Upgrade-itis - Prioritization help needed!

[CornerOffice]

I posted this in one of the AVS forums without much luck so I figured I would try here because I have read a lot of knowledgeable and helpful responses. During the winter I seem to come down with a bout of the upgrade virus. From reading the forums, I see I am not alone.

Got a finished basement, 40x32x8 ~ 10,000 cu ft. 90% movies. I like to watch movies fairly loud. I dont fully comprehend yet "reference" but I gather just shy of that threshold. Current setup:

. 60" LG LCD (2011 Model)

. Denon 2311CI

. LG Blu-Ray

. Xbox 360 (2010)

. Klipsch RF82ii Fronts, RC62ii Center

. Orb Audio MOD2 Surrounds

. SVS PC12-NSD

Upgrade ideas:

. Replace Orb Surrounds

. Upgrade SVS to PC13 Ultra

. Upgrade Denon to 3312CI in order to gain pre-outs

. Then buy Emotiva XPA-3 to power front/center

. Upgrade Fronts to RF7ii

. Upgrade Center to RC64ii

. What else?

Ultimately, would be great to do all of them and maybe I will over time. The question is where to start? I can probably swing $2,000 now and pace the other upgrades out over time.

So, lay it on me - how would you prioritize to get the biggest bang first? Appreciate your input - will help me through some paralysis by analysis.

[SuBXeRo]

www.outlawaudio.com get the model 7125 amp, bi amp the left/right and use the rest of the channels to power the rest and get an emotiva UMC-1. thats about ~1500 and a great investment. The power and control of your system is the heart, invest in that and it will really help to make things shine.

Upgrading to rf-7's can be seen as an upgrade. Knowing what i know now about the rf-7's, if i had to buy things brand new and had i not gotten the great deals i ahve, i would have stuck with my rf-5's or rf-3's. I would however keep my rc-7 center and rs-7surrounds.

As far as mating the rc-64 II to the rf-82 II's, i dont know how well it would work but if they do work, that would be a step up for sure! I owuld definitly get surrounds that match the set whether they are bookshelfs or dedicated surrounds.

Sounds to me though that you see changes that you want and you will continue to make them over time.

[Quiet_Hollow]

I like to watch movies fairly loud. I dont fully comprehend yet "reference" but I gather just shy of that threshold.

By THX definition: Reference level is 85 dB SPL + 20 dB of headroom at the listening position from 80 Hz on up to 20 kHz.

So that's 85 dB SPL sustained (dialog, music, and ambient sounds) with peaks up to 105 dB SPL, while sitting on your favorite chair.

In addition, DTS and DD LFE below 80 Hz can go up even higher peaks of 115 dB SPL.

How loud is 85 db SPL in the vocal region? How about 105? What's 115 dB SPL @ 28 Hz feel like?

LOUD. Like it will definitely make you cringe, and you'll be keeping the remote close at hand in case something breaks.

"But you don't have to take my word for it."

Spend the $45 for an SPL meter and check it out.

Now about those reference numbers....what do they mean to you?

It means you take an SPL meter. Turn your reciever on then get it to emit its built-in test tone.

Hold the meter over your seat and turn up your receiver until the meter in-hand reads 75 dB SPL.

Once you've done that, look at the number on the receiver. It could read anything. It could read zero, but will most likely read some negative number (like -20). Add 10 to that number and write it down. That's your reference number. Some AVR's let you tare or reset the number to "zero" at whatever volume you set, but if you know that number you just calculated, that's what's important.

From that number will be where you reference you volume in dB. For example, if "-10 dB" was your reciever's volume setting at reference level, but you're listening to something quietly at "-30 dB", then you can say, "I'm listening at 20 dB below reference."

The use of expressing settings in terms of dB is valueable because, as we'll see in a bit, it allows you to quickly gauge how hard you're asking you're system to work once it's set up correctly.

Are your front three speakers up to the task of reference playback?

Let's take a look...conservatively speaking.

For reference level, you need to put 85 dB SPL across your sofa.

First thing to ask...How loud are they at one watt combined?

Add them up logarithmically using a decibel calculator: 98 dB + 98 dB + 98 dB = 102.7

So, if you put all your speakers outdoors right next to one another, sent a tone through them at say 1000Hz at 2.83 volts (~1 watt @ 8 ohms), then put an SPL meter one meter in front of them, you be reading ~103 dB SPL. Now indoors this SPL will be different. Could be more, could be less. It depends on your room, but for the sake of brevity this number will be a safe bet.

Back to the math...So 1 meter out from your front speakers there's the potential for there to exist 103 dB SPL at some frequency at which your RF's will be loafing along expending ~1 watt each.

So what's happening at your seat?

To figure this out we need to know how far away are your speakers? We'll use the middle of big room and say 4.5 meters (~15 feet).

But we already know that 1 meter out @ ~1 watt the system could be doing 103 dB SPL.

4.5 - 1 = 3.5 meters From your ears to the spot that's rockin' at 103 dB SPL

According to physics, using an SPL distance calculator, every doubling of distance yields a loss of 6 dB SPL. We've got 103 dB @1 meter from the speakers, then 97 dB @ 2 meters, and then 91 dB @ 4 meters.

The next doubling would be a distance of 8 meters [4 meters, doubled] but we only need to go 0.5 meter to finally get to your ears. 0.5 meter is good for approximately under 1 more dB of loss.

The airspace between you and your speakers is significant factor in determining the power your speakers will be using.

So to recap! With all three RF's loafing along on 2.83V, you should be able to read 90 dB SPL at your seat.

But that's already higher than 85 dB SPL for THX reference level, right?

BINGO

At THX reference level, the front three speakers can loaf along at less than one watt of power each... 0.2 watt is more like it.

What about the peaks? What happens for 105 dB SPL? Can they do it?

We'll see. Run the numbers.

This is where the Decibel comes in and why you've been seeing me label these numbers in a specific way. There's dB SPL which is referenced to some miniscule air pressure that only a new-born golden-ear could sense. And then there's dB W which is referenced to power in watts.

We need an extra 20 dB SPL for the peaks. That happens to also require 20 dB W more power. 20 dB W is a power factor of 100

So take 0.1 watt X 100 = 20 watts. Yes, 20 watts per speaker to split your ears at 105 dB SPL 80Hz-20kHz.

Now that you've got the right tools, check it yourself with a SPL meter and a multimeter and the reciever's test tone. You should see 10-12 V AC at the speaker terminals with the SPL meter warbling along at 105 dB SPL and the pets clearing the room.This is the only way to be certain.

Can it go louder? Certainly...

But, this where setting up your HT electronics correctly can make or break things.

"...see ya next time."

* editted to use the larger distance in the OP's room, and included some useful links.

[Chris A]

40x32x8 ~ 10,000 cu ft. 90% movies.

That's a fairly large HT. The biggest problem that I see is below ~60 Hz.

Upgrade SVS to PC13 Ultra.

If you're handy with woodworking tools, I'd most definitely recommend looking at horn-loaded subs, such as Bill Fitzmaurice's Tuba HT or a Danley TH-SPUD DIY design (see page 3 of this thread for a layout drawing). Also see this thread. If the DTS-10 was still available as a kit, I'd recommend that one.

These DIY sub designs are more than just cost effective--I built my two SPUDs for a little less than $500(US)--but their output eclipses direct-radiating subs. I power them with Crown XTi-1000s, which provide plenty of power and have built-in DSP to do parametric EQ, delay correction, and crossover filtering.

Chris

[psg]

I agree with Chris. In such a large room, you need to think really big in terms of subs. DIY is not doesn't have to be expensive but takes time.

Also, for such a large room, it would be a good idea to audition some big Heritage speakers from a fellow forum member.

[Audible Nectar]

Agree with Chris - and agree with psg: That room sounds like it screams for Heritage. 6 LaScalas + Danley DIY sub = Upgradeproof speaker system, and can be done without busting the budget, too.. If that's a room/dwelling you plan to be in for the foreseeable future, take a step back, breathe, and consider what it would take to do this ONCE - and make you happy in that room for life.

Great speakers make for a great system. There are a host of options for the electronics that doesn't have to be highest end, but good value choices that could make that a colossal installation.

I put five Cornwalls and two JBL pro woofer cabs in a 20x14 (yeah, it's overkill) and know that I can die with this kit.

[nezff]

I would not waste my money on upgrading to the SVS. They get great reviews, but with a room as big as yours, DIY or other ID sub comapnies would be a far better bet.

[JasonJCarney]

I would keep the front 3 and upgrade the sub. The sub is your choice but IMO the sub and center is the most important speaker in your system.