Infinity RS-1 crossover - Rocket science?

[OldiesButGoodies]

MacG - that is a new Infinity crossover.  that is what Infinity shipped withe the RS-1s originally,  I am using the Rane as an alternative.   

The Infinity box is supposed to do some rocket science magic  to extend the tower's bass to 20hz (claimed to be a "servo" circuit,  but not really true as there is no accelerometer in the woofers to inform the x-over as to where the cones are).  Unfortunately I have not been able to get one that works as advertised yet.  I am troubleshooting this one, but I may need to have it replaced as well (second one). That is too bad because this one looks mint. Once I do I get one that works I will need to redo the room with an RTA.  I hope to have one by then and not bother you again. 

Pepe,

What's the new box on the Rane?  It wasn't there the other day.

I like the idea of building them using Lak tables from Ikea.  I think they are $8 each.  Simple and sturdy, looks good IMO, and you can tailor the inter-shelf size to your specific needs.

(this example has a Polk center channel wedged-in that looks less than elegant [hey - it was a prototype],  but you get the point)



The Mexican

[SunnyDaze]

The Infinity box is supposed to do some rocket science magic 

Did you tell me that the guy who built them is a real aerospace engineer?

[OldiesButGoodies]

Read up on him here:

http://www.stereophile.com/content/arnie-nudell-here-infinity

Arnie Nudell,  nuclear physicist. Applied inertial navigation technology used to help target bombs in Vietnam to bass cabinet design.   Typical underachiever shit. 

[Anders]

I heard the Infinity IRS speakers twice.
Once with Conrad Johnson electronics and once with Mark Levinson which included a custom reel to reel playing a copy of a mastertape of some Pink Floyd music.
Best i've heard except for the fact that the image tended to wander up and down a bit.
But they really didn't sound any better than my Acoustats except that they could play a bit louder.
But the image wander bothered me a bit because my Acoustats have a very stable image.

[OldiesButGoodies]

I understand that the reason that Arnie Nudell designed the IRS series the way he did as a point source speaker is that the manufacturing technology for EMIMs back then did not produce sufficiently consistent drivers - there is always variability in output.  Hence the 3rd EMIM down being dominant an the others operating at various frequency ranges.  So it would not be surprising to find the image project wandering a bit. 

Mine are pretty stable image-wise.  The addition of fiber fill (cotton) in the EMIM cavities makes a huge improvement.  My left speaker EMIMs have it while I work my way through the right,  and that helps the imaging too.

Pepe

[MacGeek]

Might explain why you sensed some channel imbalance.  With the addition of the fiber fill to the other channel and proper set up of the the "box" who knows how good the system may sound.

By the way, no bother doing the room analysis.  I learn something every time I do one and always get to hear something new.  Next time needs to be with a substitute for the coffee.

[OldiesButGoodies]

Great - that can be arranged.  I got the original Infinity cross-over working,  found a bad resistor hidden under heat shrink and 50 cents and two hours later it sprang to life.  It changes the tone of the speakers so the original curve does not apply.

Testing Reverend's Carverfest tube amp on the mid-high towers. Surprisingly sweet sound from that tiny amp. At low volumes the Infinitys sing with it.

[MacGeek]

So you don't need the Rane?  Or do they do different things?