# Tune for new dual PC13 Ultras...?



## Vader (Jul 8, 2006)

Hi all!

Well, I just received my new dual PC13 Ultra Cylinders (replacing dual 20-39 PC+ cylinders), and I now need to decide what tune is safe for me to run in (the main cause for the upgrade in the first place). With the PC+ Cylinders (20Hz tune), I was extremely careful (paranoid?) about about bottoming the drivers (every time a relatively hot transient hit, I would wonder if any damage was sustained). My HT is about 3350 ft^3, and I listen at about 10-15db below reference (meaning the MV ranges from -80 --> +18, and my usual setting is about -13). I found that the smoothest FR was yielded by flanking the front channel, so they are not quite co-located (about 8ft apart, symmetrically placed 11 ft from the "sweet spot").

<deep breath>

My question is, can I safely run in the 15Hz tune on the Ultras (better excursion limits?), and still have sufficient headroom to avoid bottoming, or should I stick with the 20Hz tune? Thanks!


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## drdoan (Aug 30, 2006)

I think you should pose that question to SVS. Dennis


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## Vader (Jul 8, 2006)

Dennis,

I am hoping that someone also with Dual PC13 Ultras with a similar (or larger) room size will chime in. If not, I will certainly email Ed...


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## Thomasdk1405 (Jun 23, 2008)

Hi ! I had the previous version of the pc13-ultra for some years back - all speakers referenced to 75db and I can tell you in both 20 hz or 15 hz tune I always tested my bass at 0.0 on the receiver. Pictures and everything rattled (was I affraid that picture of my children would fall down upsetting the wife - it didnt ) - but I can assure you - no worries mate - it's svs - and you got 2 of those monster ??? Remember your helmet. 
In my setup I found that 20 hz was the best - most punch, best sounding - was the tune that frightened me the most - always thougt I lost something when going to 15 hz tune.

I have never reached the limits of my pc13-ultra og pb13-ultra (my current) - I always gave up before it did - so - just fire away !!


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## Vader (Jul 8, 2006)

Thanks, Thomas!

What size room did you have it in?


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## Thomasdk1405 (Jun 23, 2008)

Hi again. Tv room is 35 sq. meters - don't know what this is in feet - and made of concrete. So its not a huge room.


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## Vader (Jul 8, 2006)

Perfect. That works out to around 3000 ft^3 (assuming an 8 ft ceiling). Thanks, Thomas!


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## Sevenfeet (Feb 2, 2009)

It reminds me of my old days of sub buying. My wife was more concerned about waking the kids if we were watching a late night movie. It's not so much a complaint now but if I ever replaced my old AV123 UFW-12 (and I do want to), I might get the noise complaint again from my wife with anything else I'd pick to replace it, especially with any round SVS sub.


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