Sierra-1 Nrt vs CMT-340 for DEDICATED Home theater

[j0nnyfive]

I am reading about Dolby reference levels and articles discussing whether theaters are too loud. Hmm... I may NOT shoot for "reference" after all! I didn't realize how loud this really is. They say it has possibly increased over time. Not sure though. Doing research.

[milkfat]

Dolby reference level specifies that each speaker must be capable of producing 105dB at the listening position. The subwoofer must be capable of 115dB at the listening position. All channels driven equals (I think) a peak level of 120dB .

I think a reference level system is a nice goal. You don't always have to listen at reference levels. Certainly you should use common sense and adjust the level on a movie-to-movie basis.

Here's a nice calculator that lets you enter in a few numbers and see the dB capabilities at listening position.

http://myhometheater.homestead.com/splcalculator.html

For example: the Sierra-1 (87dB) requires ~3 times more amplifier power than the CMT-340 (92dB) to produce the same level of output. Then there is the fact that the CMT-340 has much more driver surface area - possibly meaning that it is more capable of producing the lower frequencies (near 80hz) at high levels than the Sierra-1. I'm not sure about all of the qualifications for that last statement though.

[scape]

i think total driver excursion should be taken into account, in addition to total surface area. there are many 'long-throw' woofers that simply out compete standard larger sized woofers. it would be interesting to see a sierra with 2 woofers, that's for sure, but i guess that's what sparked the tower.

j0nny, after looking at the part where you said a center channel is not possible due to location, as well a subwoofer is not ideal due to you being in an apartment; I imagine an amp would do your system justice. have you looked at any amps as of yet? there are a ton to pick from. it is possible that an amp will improve dynamics and headroom if you're stepping up from your avr's amp.

[j0nnyfive]

Milkfat,

I just got back from a speaker/home theater store in a nearby town and they let me bring my radio shack spl meter in to one of their little theater rooms. Holy crap 105 dbs was L O U D. lol Geeze.. I don't think I'd ever use it that loud... but then again, it would be nice to have a system that COULD... you know... just in case. tee hee!!

Scape, you know... the amp may be just what I need for my next step. I haven't given it much thought yet tho. Even though I can't really turn it up to any significant volume, would having some sort of amp give me a noticeable improvement in quality? I guess it would be nice to have that overhead... you
know... just in case. tee hee!!

sorry. I'll stop cackling now.

Today I have been playing with my new toy (spl meter). I would like to determine what the highest volume I can have my receiver at during a movie without it clipping. How would you do this? I'm thinking some sort of standard test tone that is meant to play at the loudest sound possible and then I can just slowly turn the volume up until my SPL meter reads whatever I think it should read as determined by my speaker sensitivity and receiver's power rating? Not sure... going to sleep now. Really tired right now...

Thanks for the replies!

[scape]

i think denon's use compression to limit any sort of clipping, so you'd hear compression first- which is more difficult to discern by itself, i'd say.
a test tone wouldn't exactly be best in my opinion, mostly because you do not listen to test tones- but rather most of the audio spectrum during a movie. i'd pick some music with mostly constant full range (jazz and electronic are good in my opinion) and begin testing for distortion and compression by ear. compression will sound as you hit the compression wall that certain parts of music are no longer getting louder, and may even sound muffled to make up for the other parts; typically midrange suffers. there is probably a good article or how-to out there. since you have an spl meter you could test for your assumed max spl output based on what you already know: speaker sensitivity, number of speakers in conjunction, seating distance, and amp output. once you hit what you think would be your max you should atleast begin hearing something happen. i think denon is pretty smart when it comes to overcoming limitations such as amp power, and they may have a pretty advanced compression algorithm to take care of it- so it may take a few songs or movies before you realize where it begins.
as for amp types, a lot of people put faith in certain brands or types (class a/b etc) and I think at the end of the day the amp just needs to do its job and amplify without mucking up the signal too much. i'd personally stick to mainstream brands and not an ID company, call me crazy but i'd want the amp to be bullet proof and tried by hundred of thousands of users, not just thousands.

[j0nnyfive]

Scape,

Good points. Thanks for your help! I have been uber busy the past few days so I haven't had a chance to post. I have decided to just stick with my system as-is right now. (2 Sierra Nrts and my Denon receiver). In this apartment, this sounds AMAZING. My buddies came over the other day and after we left one of them said "Your surround system is awesome". lol When I told him it was just 2 speakers he was pretty stunned. My Mom and Dad came over and had a listen and they were both impressed I think! I'm trying to piece together a good setup for my Dad at the moment. I will post this in a new thread.

Thank you all for your input! I love this forum. Thanks!

[scape]

sweet, keep us posted!

[cynan]

Yeah. 105 db is loud. 99% of my listening is below 90 db and most of that is probably around 80 db or or less.

On a related note, it's kind of funny how my girlfriend loves to go see movies at the theater: Occasionally I find some movies to be a bit too loud. When I mention this, she shrugs. (She also used to love to go to concerts all the time.)
However, if I try and play a movie (that we are both watching) at anything close to those levels at home (in actuality probably a good dozen db lower), she complains that it's too loud.

Maybe she's just not a fan of Ascend speakers

Scape,
Good points. Thanks for your help! I have been uber busy the past few days so I haven't had a chance to post. I have decided to just stick with my system as-is right now. (2 Sierra Nrts and my Denon receiver). In this apartment, this sounds AMAZING. My buddies came over the other day and after we left one of them said "Your surround system is awesome". lol When I told him it was just 2 speakers he was pretty stunned. My Mom and Dad came over and had a listen and they were both impressed I think! I'm trying to piece together a good setup for my Dad at the moment. I will post this in a new thread.

I really like my Sierra NrTs with my Denon AV receiver too. Before I upgraded to NrT, I used to go through the hassle of switching to my 2-channel amp (Virtue Sensation) for music all the time. With the NrTs, I feel less compelled to do so. It just seems that the Denon and the Sierras are now a bit better match than before the upgrade. Or maybe I'm just getting lazy... And the NrTs sound so good that even a lesser-sounding amp is more than good enough.

Edit: @j0nnyfive: Just wanted to add that my Denon is only rated at 105 Watts per channel into 8 ohms for multichannel and about 130 watts for 2-channel and it's more than loud enough with my Sierras (in about 500-600 or so square foot space, at about 8 to 10 feet away from the front speakers). Just because the Denon starts at -60 (or whatever) and you have to get to -20 before it gets to a "reasonable" volume is not something to worry about. When listening to movies at a level at the very loudest that I like it, I would never go past -10. Normally, I'll listen closer to -20. And, theoretically, the receiver should handle the 0 volume level just fine. If you do not find the levels to be very loud at -10 in your small space, perhaps check your source. For example, if you are playing Dolby or DTS tracks from a computer and are not using bit-streaming (ie, the computer decodes the audio tracks instead of the receiver), this can cause a drastic reduction in volume - I ran into this myself with Widows Media Player Classic. If the Denon is set to bitstream, it will indicate "DTS" or "Dolby Digital" or whatever on the display. Otherwise, it will indicate "Multichannel" or "PCM" if I recall correctly.

When you do move into a bigger space, you can worry about having enough volume when the time comes. But unless your listening space is quite large, I would think the Denon should be up to the task with the Sierras.

[j0nnyfive]

Thanks for the reply Cynan!

That's funny about the relative loudness thing. I think sometimes we psychologically accept things as "okay" in on setting but then our brain says stop in another setting. Like, the theater volume is okay, but at home it just SEEMS too loud because of where we are. My theory anyway.

My source right now is my PS3. Great bang for buck, btw. For 300 bucks you can't get much more in one machine I think.

Now having watched several movies on the Sierras, I think a large part of my volume concerns has a lot to do with the recording/mixing of the movie itself! I think some movies are just made... badly. Dialogue in some scenes is just hard to hear but the music in the background is louder than it should be. To my ears anyway. But in a different scene, the dialogue is perfect (slightly too loud), etc. I'll pop in another movie, and it won't have that problem. I'm starting to see the differences in how the sounds are put together for different movies. I like how the Sierras allow me to hear this level of detail. Now, when I say different movies, I mean movies from the 80's, then 90's, then past 2000, etc. But, yeah, I think the Sierras are very much up to the task of HT. Very much so. I'm listening at about -25 on average now I think. I turn it from -30 to -20, sometimes a bit higher, depending on the scene.

[davef]

Now having watched several movies on the Sierras, I think a large part of my volume concerns has a lot to do with the recording/mixing of the movie itself! I think some movies are just made... badly. Dialogue in some scenes is just hard to hear but the music in the background is louder than it should be. To my ears anyway. But in a different scene, the dialogue is perfect (slightly too loud), etc. I'll pop in another movie, and it won't have that problem. I'm starting to see the differences in how the sounds are put together for different movies. I like how the Sierras allow me to hear this level of detail. Now, when I say different movies, I mean movies from the 80's, then 90's, then past 2000, etc. But, yeah, I think the Sierras are very much up to the task of HT. Very much so. I'm listening at about -25 on average now I think. I turn it from -30 to -20, sometimes a bit higher, depending on the scene.

Honestly, you should really find a way to integrate a center channel into your system. It will make a HUGE difference