Why no bass from sub, RSP1068 "yes" mode

[bleeding ears]

Hi again guys, I have another question that I hope someone can help me with.

Why is there not any bass from my subwoofer when the processor (1068) is set to YES mode for the sub. I get nothing even when the volume is turned up to what would usually be loud levels.

I am talking about 2 channel cd's only.

DVD's get the sub working fine in any mode.

My mains are set to large and cross to the sub at 60hz.
the sub is set to 80hz.

If I switch to the MAX setting on the processor (which is not my preferred mode) the bass can become a bit much and needs to be turned down somewhat to be not overbearing.

I do actually get pretty good bass without the sub working however I would like to have the option of adding it if I wanted.

Any idea where the bass went? or what may be happening ?

Is this a malfunction of the processor?

Pete

[Kevin D]

When the fronts are set to large, the only sound you'll get from the sub is the .1 information (either from 5.1 sources or created via a surround mode).

When set to large, the front crossover has no effect. You will need to set them to small and adjust the crossover's and level's for stereo mode to get some output.

Kevin D.

[stewfoo]

Working off of my memory from the 1068, isnt there a "max" setting that duplicates the low frequencies to both the mains and sub???
That is an extremely flexible pre/pro. The Prob with the duplicating the signal is that you get a rough transition point from mains to sub. Crossover must be done at the sub in this case..

[>>Angel<<]

Pete,


Like Kevin indicated the ony way to get a bass signal out of the subwoofer when listening to a 2 channel (analog) audio source is to put the speaker size in the 1068 to SMALL. In this way the subwoofer crossover frequency will be used. Be aware of the fact that the subwoofer crossover freq. will be overulled by the individual speakerchannel crossover freq. E.g. when the subwoofer is set to 100hz and the SMALL front speakers are set to 80hz, the latter will be leading. In case no adjustments have been made concerning the SMALL speakers, the crossover freq. of the subwoofer (in this case 100hz) will be maintained. In other words the crossover freq. of the sub is a generic setting in contrast to the individual speaker setting (which is specific).

I hope this answers your questions;-)

Angelo

[bleeding ears]

Ok guys thanks for the replies, great info.

Why would Rotel make this "no sub" with large fronts happen? (stereo only)

I must say that I probably dont need the sub for 2 channel when the fronts are set to large, however it would be nice to see how it goes.

I guess setting the processor to MAX is a way around it, but it does seem to produce excessive amounts of bass.

I have tried reducing the volume from the sub in MAX mode and blending it in with the large fronts which does seem to work most of the time however it sometimes seems to not blend well, it depends on the disc, the volume and the recording.

Having large fronts, I do want to use them so having to set them to small seems a bit silly, especially since it does not sound as good. (bit thin sounding)

Once again why would Rotel make the processor work this way???

Any ideas?

Pete

[Kevin D]

It's not Rotel, it's everyone. That's the way it works. If the source (Stereo) does not provide a sub signal, you won't get one unless you apply crossover's to the signal.

Very few speakers are full range enough to be condered large. Unless they play flat down to 30-35hz(and you have enough power to produce a controlled flat sound there), I would set them to small and adjust crossovers to your liking. The crossover's aren't brick walls, setting it to 60hz will still allow infomation from 20-60hz pass, but it will be a quieter slope down to the low end.

Kevin D.

[Elvis]

How about using the analog multi inputs for 2.1 channel listening?I redirect the sub and it works great for 2ch.

[bleeding ears]

Thanks Kev, I will do a bit of experimentation with the fronts set to small and see how it sounds.

I am now questioning my purchase of reasonable large speakers.

It appears that I could have purchased bookshelves and got the same result.

Do you think this is the case?

Elvis, what do you mean by redirecting the sub?
Does it go to the fronts and how exactly is this done?

thanks guys, Pete

[Mark_C.]

How about just running your R and L as large and leave the sub out of it. Then you're getting your money's worth. You might need some time to get used to music with unprocessed bass vs. the bang and boom of a sub when watching movies. Otherwise, your best bet is to set them as small and let the sub do the heavy lifting. You won't be wasting floorstanders that way. The cabinets of floorstanders are generally better built than bookshelves and they may offer better imaging and clarity.

[bleeding ears]

Yes, in reality the bass output with just the mains set to large is probably adequate without the sub.

I just keep looking for better. Better bass, better highs, better everything, and being unable to use the sub in YES mode with the fronts set to large had me wondering.

Getting great bass whilst keeping it tight sounding is the trick and this may be why the processor works this way I guess.

Kev, a speaker playing flat all the way to 30hz?

Im not exactly sure what that means could you explain?

The rating given for my speakers was 31hz @ -3db I think is that close?

Thanks
Pete

[grit]

Damn Pete! all the way to 31Hz? If I'm not mistaken, about -6db equates to 1/2 as loud. So, that means your speakers start to lose their lower end "umph" around maybe 36-40Hz.

Here's the solution you need: Figure out what your speakers cut-off is for bass (based on the statistics or your listening experience). Lets presume for my example, it's 40Hz. Run your front speakers as "Small". Then set the crossover at 40Hz. Thus, your full range front speakers are handling the signal all the way to 40 Hz. After that, you're taking the load off them and handing the REAL low stuff over to your sub. That should give you exactly what you're looking for.

I'm too lazy to go look: Can the Rotel 1068 have separate bass crossovers for different modes (eg, "music" gets one x-over, DD gets another).

Now, all that said, I think you'll believe somethings not working because I doubt you'll see your sub make any difference with music. I don't really believe most music has instruments playing that low.

On top of that, I think you should try flipping between "stereo" and "bypass" mode, using JUST your front speakers. Bypass mode skips ALL processing. When you use "stereo" mode (which is what allows you to send part of the signal to the subwoofer), the signal is converted from analog to digital, processed, and converted BACK to analog. This processing 'changes' the signal. Most prefer the unprocessed sound, presuming you have a good quality CD player. I purchased a dedicated CD player (Rotel 1072) because of the difference this made, rather than use my Rotel 1060 DVD player as the source.

[bleeding ears]

Grit, yes I have tried bypass mode and it is at times better than stereo, however sometimes I find I like to add treble or reduce the bass that I get and then I have to switch to stereo. (no tone adjustments in bypass).

The need to adjust the tone controls may be due to a number of factors including my setup, my room, the particular disc being played and my preference.

As far as the crossovers go, it is possible to have different sub volumes for stereo, DD,DTS,Prologic and one or two other modes, however they all share the one hz setting of your choosing.

The fronts centre and rears have their individual hz settings where they crossover to the sub, I use 60hz for the fronts.

You can also pick large, small or master for each speaker.
You can also pick from MAX, YES or No settings for the sub.

How these all interact does get a tad confusing.

I for one dont understand how the fronts could be set to small and yet have a hz setting of 40 where they cross to the sub.

I thought once you selected the small setting for the fronts they would not receive any bass below say 80 or 100 hz. Isn't this why there are speaker size choices?

After a little thought I think the best way to go is to just use the fronts without the sub for cd playing, afterall this is what 2 channel systems do and they are supposedly the way to go for cds

Pete

[Kevin D]

You can set large/small for individual modes as well. Its under advanced in the speaker setup. The large/small on the speaker determine whether to use the crossover or not, small speakers are crossed over at whatever frequency you choose. The combination of the sub crossover can be used for setting gaps or boosts in frequency. IE, if you set the sub at 40 and the fronts to 80, you will have lower output from 40-80.

It won't be 'missing' since the crossover's are slopes, not walls. If you reversed it (sub at 80, fronts at 40) you would have boosted info from 40-80. Again, it won't be 'doubled' as they are both running on slopes.

So you can try small, 40hz on the fronts. And try 40hz for the sub. If this isn't enough low output, try bumping the sub to 60hz, slightly boosting the 40-60hz range.

Kevin D.

[aud19]

Small and large could also be labeled as "crossover" and "no crossover". The size of the speaker really has very little to do with it.

FWIW, with my C9's I run them small with a 60hz crossover for movies and DPLII (music and movies) and generally listen to them "full range" with CD's/DVD-A's.

[bleeding ears]

great stuff guys, I am learning lots. All is not what I thought it was about crossovers etc.

I have gone back and tried the fronts set to small again in all the formats (DD, DTS, STEREO,PL, ETC).

The sound was a little thin at first in all modes at low volumes, just as I had found before. Then I pumped the volume up a bit changed the tone a bit and I started getting closer to what I wanted.

Some adjustments to the sub crossover and finally it seems to sound pretty good in all the modes. Just a bit less bass than I can get in large setting,but more dynamic with less loose bass sounds from sub.

I seem to get a more open sound from the fronts whilst retaining reasonably good bass. The sub seems more accurate and tighter for some reason?

Perhaps setting the fronts to small has taken some work away from them which probably gets them a bit more power as well.

In stereo I could go either way Large or small for the fronts both are good.
Large just gets that little extra bass it seems, but is perhaps not as open sounding.

I think I will be leaving all the speakers in the small setting as was suggested to me here.

I doubted that advice to start with, especially since I have large fronts but now I see, or rather hear, what you guys were telling me.

Where else could I have got this info, no where I know of.

You guys know your stuff pretty darn well.

this is why I love this forum.

thanks again guys, I am going back to listen to the new sound I get

Pete :T

[grit]

Glad you found a setting you like Pete! As Jason pointed out, calling the speakers "large" and "small" is very poor nomenclature. And you are right, setting the fronts to "small" and redirecting the low-end does take some of the work load off them, and may produce a better mid/high, esp if your amp is struggling for headroom (ie, reserve power). This theory is true of a sub. If you try to give it too much work (20-200 Hz), it'll falter. By having it produce only the lower range (usually 80Hz and down), you're taking the load off it it too. Keep playing, and let your ears be the judge. I'm so bad, I actually take a notepad with me, write down my settings, and make comments.

Oh, btw, the reason things sound lower volume after you leave bypass mode is because of the 1068. It converts the signal to digital and back to analog, and it just happens to lower it a tad (for whatever reason).

[aud19]

Glad it's working out :T