Speaker ID

[Jenkster]

My son found these speakers in a storage unit. I believe they are Infinity’s but not sure. Any help would be greatly appreciated,
Thanks!

 

[swechsler]

Infinity Quantum 3. Well worth fixing up. Plenty of info on here and elsewhere on the Quantum series.

 

[Buck Rogers]

Nice~~!

 

[Jenkster]

Infinity Quantum 3. Well worth fixing up. Plenty of info on here and elsewhere on the Quantum series.

Many thanks! Looks like a definite project. The cabinets are in pretty good shape, not due about the drivers. Obviously the woofers need work.

 

[Nyjblbob]

Is that the way they were made with the overlapping tweeters?
Bobhorn
Nice cabinets

 

[swechsler]

Is that the way they were made with the overlapping tweeters?

Yes, it's a mini line source, presumably the tilt is to partially compensate for the EMIT's poor vertical dispersion. The TOTL model (QLS-1) was an actual line source.

 

[Buck Rogers]

No, They are not supposed to be overlapped.

Someone was messing with them or replaced them.

It's common to blown them out.

You can replace the Diaphragm's but you need a He-Man Gorilla grip to pull it off!

 

[swechsler]

No, They never overlapped.

To be clear, they don't actually overlap, but the top tweeter is supposed to be angled up.

 

[rmeade]

There are quite a number of AK threads that describe a need for a robust amplifier to drive the Quantum 3 speakers. The general consensus is that you need a high-current, high-power solid-state amplifier that is highly stable down to 4 ohms and lower.
Like many vintage Infinity speakers from the late 1970s, the Quantum 3 features a complex crossover network and a specialized 12-inch Watkins Dual-Drive woofer. This combination causes the speaker's impedance to drop to dangerously low levels at specific bass frequencies. If paired with an underpowered or unstable amplifier, they can trigger the amp's protection circuit or cause it to overheat and fail—earning the Quantum 3 speakers the nickname "amp killers".

Thread 'Infinity Quantum 3'

Jan 22, 2010

What follows are my initial impressions of what Infinity considered, at one time, the "... third-best speaker in the world."

I don't think it's necessary to get into the lineage and intricacies of the Quantum series or the evolution of the Quantum 3, as this information is documented elsewhere by people much more knowledgeable than I. I will say that the Quantum 3 is a vastly scaled-down version of their erstwhile TOTL Quantum Line Source (QLS-1), and, while it uses all the same drivers, it uses less of them (save for the woofer and mid-bass coupler). The hallmarks of the Quantum...

• M Jarve
• Replies: 51
• Forum: Speakers