Optimus-40

 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2630
Registered: Dec-03
For anyone interested, I picked up a pair of unique speakers today.
Yah I know realistic speakers must be garb right, well that's what I figured
but there design and the price made me grab em ($3 for the pair used of'course)

Well they are a larger then normal 2-way (8" woof 3" tweet) with a 10"
passive radiator and they are also an attempt at being time aligned as the
top portion of the cabinet where the tweeter is mounted is set back about 2".

After taking them apart to inspect, a very intersting xover reveals it'self, the
woofer is run full range (no xover) and all the tweet has is 1 cap! Now if that
isn't a pretty minumal xover then I don't know what is. After checking them
out on the garage setup I see why they have no xover on the woofer as there
is no highs comming from that unit and the mids that are there sound great.
My guess is the 8" driver rolls off naturaly to a point then the tweet takes over.

From the limited testing so far this speaker system has some potential and I
am curious to try these on the 300B with some jazz and acoustical music
(as I do not see them being a loud/big rock speaker).

The extremely limited info I have found for these speakers so far (Optimus-40)
Power Input: 75 Watts Max
Frequency Response: 40 Hz to 20,000 Hz
Sensitivity: 89 dB @ 1 W/m

Wish I could get a phase and impedance chart for them to really try and determine if
weather they fit the mold of a "tube friendly speaker" but the simple xover and decent
sensitivity have me intrigued though, keep yu posted.

If anyone has some info I'm all ears!
 

Silver Member
Username: Cheapskate

Post Number: 242
Registered: Mar-04
why would you want to put expensive amplification behind cheap speakers?

at 89dB... no... i don't think tubes would be the best bet. tubes like efficient speakers best. (92dB and up)

if you like the sound of them already, then why not at least get used to them before making changes. do they sound a little bright? that would be a good reason to want tubes.

time aligned huh? i wouldn't expect that from radio shack LOL.

oh! wait!

do your tweeters look sort of like figure 8s when you look down on them? i'm starting to think you might have LINNAEUM tweetered speakers. i tried, but couldn't find a pic to verify this.

if so, your speakers actually got a favorable review in either stereophile or the now defunct audio (i think THAT'S where i read the review) about 5 years ago give or take.

if that's the model you have... there's a full review of that speaker in one of those two mags.

the linaeum tweeter is a variation on the piezoelectric drivers often seen in cheaper horn tweeters, but for a minute... linaeums were hot items and there even was a linaeum brand seperate from radio shack.

do your speakers look something like this?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem%26item%3D5800079140

if so, use the word linaeum as a keyword to find more info.

the internet SUCKS! all the world's info my hiney! LOL items that went out of production less than 10 years ago are often impossible to find info on.

sometimes... nothing beats a good old fashioned library.
 

Silver Member
Username: Thx_3417

Post Number: 864
Registered: May-05
Damn I, remember seeing the "Opimus 2E" at "Tandy" around 16 years ago there about, interesting design, a few of these placed around the room for the surround array, I'm sure they will give a unique sound...

Upload
 

Silver Member
Username: Cheapskate

Post Number: 247
Registered: Mar-04
yes.. there they are. those tweeters were supposed to be "the next big thing" for a minute. i guess because they're dipoles which made their image more spacious.

there was a woodgrained model (8" woofer if memory serves me right) that had a front port.

piezo tweeters usually only have caps as crossovers, even with 15" woofer DJ speakers. the woofers operate full range.
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2631
Registered: Dec-03
Budget minded I don't understand all this.

"why would you want to put expensive amplification behind cheap speakers?

at 89dB... no... i don't think tubes would be the best bet. tubes like efficient speakers best. (92dB and up)

if you like the sound of them already, then why not at least get used to them before making changes. do they sound a little bright? that would be a good reason to want tubes. "

For one I would use my amp because I have it, why not see how it sounds.

And yes at 89db it is starting to fall off some but even at 4 watts with my
amp I should have around 95db of sound which should be plenty to listen too.
While yes efficency is a concern for low power tube amps there are others
that are just as important if not more like uncomplicated xovers and phase
along with impeadence but I also have some higher powered tube amps and solid state.
I prefer the sound of tubes generally but also like a good solid state amp.

I'm not sure what you mean by use them before making changes. I'm not making
any changes I'm using them on a multitude of gear I have to see where they work
there best. This is what I do with gear to evaluate how it works.

And just because the name has radioshack behind it does not necasarily mean
they are a cheap speaker, sure that was my thoughts when I read the name
but I tore them apart to investigate and listened to them to determine. Any
company "can" make a good product if they want to, there is no major secret
behind making a good speaker if the manufacturer has that in mind for there design concept.

No these do not look like those and I will post some pics later. They are
about 2.5 feet tall and about 15" wide with the top recessed back about 2"
where the tweeter sets they have a 10" passive radiator at the bottem then an 8"
woofer above that then a tweeter above that.

Budget my post was not knocking you, just anwering all your questions.

As I build and rebuild speakers not to mention am a service tech also that I allways
take things apart to see how there put together and determine there quality but
put them back together in there original state to see how they perform.

So far these speakers are impressing me. They are wood veneered and take oil.
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5204
Registered: May-04


" ... I always
take things apart to see how they're put together ... "

Kegger, how many Barbie dolls did your sisters go through like this?


3" tweeters, huh? Paper cone? Any name on the tweeters?




 

Silver Member
Username: Thx_3417

Post Number: 879
Registered: May-05
Upload

Paper cone, what on the HF?

Is that like a bog roll?

Man that's crawl.....
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2633
Registered: Dec-03
Jan I can't remember that far back but I probably did tear apart her barbie dolls.

Yes the tweeter is aprox. 3" round with a cage over it so I can't see what is under
it. There is also a foam ring around the tweeter that is light grey and very dense.
The only driver I pulled so far was the passive radiator as I was guessing that's
what it was. I will pul the other drivers and see if they say anything on them. My guess
would be theses are older radio shack drivers as I don't believe they used others
parts but I could be completely wrong about that.
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2634
Registered: Dec-03
Here's a pic and I've been listening to these for about a couple hours now.
Impressions so far is that they do voices wonderful both male and female.
Seem to have a little trouble with more complicated/busy passages of music.
Bass is very good, may be a tad rolled off at the top. They seem to like about
10-15 watts of power to really let um shine so yes they do stress the 300B a
little to much. But they do like the 40 watt single ended golden tube audio amp.

Need to play with them some more but what I've heard so far sounds much better
then some other speakers I've picked up recently not to mention others in the past.

Rolled off at the top may be giving the wrong impression as they don't really roll off
but more of they don't extend the frequency range as high as other speakers which
may make them a candidate for a supertweeter to extend there range a bit.

Upload
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5208
Registered: May-04


Probably if you pried the screen from in front of the tweeter it would give you more sense of high frequency content. And, get that pot out of the line.

The Golden Audio is single ended? At 40 watts per channel?




 

Silver Member
Username: Thx_3417

Post Number: 918
Registered: May-05
KEGGER

have you got an RTA and a test disc with some spot frequencies, this way you will be able to tell what it can and can not do within the tolerances of it workable capability...

Oh and a SPL db meter as well....
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2635
Registered: Dec-03
Some say the golden tube audio se-40 amps are around 36-37 watts a channel.

Yes it is a single ended unit running 6 5881 tubes (3 per side) it can also
be ran as a mono block producing 80w (well probably really about 73w).
The tubes in this amp are run very very hot and not all output tubes in there
substitution range will handle how this amp runs.

These amps are very hard on tubes, it takes a rugged tube with a high voltage
rating and they don't last a long time. I have replaced all the pasive parts inside
both my amps with higher tolerence parts because of the needs of these amps.
(sonicraft had kits for these amps as they need to be rebuilt like mine are)

I also agree the pot has to go but I wanted to listen to them the way they
were designed. I may make some alterations later, like do away with the
pot/replace the cap in the xover/see about mating a supertweeter on top.


Andy yes I have ways to test the speaker to determine what it can and can't do.
At this point I'm just listening to them and have many things I need to finish before
I get serious with testing and or moding something like this.

At this point there just another pair of speakers to add the list of many others.
But when I get something new I do like to check it out to some degree. Also
wanted to throw up the thread for others to see these and wonder if anyone
had any knowlage of them or comments. Thanks!
 

Silver Member
Username: Cheapskate

Post Number: 251
Registered: Mar-04
i'm just leery of radio shack as i've bought ALOT of stuff from them that is junk... cassettes that stick and jam like crazy, an 8" "woofer" that makes abolutely no bass, an electret condenser microphone that can't keep it's grille on and that has a faulty power switch and a 1/4" splicing block that doesn't even hold the tape firmly, but that let's it wiggle around defeating the purpose of using it to begin with and so on. i've had way too many bad experiences with radio shack to give them the benefit of the doubt.

is there a saying about "fool me four times?"

another issue i have with radio shack is that they overprice their rebranded equipment eg. pioneer recievers cost $100 more with the optimus logo and the casio sk-1 sampling keyboard that i bought for $50 at k mart was selling for $99 as an optimus.

yes.. i definately have an anti radioshack bias. but you also see, that i did mention that the linaeum model they sold did get a favorable review too. when they DO source gear that doesn't suck, they deserve credit. i'm up front about my biases, but will set them aside when there's a truth that goes against them.

if you like trial and error, and can affor it... more power to you. i like to zero in on a specific goal and gear that meets it before hand myself. my attempt at trial and error landed me a pair of mission m71s that ended up as my PC speakers.

if you're that much into DIY, why not look for a tube amp kit? they are available for alot less than even the cheapest production units if you shop around. you could build it with upgraded alps pots etc. to begin with.
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2636
Registered: Dec-03
Budget you more than likely don't know me or what I have or what I do so I'll give
you the benefit of the dought as to your response to my checking out these speakers.

I am a tech by both trade and hobby, I have at least "no kidding" 40 amps or so of
both solid state and tube along with many preamps and sources not to mention at
least that many other speakers. I have a good ear and a pretty good eye for things
that have potential. I've recently been laid off so I've been going to garage sales
and thrift stores to find things I can repair and rebuild then resell them but I also
find things for myself all the time too and the price I pay is very very low. I paid $3
for this pair of speakers that looked intriguing to me, so to check them out I put
them through some of the gear I have to evaluate them. I would think many people
would envy the gear I have and the ability to evaluate something in a way that others
can not. When most buy something they have to hope it will work with there setup
even after all the research someone has done it's still trial and error that it works
as well as someone may think it will. Trying something in the store for a few hours
is very different then the home envirionment let alone to try it with many other pieces
to see where they work there best or even the quality of the gear.

So yes I have no problem picking something up that may be suspect if I get it cheap
and it looks to have potential so I can bring it home to evaluate it further for both it's
build quality and sonics comparred to many other pieces. (real world eval)

With the amount of gear I've worked on and used, the amount of info and knowlage I've
gained is unmeasurable and I for one feel very fortunate for this. Yes audio is a hobby
for me that I love so the more gear I get to use the better!
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5229
Registered: May-04


Gear hog! smiley
 

Silver Member
Username: Thx_3417

Post Number: 982
Registered: May-05
KEGGER

It's an interesting design is that a 12inc Bass LF driver with an 8inc Bass Mid and 2inc HF.

It's hard to tell by the picture, but I'm sure I'm close?
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2650
Registered: Dec-03
Andy If you go to the first post it gives all the speaker sizes.

A very interesting speaker with great midrange and bass.
 

Silver Member
Username: Cheapskate

Post Number: 264
Registered: Mar-04
yes... i very easily saw in your LATER replies that you are a knowledgeable audiophile. i jumped to the conclusion that you were a newb because you thought that "radio crap" (i'll never shake my bias LOL) speakers were the best thing ever made.

i'd personally rather buy something just once if possible myself. i love my superzeros, but i've found my nirvana after hearing planars. i can see myself as being happy with them once i revamp.

i've only recently dropped 20 years worth of steadfast "acoustic suspension minimonitors with soft domes on solid state" bias, so i'm coming from an "i know exactly what i like" frame of mind until i encountered something i'd never heard before. i DID hear flat panels once before, but they sounded like aluminum foil so i dismissed them ever since.

if you like to tinker... then by all means, get a decent tube amp JUST so you'll always have one for whatever future gear you get. the ONE time i heard a tube amp on phase tech speakers, i wasn't impressed. it might have been the speaker's fault.

whatever gear pleases your ears is perfect for you. if you have as much gear as you say, then you surely do have alot of real world practical in home experience that most of us don't.

i gave my "newbie" preconceptions up as soon as you started talking audioese LOL. from the DEEP tech terms you dropped, it looks like you're deeper in the hobby than i am. i would never recommend DIY to a total newb.

still... i already know exactly where i want to move next, and forsee staying there once i get there barring broken gear and minor tweaks.
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5283
Registered: May-04


Kegger is so deep into this hobby, he is up to his eyeballs in gear. Hey, Kegger, didn't somebody else recommend you get a tube amp?
 

Silver Member
Username: Joe_c

Atlanta, GA

Post Number: 998
Registered: Mar-05
Keg, I thought I read that sensitivity was one of the great misunderstandings of tube + speaker setups.

http://www.symphonysound.com/articles/tubefriendly.html
 

Gold Member
Username: Kegger

Warren, MICHIGAN

Post Number: 2654
Registered: Dec-03
Budget thanks!

Yes Jan when I was a wee punk and sniffely interested in tubes some wise gentlemen
did nudge me in that direction, humm who was that!

Joseph yes sensativity is not the only criteria by a long shot. But it can help
a lot with an amp that is not very powerful. SMILEY!
 

Gold Member
Username: Joe_c

Atlanta, GA

Post Number: 1007
Registered: Mar-05
Jan, your head cannot get any bigger!
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5291
Registered: May-04


Of course not! I am a grown up.
 

MTGG
Unregistered guest
All evidence to the contrary!
 

Gold Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 5306
Registered: May-04


Says who?! I got papers to prove it!
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