Definitive Owners Thread - Page 878

So, you would be averse to getting even more and even better performance out of your "mega amplification"?

[quote=sivadselim;21858879]I told you the "point". Among other things, it reduces the load on the AVR's amplifiers considerably, allowing the amplifiers to more cleanly amplify those frequencies they ARE asked to amplify.

Have you tried a 40Hz crossover with the speakers you are running full-range?

Regarding the "sound your (sic) getting", the sound you're getting may have as much or much more to do with your room and exact settings (i.e., a tower's sub's volume setting, among many other things) than it does with the crossover point you are or are not using. Definitively determining that you prefer running the speakers full-range over crossing them over would require carefully making sure that you eliminate or reduce as much as possible ANY other variables which are affecting the results. And there are PLENTY of other variables, here.[/QUOTE

Your point sounds like its all about efficiency not sound quality.. Why does def tech tell us to run our speakers large then?

It's ALL about sound quality. Do you understand how relieving an amplifier of having to amplify the lowest frequencies, which place the most load on an amplifier, can increase the available headroom and improve the sound quality?



As I said in a post a few up, I understand that powered speaker owners are in a unique situation. However, I believe someone from DefTech, a few posts further up from that, still recommended using a 40Hz or 60Hz crossover. I'm not sure exactly which speaker models he was referring to, though.

Remind me what speakers and sub(s) you have, LowTech1.

it's only a "benefit" if you need the headroom

if you're not getting distortion or your receiver isn't shutting down, it's a non issue

like i said. my receiver has bass management. it came with it for free. i have tried it

It has nothing to do with needing it. Everyone can potentially benefit from the increased headroom and cleaner output. And it IS free.

You must admit that your system, assuming it is what I remember it being, is more than unique. If you are still running a dedicated subwoofer on every speaker channel, then the desire to run every channel full-range is understandable.

The def tech guy recommended using a diff crossover to get the right sound. Not that is was bad to run it full. I have 8060ST's,8060HD center 8040 surrounds. A Klipsch 12" sub.. Soon will be replaced by an SVS PB 12 NSD or a HSU VTF-3 MK4 sub..

This makes sense, especially with the exception/caveat for powered towers.

For those not following, here is my attempt to paraphrase what sivadselim is saying.

Bass frequencies require more power than the rest of the signal, reducing the amount of headroom available for other frequencies. This applies to all speakers and designs. A separate powered sub reduces the amount of headroom being used by the amplifier/AVR on bass, which can have a positive effect for the rest of the audio signal as it is less likely to run out of headroom/clip/distort.

In powered models (7000's, Mythos ST/STS, 8060's/8080's, etc) the bass signal is already sent to an external amp from the AVR,those within the towers. This is part of the exception sivadselim was mentioning.

In non-powered speakers, the bass frequencies eat up the most available power power from the AVR/amp, which can limit both the output and the sound quality of your speakers if you run them full range. Relieving the AVR/Amp of these requirements allows it to run with more headroom/stay within its limits more easily, which can improve the SQ.

The concept is the same for both types of speakers, off loading the power requirements of the bass frequencies from the AVR/amp that drives the rest of the signal. Having subs (internally located and powered or external/separate devices) handle the most power hungry part of the range also allows the amplifiers that drive the remaining portion of the signal to stay comfortably within their limits, avoiding clipping, distortion, compression, loss of dynamics, etc. This applies whether you are using separates or an AVR as the concept is the same, but the lesser the amplifier capability the more beneficial it would be.

Even with powered towers though, the powered bass section rolls off below a certain point (which many of them do, for example my STS's pretty much run out of steam in the low 30 HZ region). Having the deepest bass (say below 40Hz or 60 HZ) handled by a dedicated device, your subwoofer, makes sense as it is quite possibly more powerful than the internal bass drivers. It again has its own amplifier, and depending on the design the enclosure will have more volume, the driver will have greater excursion, etc., which will lead to a design more capability for these frequencies and the SPL/output to recreate them convincingly. Additionally, a sub allows you to place it in a different location from the mains that may work best for bass, but not for the rest of the frequency range, which is quite common in most rooms.

So not running the mains as full-range speakers (crossing them over to a dedicated sub) allows the system to better utilize its components, such as dedicated, well placed subs handling the deepest bass, even for speakers with powered bass sections.

Hopefully I haven't further confused anyone or misinterpreted what sivadselim was saying.

i don't think powered towers or using a sub on each channel effect the theory sivadselim is talking about. if your channels are set to "large" the amp in your receiver is still "seeing" a full range load and i believe (i could be wrong here, i'm going by distant memory) will not get the "benefit" of the added headroom. you would need to engage bass management to see this potential benefit

either way it doesn't effect me personally

Right. My main point of posting here regarding this is that doing these sorts of comparisons PROPERLY is not at all trivial.

Right. There is no difference at the level of amplification.

But there are, of course, benefits to be had when using conventional non-powered speakers, at the speakers themselves, when using bass management. But powered towers, particularly larger ones, don't really get or even necessarily need this particular benefit. And that, coupled with their usually more capable low-end performance, sort of present a Catch22 regarding exactly how to utilize them in a HT setup. I understand the desire to set them, particularly the larger ones, to run full-range.

Well I'm telling you,with the speakers in full range it sounded noticeable better. Also,you talking about the sub being self powered,thus it would take some of the overhead off the amps. The 8060's have amps built into them for the subs. They shouldn't be drawing power off the amp except for the tweeters and mids. right?

I understand. But I would question how rigorous your comparison was in regards to removing all the other variables involved. And there are MANY variables involved, here. No, I'm not suggesting that you expend a lot of effort trying to make this comparison. Only that you be mindful of this when interpreting your results.



The AVR's amps are still amplifying a full-range signal.

There are so many ways to setup the audio portion of ht's it's almost insane. 5-11 channel, receivers, seperates, no sub, 1 sub, 12 subs, small satellites, huge JTR triple 12's etc. I have done a lot of experimentation with my system and just went with what workes for me in my room. None of my 7 channels of amplification have to produce anything under 40hz. I think that is a bonus. I am very happy with my current configuration and don't feel the need to change anything. I can finally enjoy music/movies without wondering "what if I..."

I will do more comparison's tonight. Why would sending a full range signal matter. The subs are like an external sub. They have their own amps. Hell,the towers amps(300 watts) are more powerful than my Klipsch sub (105 watts).. If I had a more powerful sub,then this might be a non issue.. But then why even buy speakers with powered subs in them.. What's the benefit?

I'm not sure what you are asking. Sending a full-range signal is not what matters. It's that the amplifier is amplifying a full-range signal, anyway.



Right, and this may well be one of the main reasons why you prefer running the speakers full-range.



Exactly. You might find that you preferred sending some of the main channels' bass to a more capable subwoofer.



Well, that's the question I would ask. For HT, with adequate subwoofers, I think their benefit is questionable. IMO, they present a bit of conundrum for HT use.

Everyone's situation is different. I found sending anything below 40hz to my 7001's seemed to strain them, the bass got bloated. With all due respect to Definitive, their powered sub in the towers are good but not the same as an outboard sub. Many of us have expressed an intrest in them reviving the bipolar towers MINUS the subs (i.e. bp30's.) We feel they are the best value in the bp lineup.

In my case, I liked the sound of the rest of the spectrum better that the non-powered versions (say the Mythos One's vs my STS's, and the 8060HD vs my old Mythos 10), they had better midbass punch, with a fuller sound, to my ears. I cross my speakers over at 100HZ to my subs, dual SVS PB13-Ultra's, which are considerably more potent in this range than the towers/center.

That said, out of curiosity once I tried using my Gem XL's as mains crossed over at 100HZ and 120HZ and felt they were lacking. Crossovers aren't a brick wall after all, and the added capability is still there, just not as pronounced as when no subs are being used.

IDK,it just sounds to me anyhow that when the subs in the towers are used they sound a lot better. I turned them all the way down and there way no midbass at all. If anything,those subs act as your mids..

That's what matters most, it is your system. Set it up and play it as you like.

What are you guys running for speakers.. I need to get some pics up under my profile.

http://www.avsforum.com/avs-vb/showthread.php?t=1193082

Bartman,I've seen those pics before.. Your taking this hobby to another level..LOL

Sorry, I didn't realize. I've been at this a long time. My first "ht" was a dolby pro logic setup with 5 mismatched speakers, about 20 years ago. Made a few changes since then.

Consider the possibility that a sub asked to do nothing but produce LFE signals might yield a cleaner low frequency output as well.

On a completely different note: Has anybody used a CLR 2002 instead of/or also a CLR2000 with their 7000's or 7001's?

Yep. A lot of stuff to be considered.

In the 90s, before Dolby Digital, in the good ol' days of Pro Logic, I had a pair of powered towers and quite liked them. Although subwoofers were certainly around, they were not nearly as common, then, as they are nowadays. There was no LFE channel. AVRs were not capable of bass management and they didn't have a dedicated subwoofer output. If you used a subwoofer, it was simply used to augment the front speakers' output.

But, I actually like the idea of powered towers. And even though I wouldn't necessarily call the two incompatible, I think the bass management philosophy of modern AVRs is different enough to present a bit of a conundrum when using powered towers in a HT setup. If I had a pair of capable powered towers, now, along with a capable subwoofer, exactly how to configure my AVR's bass management would probably present an issue for me. I suspect my thought process would go something like this:

"Gee, I have these very capable speakers, capable of solid output down to 30Hz (maybe further) and I paid for their powered subs. I am really going to have a hard time not using them to their full potential.

Conversely, I have this very capable subwoofer and an AVR that is capable of all sorts of bass management configurability (not to mention the very fancy and capable auto-EQ), it would be a shame to under-utilize this expensive subwoofer and AVR."

Coupled with knowing how hard it is to really, fairly make the comparison of the two options (and it's really more than two when you consider the different crossover settings available), the decision would probably create some angst for me.

I think it does for some people like myself.. If using the subs in the towers provides no benefit,I should get diff speakers.. maybe the subs are for people without the room for a real sub.. Who knows..

Def tech with powered subs is a hit or miss.
If your towers are in the right place, the subs will sound just right. Otherwise you might end up with a separate sub that you can place it in the sweet corner.

Having went through the cycle of "why would you need a sub with a powered speaker" to "let's treat my Mythos ST as two front subs and manage LFE with bass EQ" and finally "I have two Hsu subs''; the ST are for mid-bass in an Audyssey Pro calibration" in less than a year, here's my $0.02:

If you're in a small room (call it < 1500 sq. ft) and not particularly picky about how deep or how accurate lower bass and LFE are, a Mythos ST or BP supertower without a sub will work. You might as well run them as Large with a 2.0 system unless you want to do a subtle tweak to the level of sub volume, you're a tweaker, or are savvy about bass management with an HT system. At which point getting the CS series powered center makes sense to get a well-matched front setup.

However, if you care to the point that you're thinking of an external sub, and realize that the powered DefTechs aren't designed for truly low bass (<40 Hz at -3db unless you have just the right room), then you let the DefTechs handle the >40 to 80 Hz as well as they can with at least one (preferably two) standalone real subs. In that case, the main value of the powered woofer section is the ability to control the bass volume on the DefTechs to get a) a flatter before EQ response and b) to better manage level matching betweeen the speakers. Also, if you're concerned about even room response, the powered section, along with one or more real subs, come in handy. It may save you having to have two or more real subs to go with your setup. I know that if I didn't have the Mythos ST and had, say, Martin Logans, I'd possibly go to three or even four subs rather than two I have now, in a 4000+ sq ft. room.

Another observation, which some may disagree with: I found that when I had MCACC + a standalone bass EQ, being able to turn up the mains' bass on the actual speaker during level matching was handier than when I moved to Audyssey XT32 and the Pro world. However, I personally feel that bass, even if 'non-directional', feels a little more lifelike if the midbass is coming from a speaker rather than a sub. So ultimately powered speakers are worth it because of the overall flexibility they give you, sub placement issues and RC aside.