/woofer size like this. But as I learned from the A25s some speakers go against conventional thinking regarding volume to woofer size.

 

[Bodyblue]

Your right. Those cabinets do seem small now that I see them next to your system. I had a pair of speakers once with 15" woofers in a sealed cabinet that I thought were too shallow but they wound up sounding fine. I like the raised front trim on the Optimus line.

I like the raised front trim as well....and I really like the dark grill cloth as well.

In the 72 catalog (I think) the listing calls the Optimus 5 their "finest" speaker. And I think they are not wrong. It is a damn good effort and the usual RS benefits like walnut veneer make it a great value for the time.

And it is the best 40 bones I have ever spent.

 

[Bodyblue]

I have been sitting on our bed flipping through different types of music and have co.e to some interesting conclusions: first is that the totally spank my recapped Pioneer CS 88s and take their lunch money.

Second is that they are very very close to my KLH 6s, almost too close.

And third, and I am expecting a riot after saying this, I like them better than my Dynaco A25s. You k ow when a thought start creeping in from the back of your mind? That thought is that I am selling the Dynacos after listening to the Realistics this afternoon.

 

[E-Stat]

It's a shame they didn't tightly align the tweeters vertically in a quasi-line array.

 

[rkgren1]

Yep.
I run a set of Optimus 5B's in my living room system.
Excellent speakers, esp. pair with a set of Minimus 7s on the other channel.
The Mini 7's add a noticeable bit of sparkle to the mid-hi range.
Mine are not as cosmetically nice as Blue's, but they sound great.

Be very careful to not impact that trim round the grills.
The glue holding it all together comes apart too easily.

I think that, of the 3 small drivers, the bottom 2 are mids and the top one is a tweeter.
Can anyone confirm?

 

[Gazdatronik]

I think that, of the 3 small drivers, the bottom 2 are mids and the top one is a tweeter.
Can anyone confirm?

yes

 

[f0427ea]

Yep.
I run a set of Optimus 5B's in my living room system.
Excellent speakers, esp. pair with a set of Minimus 7s on the other channel.
The Mini 7's add a noticeable bit of sparkle to the mid-hi range.
Mine are not as cosmetically nice as Blue's, but they sound great.

Be very careful to not impact that trim round the grills.
The glue holding it all together comes apart too easily.

I think that, of the 3 small drivers, the bottom 2 are mids and the top one is a tweeter.
Can anyone confirm?

you got it , the top is a tweeter the 2 middle are midrange

 

[E-Stat]

you got it , the top is a tweeter the 2 middle are midrange

I guess when all you've got is a single driver with which to work, you try to make the best of it.

 

[Bodyblue]

I was fully planning on having to recap them but now I am not nearly as sure. Now the Yamaha is an ice cold clinical sounding unit and I have the pots in the back set a bit past normal for the mids and about halfway past normal for the highs. Our bedroom is a super soft room so I will have to try them with a different receiver. I am going to wait a few days as I have a Kenwood 8010 and a MCS 3260 inbound so I will wait til I get at least one of them to change. But even with a very warm unit I dont think they will need to be capped. The sounded fine on my Marantz 250/1060.

 

[FluxT]

Those look very similar to the Nova 8’s that are used in the lobby/common area of my school apartment building. They sound fairly nice, but I feel like the twin mids lead to some funky dispersion issues, but they’re better when laid on their side with tweeters out. However, they are due for a recap and a new tweeter soon. They’re predominantly for playing TV dialog and soft indie music into a large formal space, and for that they do a commendable job.

 

[Bodyblue]

Those look very similar to the Nova 8’s that are used in the lobby/common area of my school apartment building. They sound fairly nice, but I feel like the twin mids lead to some funky dispersion issues, but they’re better when laid on their side with tweeters out. However, they are due for a recap and a new tweeter soon. They’re predominantly for playing TV dialog and soft indie music into a large formal space, and for that they do a commendable job.

The Nova 8s are the Nova version of the 5Bs. Later on in the 70s the Nova line was introduced to be a fancier looking line of speakers. They had the lattice grills and later on they had better drivers and different controls. But in the early 70s the Optimus line was the better stuff.

I don't notice any dispersion issues. I had them in two different rooms and all i noticed that while the soundstage is wide it does have a definite cut off. In the bedroom where they are now they are in the corners and toed in and I don't notice it.

 

[woofercooker]

I bought a pair of these Optimus 5 speakers a while back and liked them right away.. I did get them recapped with regular electrolytic type and they did sound brighter. a few years later I bought a pair of VL Nova 8b from a fellow AK member and now I rarely listen to the Optimus 5. I will still keep them to show what the differences in sound are between the two. I did apply AR sealant on the Optimus 5 woofer after a application some acetone because they were lacking bass. Not so much now. Hopefully yours won't need that. Here is a older photo when I used them more.

 

[Bodyblue]

I bought a pair of these Optimus 5 speakers a while back and liked them right away.. I did get them recapped with regular electrolytic type and they did sound brighter. a few years later I bought a pair of VL Nova 8b from a fellow AK member and now I rarely listen to the Optimus 5. I will still keep them to show what the differences in sound are between the two. I did apply AR sealant on the Optimus 5 woofer after a application some acetone because they were lacking bass. Not so much now. Hopefully yours won't need that. Here is a older photo when I used them more.View attachment 1453738

Were your surrounds stiff? Mine are the rubber and are still in perfect condition. My Nova 7s had the resin infused paper like the KLH's but these don't which actually surprised me. The Nova 7Bs went from the paper to rubber around 76 or so.