Large vs. small speaker playback in HT

[subynube]

I am ready to purchase a new pre/pro as well as amp. Looking at the emotiva set up LMC-1 and LPA-1 processor and amp. I was reading the instruction download, and it says that when the front speakers are set to "large", meaning they are capable of putting out below 60hz information, then the sub output is shut off. The sub output is only on when the speakers are set to "small". I dont think I like this feature :M , in that I would like the sub on as well as speakers set to large while the front speakers play the full spectrum of bass.
So I am wondering if this is common of other processors like Rotel and such? Thanks for the advice!

[nicky]

In almost every HT receivers/processors I have owned or tried, when the speakers are set to large, the receiver or processor after decoding sends the full range including bass to those speakers set to large for that channel. BUT the decoded .1 or LFE in movies still goes to the subwoofer output....so the subwoofer output is still functional....and it should be so the subwoofer can handle the .1 in movies.....although the .1 or LFE channel from movies is not always meant for subwoofer output and can be handled by the other speakers.

When the speakers are set to small, the set bass freq are all bypassed and sent to the subwoofer output including the .1 channel from movies.

So to answer your question, in my experience, this is not common.

However, in stereo 2 channel, it is common for receivers, etc to shut down the subwoofer output when set to large for accurate stereo reproduction without subwwoofer. But not so for HT decoding, since the .1 in movies might be meant for subwoofer output.

[Ovation]

It may not be common, but it is not actually a bad feature. It avoids "double bass" distortion that frequently results when one sends a full range signal to the mains and leave the sub on. The distortion potential rises the lower your mains can go. The resulting sound is often one of "bloated bass".

Ideally, you want as steep a crossover slope as possible, to minimize bass overlap, and you want to set the crossover signal no higher than 80hz. You can use a lower crossover frequency, depending on your mains, but, on paper and in every setup I've tried, you should seek to avoid "LARGE + SUB" combinations.

If you have FIVE full range speakers and a sub, then the processor, if it is working correctly, should send ONLY the LFE channel info to the sub when "LARGE + SUB" is enabled. However, many receivers will permit a setting where the sub will receive overlapping bass that is also sent to the mains--that is NOT a desirable outcome.

Also, contrary to popular opinion, setting a crossover frequency and selecting "SMALL" for speakers (even floorstanders) is NOT a waste of the speakers. It is exceedingly rare that the best position for imaging for speakers is the same (or even close to) the position for best bass response in a room. Having a sub (or two) allows proper placement for both bass and for imaging by decoupling the functions. The speakers (and amplifiers) strain less as part of the workload is taken up by the sub. I use my sub in all situations (2 channel and MCH) for music and movies. But it did take time for me to find the best placement for the sub (and I also use bass traps and a digital PEQ for the sub). However, my bass is now clean, tight and never "bloated" and I doubt I will ever have a serious system (2 channel or MCH) without a sub in the equation.

[subynube]

Thanks for the replies folks. I still may want the option to have the speakers set to large and the sub output on as well, and it seems it is not an option in this set up. Ovation, I didnt realize how important it was not to overlap bass with sub and mains. The only problem is that I dont want my MTM (Nat. P) mains to just be putting out 60 hz and up, as I feel that would make the speakers sound too bright/forward without enough bass coming from them. Either way, I will look into it more. Thanks for the replies :T

[subynube]

This quote is taken directly from the Emotiva download:

"Please note that if you select LARGE for the main speakers, no information will be directed to the subwoofer from the “SW” output of LMC-1 on all Analog or PCM 2-channel source processing because the crossover is defeated in that setting (in other words there is no “low pass” information going to the SW output). Any discrete digital information with a dedicated LFE channel will still direct the “.1” information into the sub as normal. If you desire a separate subwoofer when using LARGE main speakers, Emotiva recommends using Y-adapters split from the main L and R channel outputs feeding both the amplifier for main speakers and a powered sub that utilizes an internal crossover"

My questions:
1. Is analog or PCM 2 channel listening just when 2 channel music is playing, not movie watching?

2. Can the LFE discrete digital information be used during 2 channel playback with music listening, or just used with Movie/home theater listening?

Thanks again folks. :T

[nicky]

When watching movies (ie multichannel), good receivers/processors do not allow "double bass" to occur.

When a speaker is set to large, the decoder will send the full freq range to that channel and will not sent that channels bass freq to the subwoofer as well....ie double bass. Only those speakers set to small, will the decoder send the set bass freq for that channel to the subwoofer. So you will not or should not get "double bass" in HT use.

Where you can get "double bass" or unnatural bass reproduction is when you are playing stereo ie 2 channel music/sound or non-multichannel encodings. True stereo is just that...2 channels not 2.1 where the .1 is the subwoofer. In receivers it is often set so the bass freq is sent to the subwoofer (ie 2.1) and you can get exaggerated bass sound. Or when the receiver tries to replicate a stereo or non-multichannel encoding to play in multichannel speakers. That is when you can get bass from all speakers and can sound unnatural. So if you want to include a subwoofer to stereo music as well, it is important to setup your receiver well so that it blends nicely and naturally to your main speakers.

From your Emotiva quote, to ensure this problem doesn't occcur, the subwoofer does not output when playing stereo....so they will only output as pure 2 channel stereo. So the receiver does not artificially separate the low freq from the stereo enoding so it will output to subwoofer, but just serve as an amp for again pure stereo sound. But it seems that the subwoofer is active when playing multichannel source like movies (ie 5.1, etc) as it should be since movies/dvds almost always use the subwoofer for their .1/LFE channel from the multichannel encodings.

The quote also says you can still use the .1 in stereo if you want to by using an adapter. What the adapter does is it separates the stereo output into two full range outputs where one set goes to the speakers for full range and the other goes to the subwoofer crossover...where the subwoofer crossover will only output the low bass freq set on the subwoofer.....but again if you do this it is important to setup the subwoofer carefully so it blends nicely with the main speakers without the bass exaggeration since the main speakers still gets the full range freq.

[subynube]

Thanks Nicky, very helpful. For some reason, some processors allow for "double bass", where the sub can be on when speakers are set to "large", and some dont. Either way, very helpful info.

[nicky]

In multichannel encodings (ie HT) the subwoofer is on even when the speakers are set to large so that it can handle and output the special LFE from the multichannel encodings. Even when the speakers are set large, movies/DVDs have separate LFE channels which are meant and are output to subwoofer....this is not "double bass" as the LFE is separate and meant for subwoofer only....that is why the subwoofer is on and should always be in HT.
When the speakers are set to small, all the low freg from the other speaker channels as well as the LFE are output to the subwoofer.

[Ovation]

He's right about some receivers, though (and even a few MCH audio players). You can deliberately select a setting (listed under a variety of names) that will create the "double bass" phenomenon.

My receiver has a "Pure Audio" setting (no video circuitry is active, not even the front panel) and it does NO processing of any kind. Essentially, my receiver becomes a passive integrated amp. In that situation, the sub is not active. "Direct" mode is essentially the same thing, but without turning off the front panel display (I've not discerned any audible difference between the two settings, but I usually use "Pure Direct" because it's the first button in line on the remote--I keep my sub active because my player can be configured internally as a 2.1 set up).

If I engage the STEREO mode, then the settings that apply when using DD or DTS are utilized (same crossover frequency/slope/level setting for sub and mains). If I engage STEREO and send the signal via a digital connection from the player, then it simply processes the signal in the digital domain. If I send an analogue signal to the receiver in STEREO mode, it does an A/D conversion, processes the signal and then does the D/A conversion. I'd have to try it, but I believe if I set the mains to LARGE, and leave the sub ON, then it will create the "double bass" issue with anything other than a DD or DTS signal.

In the end, after all my experimentation, I still think the best way to go is to set the speakers to SMALL, select an appropriate crossover that works well with the mains, and keep the sub active at all times. This will give the best bass response and allow optimal speaker placement for imaging. I would only opt for the LARGE setting if the mains were true full range speakers (exceedingly rare, especially at reasonable prices for the average person) AND I could find the "sweet spot" for speaker placement that successfully incorporates good bass response with good imaging. I suspect it would entail A LOT of trial and error placement attempts along with a significant amount of acoustic treatment of the room.

There are many excellent, reasonably priced floorstanders that can handle a good amount of bass (Paradigm Reference 100s come to mind as an example I've heard) and I could probably be very happy to have a 2 channel setup with them without a sub but if I wanted that last ounce of excellent imaging and excellent bass response, I'd likely add a sub to the mix even with those speakers. Of course, I would also be looking for appropriate gear to allow a good integration of the sub with the mains (the paucity of such gear intended for the 2 channel market is, I suspect, a serious barrier to the integration of a sub in many 2 channel systems as connecting via speaker wires is not optimal). In such a case, either an RR2150 from Outlaw (a 2 channel receiver with a built in 2.1 setup option) OR a multichannel player that can be configured for 2.1 playback (like my Cambridge Audio 540D or my Marantz DV6400) where the sub output can be directly connected to the sub if the 2 channel (integrated amp/separates/receiver) system does not have a configuration like the Outlaw RR2150 (and I know of no other 2 channel rig that offers such an option) OR an AVR (either alone or with an outboard 2 channel amp) will be needed.

In a "living room" system that is meant to be there to provide some background music, 2 channel is fine without a sub. But to me, a critical listening set up would require the sub for that final touch.

[whoaru99]

When watching movies (ie multichannel), good receivers/processors do not allow "double bass" to occur.

I disagree. "Good" receivers/processors let you choose your poison.

[bmowis]

I disagree. "Good" receivers/processors let you choose your poison.

An unqualified "Good" and "Bad" might not be the right way to look at this.

A "Good" entry-level receiver will steer an inexperienced user into making the right(tm) decision. I have a HK AVR-240 receiver at home that drops subwoofer output altogether in Stereo mode if I have my speaker size set to 'large'. It's an entry level receiver, but I have no question about it's quality.

A "Good" high-end receiver (or professional gear) assumes some familiarity and thus should allow the user to 'choose his poison'.

So instead of being a question of quality, it becomes a question of audience. Who was the receiver built for? Newbies or professionals?

Cheers,

Brad

[nicky]

I don't know how this became an issue of good or bad receivers because that was not what this was about.

All receivers basically do the same thing when handling multichannel decodings from multichannels sources like 5.1, etc. from movies in HT use. When the speakers are set to large, only the LFE meant for subwoofer encoded in movies goes to subwoofer output. If speakers are set to small, the low freq set by you on the receiver as well as the LFE meant for the subwoofer all goes to the subwoofer because by setting the speakers to small, the receiver assumes your other speaker channels can not handle the low freq that was meant for that channel only. The only other option the receiver gives for multichannel is the level of bass you want so you can increase or decrease the level of bass just like volume. So the issue with the poster was his worry of "double bass" which can not happen in a good proper functioning receiver since the low freq either goes to the intended channel (speaker set to large) or bypassed to be handled all by the subwoofer along with the subwoofers LFE duties (speakers set to small)....but not sent to both.


The only options that most receivers give while others do not is when you are playing stereo (ie 2 channel) or other non-multichannel encodings. For example, stereo is 2 channel and does not have LFE meant for subwooofer as in HT/multichannel enodings but some receivers allow subwoofer output anyway or don;t give options like pure direct modes where stereo is pure stereo and subwoofer is turned off. In cases where the subwoofer is turned on always, the stereo encoding is processed and the low freq set on the receiver is artifically outputted to the subwoofer. But some purest companies or for any other reason don't allow this option because it does not or may not sound good or if you set it wrong can sound artifical or have artifical exaggerated bass.

So this is not about good or bad receivers. Some great reputable brands choose not to output bass in stereo because they are purest while others great companies do give that option. And inversely, plenty of bad companies give poeple the options while others do not. That's NOT what makes a receivers good or bad...it's just preference that some companoes may/may not give. But again, that's not what makes a receiver good or bad.

[subynube]

Well, I took the plunge and went with the emotiva duo (processor and amp seperates). I agree that I would like to "chose my own poison" and would prefer to be able to modify the parameters myself. However, this unit is as user friendly and "plug and play" as you can get. No buttons. Just 2 knobs that control all the functions on the pre/pro. This feature is not better or worse than anything. There certainly is a market for simple processors that do all the functioning for you. Either way, hopefully it turns out well., Thanks for all the input :T

[Ovation]

Congrats and enjoy.

[whoaru99]

Good or bad in the context of the receiver/processor has the features you want/need, or it doesn't. That's all I was saying.