First theatre- Ascend seems to be for me

[chas]

If you will be placing your center speaker on top of a TV (and not on a stand), you may want to read the EXBAC Defined section on this page:

http://www.ascendacoustics.com/pages...t340ctech.html

[bikeman]

Thought I'd found the article that Curtis mentioned but it wasn't the case.

David

[Kurt C.]

Kurt...if you do a search, DaveF has a pretty detailed post of the differences between the 340 and 170 and he also references the Cumulative Spectral Decay graphs.

Thanks. In the course of my search, I found the answers to a couple of questions that I raised earlier. First, What has been done to the CMT-340 center from an engineering standpoint to minimize the problems inherent to using an MTM speaker on its side as a center Dave F. explains and specifically, would the 340s or the 170s be a better choice for the HT under discussion Dave F.s recommends 170s for a 15x15 room

I haven't found the answer to whether, in a small room, it would be better to use a 170 center (that avoids the whole off-axis MTM problem) or a 340 center (optimized to minimize the MTM problem). Can anyone direct me to a thread where that specific question was addressed?

[curtis]

Maybe I should work on getting all of DavidF's technical posts into one place. Didn't I post that before?

[Quinn]

This was posted by Dave F. in an earlier thread.


It is certainly OK to prefer the CBM-170 over the 340 main… both speakers were designed for specific purposes and what sounds best to you is purely subjective.

From a technical standpoint, the CMT-340 is superior… The CBM-170 uses a single high performance woofer while the 340 uses two. In any loudspeaker, distortion increases as output increases. Depending on how you look at it, the 340 has the capability to deliver either twice the output of the CBM-170 at the same distortion level, or close to half the distortion at the same output level.

The tweeter used in the CMT-340 is also technically superior, having lower distortion, a lower resonance frequency and extended high frequency response.

We actually post a very revealing graph on our website called the cumulative spectral decay. This is seldom understood, but still a highly important measurement. This is a measurement of a fast impulse consisting of thousands of frequencies ranging from 400Hz to 20Khz. What the graph reveals is what “noise” is left over once the initial impulse stops (in milliseconds). Notice on the 340 graph that there is very little (if any) artifacts left over after 1.92 ms past 2kHz (this is really amazing actually). On the CBM-170, there are artifacts between 2kHz and 5kHz almost reaching 3.5ms (about half that of the 340, which is still, quite good). Also you might notice more artifacts in the high frequency region as well..


CMT-340 cumulative spectral decay



CBM-170 cumulative spectral decay


From a purely objective perspective, the 340 is a more transparent, more revealing speaker and I believe this is what you might be hearing…

Hope this helps! __________________
.

[bikeman]

This was posted by Dave F. in an earlier thread.
Hope this helps! __________________
.

This is what I posted and then deleted. There was another Dave F. post that I thought was an answer to Nicholas when he was discussing using the 170 as a center. I tried to find it but was unsuccessful.
Maybe when Nicholas stops working 20 hours a day to pay for his home theatre, flying lessons and half the land in western Massachusetts he'll be able to point to that post.

David

[Prairie]

Wow, I didn't expect this to turn into a debate...cool

So, about the surrounds...any opinion on that?

Looks like i'll have to do some reading to figure out what I want to do for the center.

[Eddie]

Kurt,

so if I were to take my 340c and stand it up I should notice some slight improvement (though I understand it has been designed to minimize/reduce the disadvantages of lying down lengthwise)?

I guess I tend to favor the 340c over the 170c just because, as David F. writes, its extra driver allows for double the input of the 170s, and because I consider the center to be the single most important speaker in HT since it handles dialogue which comprises at least 60% of most movies so the more dialogue output the better, I'm not into bam-bang-boom movies so clear natural dialogue for me is a much higher priority. I'll confess to having zero scientific evidence to back any of this up with, though.

I guess overall I simply have doubts about how much of a SIGNIFICANT difference going 170-170c-170 makes vs. 170-340c-170. I don't doubt that there may be SOME difference, but would be highly surprised if it were in any way significant as long as you weren't listening super-closely in anticipation of hearing that difference. The other reason for my reservations about doing all 170-170c-170 is my judgement that the extra output of the 340c is worth any insubstantial compromise in SQ. Of course we'd have to come to a universal definition of "significant" and "insubstantial" first, lol.

I guess lately I've become a bit of an audio skeptic beginning with my recent auditioning of higher end CD players that to my ears made only very subtle differences at significantly higher prices. Recently I got an all-digital Onkyo TX-LR552 that Fry's closed out at $100 and have been struggling to hear a huge difference in SQ between it and my NAD, though a much more audiophilish friend who dropped in for the comparison swore it was a night and day difference (in favor of the NAD). He's going to come back for a blindfold test next week, which should be very interesting. Right now I'm trying to shake off the creeping suspicion that we audiofans spend way too much time splitting hairs!

[Quinn]

This is what I posted and then deleted. There was another Dave F. post that I thought was an answer to Nicholas when he was discussing using the 170 as a center. I tried to find it but was unsuccessful.
Maybe when Nicholas stops working 20 hours a day to pay for his home theatre, flying lessons and half the land in western Massachusetts he'll be able to point to that post.

David

Is this the thread and post you were looking for? http://forum.ascendacoustics.com/sho...86&postcount=3

Thread- http://forum.ascendacoustics.com/sho...sient+response

[bikeman]

Is this the thread and post you were looking

Yes. I think I was combining both threads and thinking it was one.
Thanks, Quinn.

David