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I need help in deciding best center for Polk audio rti12 and csi5 center. I was looking at the volts for surround duty and wasn't sure which one would be better for a room that is 24x32 ft. I have plenty of Amplification. but not using amps won't be a worry.
 

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I'm interested in what people have to say about this as well. I'm currently using the fxia4 surrounds and want to replace them with volt 's. Has anyone had the chance to hear both?
 

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Your asking a pretty specific question.
I can't answer you but I can tell you I used the rti2s as surrounds and I strongly prefer the JBL8340s you see on cinema walls, that I found cheap.

The volts are also higher sensitivity then the polks , which are 88db. There's no doubt the volts would outgun them, but you'll have to be the one to decide if you want louder surrounds that potentially can sound better.

I was going to go the same route with the RTI tower speakers as well, but decided to sell the surrounds DIY instead. They are great commercial speakers, but nothing DIY can't best.

Went off topic a little but hopefully it helps..
 

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To pick a nit: sensitivity is v/dB. efficiency is W/dB, so other things being equal the 4 ohm version of a driver will be 3 dB more sensitive but same efficiency as the 8 ohm version
Fair enough, but when Crown and JBL Pro call sensitivity "w/dB" I'm in good company. :)

EDIT: I guess it's really sensitivity, normalized to 1 watt, that is most meaningful to me, as the watts (and amps) are what are in short supply?
For instance, max watts before some distortion is the figure of merit comparing amplifiers: X watts vs Y watts.
It's also the figure of merit for the power handling of a loudspeaker driver.
If my watts are limited, then I want to know: "How many will be used by the speaker?" and "How many will the speaker take before we get objectionable distortion?"

It's true though, hearing "dB/w" suggests the question, "At what frequency?"
 

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I have the Yamaha 3050 flagship amp and I can tell you that receivers simply can't produce undistorted sound even at 30w

My speakers are super efficient 94db (qsc sc1120) and with the Yamaha 3050 it did sound good for ht and ok for music but when I started using qsc dca cinema amps its a completely different level of HF accuracy and dynamics . Receivers simply can't compete with a dedicated amp even at moderate volume I could hear a difference in low mid and highs. The sound resolution of a dedicated external amp is different. My old Sony amp stdn 1030 sounded better than the Yamaha but didn't allow me to pair the external amp. Use qsc DCA or plx amps for HT or loud live music or buy active speakers with class d amps embedded ....

Surround is mostly muffled ambient sound but at times the dynamic range and voices in some quality mixes will justify external amp. If you are looking to do the best possible I will vote for external amp for surrounds also.

Open up a 2 channel cinema/live sound amp to understand how complex it is to reproduce accurate sound. Its not just power supply for high output ....

If I built my HT again I would use active speakers everywhere ... Probably qsc kw 122 or else for front LCR and surrounfs to timber match it. The surrounds choice really depend on the room size and setup.
Dispression pattern desired, seat coverage, level of SPL(102 pick) at each seat , off axis response of the speakers chosen etc...
Coaxial speakers allow wide coverage but unless you use a very large woofer its never going to be as accurate for music as separate 2way horn speaker if you don't mate it to a second woofer with 200-300hz crossover to minimise the cone movement.
The reason for that is that at high SPL the cone movement effects the HF waves as the waiveguide is the cone itself (ripple effect).
Not sure how audiable it is for critical listeners but
Jbl synthesis and porcella for example prefered to use horns for surrounds. qsc critical listening for small room setup also uses horn (sr8200). I didn't see many small atmos studios that choose coxials for surrounds in small rooms with lower ceilings. Coxials give you a better off axis response for seats that are off axis. in untreated rooms the off axis is better because of their constant directivity.but if your seats are anyway on axis and you listen to direct radiators (monopoles) they may sound more accurate and less colored by the room acoustics. If you room is well treated uncontroled high dispression may be a bad idea ...
 

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I have the Yamaha 3050 flagship best and I can tell you that receivers simply can't produce undistorted sound even at 30w
Most people here will disagree with you. Did you measure that your receiver was only putting out 30w of its 100w+ capability?

You're suggesting that very experienced people are wrong when they find their receivers, when playing within their capabilities, produce the same sound as using an external amp.
And that the reviewers of receivers showing, under testing, the distortion under load, are wrong...that the distortion is actually quite high at--what-- 1w? 10w?

Maybe your flagship receiver has broken amp section?
 

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My flagship receiver is new. Yamaha support admitted that it simply can't compete with a dedicated external amp.
The qsc sc1120 doesn't need more than 30w to become very loud 93.9db at 30w with 2 speakers corner loaded gives me 108 SPL 9ft away. Very loud at 30w with these speakers ...
I never said that they Yamaha receiver isn't load at 30w. It is lud enough. But the sound fidelity/ accuracy and dynamics is not as good if you are a critical listener. The Yamaha is a good receiver very detailed and dynamic but it can't compete with a dedicated amp in sound reproduction for the LCR channels. Its very usefull as a pre amp but I not as good as the Yamaha dedicated pre amp which I don't own... But wish I did. My next purchase will be a pre amp only. Receivers have higher distortion. The numbers on the spec are nice 0.x THD % at x watts but I can really here the diffrence even at low output
 
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