Advantages of not using a subwoofer

[robruffo]

I think this is an important issue.

Using a subwoofer, it seems to me (and no matter how great it is) brings about many problems:

1 - Integration and placement are non-obvious. You fuss and fuss and always wonder if you got the room placement and levels right. If the bass is crossed-over and its levels set inside the speaker by a talented designer like David, then you can just sit back and enjoy and not worry that it is too high or low compared to the rest.

This perfect sub placement, if if it were achieved, seems also to be more listening-position sensitive (there are always still many points in the room with too much boom relative to the sound coming out of the mains) , whereas bass coming from mains is distorted evenly as we move to non-optimal listening spots, along with the other tonalities, in a smoother, more natural way. So the group of all tonalities in a "bad" listening spots, when getting bass only from the mains, sounds bad/wrong in a way that is more psycho-acousticaly acceptable, it sounds more "normal".

2 - Yamaha and other receiver brands have a pure-direct (essentially pass-through with neutral unprocessed amplification) mode which circumvents receiver circuitry and tends to give a more detailed and artifact-free sound that is truer to the source. The problem is, this mode, in most brands, also stops crossing-over to the sub. So you are left with a choice - get all your bass from the mains or use teh sub and lose detail.

3 - Most subs are not as fast/detailed as bass emminating from a great speaker like the Sierra. Sealed designs tend to be more musical, but the Sierra's bass will still beat just about any sub in tightness and precision, hands-down.

This may be an incomplete list, and I'd love to hear comments.

Here is one advantage I've heard (which may be a myth - let me know if you think it is) of using a sub: It frees up your mains to focus on less range, and therefore do a better job of that more limited range. I'm not sure if this holds true for somethig like the Sierras, but I'd love to know.

[MikeS]

Integrating a subwoofer into a system is not always simple but it certainly can be done with a quality subwoofer and some patience. Setting the level is not too difficult if you have an spl meter. Some people, myself included, use the BFD to take measurements and EQ our subs.

Once you have the bass well integrated, it should sound like most of the bass is coming from your main speakers. If you can tell that all the bass is coming from a sub in the corner, then it is not well integrated. Many manufacturers encourage the use of subwoofers and say that "the best placement for you main speakers is often not the best location for bass."

It's true that the Sierras have quite detailed and extended bass and is better quality than many subs. However, there are subs that are just as detailed and have far more extension and output capability. My JL Fathom sub would be one of them.

The advantage of using a sub to relieve the main speakers of bass duty is huge especially if you like to listen at higher levels. The small woofers on the Sierras can only move so much air and when you get down that low, you will run into issues like THD and port noise much sooner if you aren't using a subwoofer.

[azanon]

I've just seen one too many audio guru's/geeks (I mean this with love) say that most people should use a sub. I put blind faith in them, and choose to follow that advise.

But, for what its worth, I've tried it both ways and "with sub" sounds better to me. Then again, I use 340SE's for L/R, not Sierras.

I'm sure not using a sub theoretically has one, two, or a few "advantages". But If the experts are right, this list should be shorter than the disadvantages.

[DougMac]

A common crossover point for subs is 80 hz. THX did hearing tests of hundreds of people. Most lost the ability to discern direction a littl north of 100hz. 80hz was the highest frequency at which no one in the sample could discern direction, hence the convention.

How much musical content is there below 80hz? How much is fundamental notes and how much is harmonics? From what I've read, there's a fairly small percentage below 80hz, but my listening tests indicate there's more down there. Even using speakers that test out far south of 80hz, adding a sub can add a fullness to music with a double bass or similar instruments.

As mentioned, integration can be problematic. 80hz is not a brick wall. Even with steep rolloff curves, there's significant audible content above that coming from the sub. I'll leave the numbers to the math wiz's, but consider this. 160hz is one octave above 80 hz. If your system rolls off 12db/octave, what is the db drop at 1/3 octave? I'm guessing it's still pretty high. How the output of the sub at 100-120hz interacts with the output of the main speakers, which should have plenty of output in that range will have a pretty significant effect on sonic quality. Please forgive my tenuous grasp of the technical. Those who actually know what you're talking about please step in and correct.

I got a practical lesson in this just yesterday. I have Boston Acoustics CR9's in my living room along with an older Infinity Servo Sub. I just bought a used pair of "classic" HTM-200's and did a quick test. These little speakers put the much larger CR9's to shame. The most striking difference was low bass, which seemed counterintuitive since the CR9's have much bigger woofers. It's like the 200's woke up the sub. I even tried reversing the polarity of the sub when played with the CR9's. It didn't help. Go figure!

Lastly, I've long accepted the axiom of less it more in speaker drivers. I tend to agree with those who descibe the ideal speaker as a two way woofer/tweeter array. Adding a sub is adding another driver to the mix, along with the subsequent problems.

Doug

[Galwin]

I found that crossing my sub ar 80hz with the Sierra's resulted in a deterioration of the 3D imaging - one of the speaker's greatest strengths. Switching to 60hz, per the recommendation of Curtis, solved the probelm. I don't understand why it would make such a difference, but it did in my room.

It seems to me that bass managment is easier with a sub than with tower/full range speakers, especially in small/medium sized rooms. Your options for placement and speaker adjustments to integrate bass into the acoustic envrironment seem much more limited with a full range speaker.

[curtis]

Your options for placement and speaker adjustments to integrate bass into the acoustic envrironment seem much more limited with a full range speaker.
That is the key statement.

The best location for the sub(source of bass in a room) is usually not the same location where you have your main speakers.

Even full range floorstanders benefit from the use of a subwoofer. I addition to placement options, it allows the woofers to do less work.

I agree the Sierras have excellent bass qualities, and if one were to use a subwoofer with them, it would be important to get one with matching sound quality.

[BradJudy]

1 - Integration and placement are non-obvious. You fuss and fuss and always wonder if you got the room placement and levels right. If the bass is crossed-over and its levels set inside the speaker by a talented designer like David, then you can just sit back and enjoy and not worry that it is too high or low compared to the rest.

While level and phase integration are additional complications to a subwoofer, adjustable room position is a benefit. You had no chance to position the bass in a tower in any other location. You can place a sub right under a bookshelf speaker and see if it sounds best in a quasi-tower arrangement.


This perfect sub placement, if if it were achieved, seems also to be more listening-position sensitive (there are always still many points in the room with too much boom relative to the sound coming out of the mains) , whereas bass coming from mains is distorted evenly as we move to non-optimal listening spots, along with the other tonalities, in a smoother, more natural way. So the group of all tonalities in a "bad" listening spots, when getting bass only from the mains, sounds bad/wrong in a way that is more psycho-acousticaly acceptable, it sounds more "normal".

This doesn't make sense to me - I'm not sure what you're saying here.


2 - Yamaha and other receiver brands have a pure-direct (essentially pass-through with neutral unprocessed amplification) mode which circumvents receiver circuitry and tends to give a more detailed and artifact-free sound that is truer to the source. The problem is, this mode, in most brands, also stops crossing-over to the sub. So you are left with a choice - get all your bass from the mains or use teh sub and lose detail.

There are various non-DSP sub integration options. Almost everyone using a sub in a purely two-channel setup does something like sub integration with the natural speaker roll-off or an analog crossover circuit.


3 - Most subs are not as fast/detailed as bass emminating from a great speaker like the Sierra. Sealed designs tend to be more musical, but the Sierra's bass will still beat just about any sub in tightness and precision, hands-down.

Have you tested the Sierra with "just about any sub"? That's quite a statement to make.

[robruffo]

Have you tested the Sierra with "just about any sub"? That's quite a statement to make.

I don't mean the very best of best, but the majority under $1600 or so, and the totality available at big box retailers. You're right my wording was fool-hardy.

I guess my conclusion coudl be better stated as: You need to spend a lot of money, while listening to music on an HT receiver, to improve on the bass provided by Sierras. If you spend less than that (unless you have access to a yummy super-deal like the recent limited-edition 50 unit HTR subs that Rocket was offering) your sub will likely make things worse. As such, Sierras are an economical way to get very good (maybe not as good as a Fanthom but...) bass. To improve on their bass offering for music woudl cost a lot more via a sub than say the difference beteeen a 340se and a Sierra pair.

[robruffo]

One last comment...

Those of us using home-theatre set-ups, and/or set-ups for 5.1 SACD and music Hd-DVD/Blu-Ray rather than old-school stereo-only do not have as many optiosn possible. You basically use the receiver processor (and lose detail), or you bipass it (and lose the sub, albeit in the case of SACD often the lfe channel contains what it should.).

I know some receivers offer more options, such as Pioneer, but this is the choice within many brands and models.

Again, we must consider economics. Buying a new receiver or a pre-amp or any other piece of high-grade equipement to make a pure-direct with sub situation possible, without losing lfe use of said sub in 5.1 uses, costs way more than upgrading to Sierra from 340se.

[MichaelG]

I'm no expert and only have my speakers to compare. When I had 340's across the front, I felt my HSU 3.2 was a beautiful complement. After upgrading to the Sierras for L/R I now feel that my music is awesome without the sub turned on. If the sub is on I set the crossover to 50hz on the Sierra's because I think I feel more of the kick drum.

If I mainly listened to music and had limited dollars, I would buy the Sierra's first with no sub vs the 340's with one. However, if I watched movies most of the time and liked that deep bass I would opt for the 340's and sub. The Sierra's are awesome but can't shake the room during War of the Worlds like the HSU.

All that said, I only have my sub placed near the corner and level set with a SPL meter. I'm willing to bet there are many here that could do a better job of placement and integration.

[BradJudy]

Those of us using home-theatre set-ups, and/or set-ups for 5.1 SACD and music Hd-DVD/Blu-Ray rather than old-school stereo-only do not have as many optiosn possible. You basically use the receiver processor (and lose detail), or you bipass it (and lose the sub, albeit in the case of SACD often the lfe channel contains what it should.).


Actually you do. You can configure the left/right as large and no sub, then route the left and right pre-outs to the sub(s) instead of using the sub-out. The pre-outs will still work in direct mode.

If you're really into subs, then use two, one for the lower part of the mains as described above and another for the LFE only. You could route all three signals to one sub, but you'd have to use the sub's built-in crossover for the L/R signal which would probably be lower than the setting used for the LFE crossover, creating a gap in the LFE output.

And there are definitely subs under $1600 that match fine with the Sierra's. My ACI Titan XL is one, I expect the Rythmik servo that someone here has does quite well. Many here pair them with sub-$1k Hsu subwoofers.

[robruffo]

Actually you do. You can configure the left/right as large and no sub, then route the left and right pre-outs to the sub(s) instead of using the sub-out. The pre-outs will still work in direct mode.

If you're really into subs, then use two, one for the lower part of the mains as described above and another for the LFE only. You could route all three signals to one sub, but you'd have to use the sub's built-in crossover for the L/R signal which would probably be lower than the setting used for the LFE crossover, creating a gap in the LFE output.

And there are definitely subs under $1600 that match fine with the Sierra's. My ACI Titan XL is one, I expect the Rythmik servo that someone here has does quite well. Many here pair them with sub-$1k Hsu subwoofers.

Pair up with fine, yes, but do these subs offer as quick and precise a rendition of the 40-80hrz range, not really. Plus... Once again we have a much more expensive solution than simply getting Sierras over 340se s (my main point here) plus you can still integrate a sub later, and plus the Sierras are better in other ways. In other words, extra money spent on Sierras is an excellent low-budget investment in the goal of refined, musical bass, far better than a cheaper sub.

I've recently heard lower-budget HSU subs. They're very, very good, but they still, in my opinion, sound like subs, not like blended bass coming from a speaker, as is the lower range of the Sierras (the person who owned them is quite a pro, and integrated them quite perfectly - he even has some room treatments). If you want super-tight bass from a sub, you really do have to spend quite a bit. (Again, the one exception being sealed Rocket (AV123) units - which are not very loud, but with the new 500 hrz amp do apparently go down to below 20hrz quite cleanly. New models like this will be available soon (not sure how soon). They sold me one of the 50 units made so far - I'll let you all know how it measures up when I get it.)

I realize the above solution is possible (one sub for each app), but TWO quality subs is a lot of money for many people. Plus, running LFE AND crossover I think might cause problems, as the sub would be getting the same signal twice. I'm not sure, but I think I've read that's a no-no. If anyone wants to correct me, please go ahead. I also think some subs will only accept one signal at a time automatically to protect their woofers and circuitry from overload, but I could be flat-out wrong and again, please correct me if I am.

I find it interesting how wealthy many of you seem to be. It's quite a testament to Ascend products that people with $6000 subs pair them with Sierra speakers. This would clearly indicate that price was not really a factor in your chosing Ascend, only performance.

[SteveCallas]

I disagree with everything stated in the original post. If your subwoofer doesn't sound like it fits in, a simple spl meter and a free program like RoomEQ Wizard can shed a lot of light on why. There is no inherent reason a subwoofer can't blend in seamlessly, and, simply put, no bookshelf speaker like the Sierras will have anywere near the clean output capability, frequency response linearity, and extension of a good subwoofer.

Also, the whole "audiophile" thing with a signal passing through less circuitry is just a bunch of marketing. Blind listening tests will easily confirm this. I also use a Yamaha receiver that has this function, but I would never dream of bypassing my subwoofer for any type of critical listening.


Most subs are not as fast/detailed as bass emminating from a great speaker like the Sierra. Sealed designs tend to be more musical, but the Sierra's bass will still beat just about any sub in tightness and precision, hands-down.

There is no such thing as "fast" bass, and again, any decent sub will have significantly better bass performance than a bookshelf speaker. What you are probably hearing and liking is the high harmonic distortion that a bookshelf speaker will create when asked to reproduce frequencies in the bass range - those harmonics will add artificial oomph in higher frequencies that often gets described as punchy. It's fine to like that sound, everyone prefers different sonic characteristics, but technically, it's a far less accurate representation of the original signal than a subwoofer would create.

[robruffo]

Maybe we are having disagreements of semantics and situations here, but I agree that a "good" subwoofer will do what you say. However, that "good" subwoofer will cost a good bit, much, much more than the difference between Sierras and 340s - that's ALL I am saying regarding the bass potential of Sierras. Crossing over at a lower frequency (at least for music) will also help and Sierras make this possible.

I disagree with you regrading the benefits of "pure direct". A side by side comparison (even a blind one) make the difference quite obvious - on one side you have "straight" (no surround) mode with sub turned off and speakers set to large, on the other you have "pure direct". Pure direct does add something. It's very, very far from night and day but it's still audible.

[SteveCallas]

but I agree that a "good" subwoofer will do what you say. However, that "good" subwoofer will cost a good bit, much, much more than the difference between Sierras and 340s
Bought commercially, I would tend to agree. Subwoofers are one aspect of the audio chain where DIY is by and large the best option due to the performance per dollar ratio, simplicity of the build, and customization factor.