Crossover point-less?

[CraigV]

I wasn’t sure where to post this, so I hope it’s OK here.

There’s no shortage of posts dealing with when/where/how best to cross over from any of the available 5 (or more) speakers to the subwoofer, and we’re all aware of how many different configurations and sizes of speakers there are available on the HT market.
This has me wondering – in the case of surround sound mixing for movies, do the engineers take this into consideration? Do they purposely roll off the bass response going to the main, center & surround speakers, or do they let it all hang out, and let the receiver and end user decide how the bass should be handled?

The reason I ask is this; my setup (as listed below) is somewhat unique. I have the BD55 player decoding all surround modes and out-putting via analog cables (one for each channel) into the Rotel pre-pro. Because of this configuration, I am not able to use the Rotel’s built in subwoofer crossover. The BD player offers a crossover, but at a point of 100hz, I felt it was too high, so I left the speaker settings on “large”. I found out from Rotel that in this multi-channel input mode, the pre/pro “copies” all frequencies below 100hz and sends them to the subwoofer.
Soon after getting my first outboard amp set up, I wanted to hear what it could do, so I popped in my copy of The Dark Knight on BD, and turned up the volume. It didn’t take long to realize I hadn’t yet switched on the amplifier, but my subwoofers were on. I was watching the underground street chase scene, and noticed something peculiar – there was hardly any sound coming from the subwoofers. Normally, I would just take this as absence of LFE effects, but knowing the Rotel was copying everything below 100hz, I was amazed at how much sound didn’t fall into this range. Roaring engines, gun-shots, explosions, crashes, voices – not much was coming out of the subs. Once I turned on the main amp, the sound was all there, but I was surprised at how much of the sound resided above this threshold.

Does anyone have any insight into this?

 

[lsiberian]

I wasn’t sure where to post this, so I hope it’s OK here.

There’s no shortage of posts dealing with when/where/how best to cross over from any of the available 5 (or more) speakers to the subwoofer, and we’re all aware of how many different configurations and sizes of speakers there are available on the HT market.
This has me wondering – in the case of surround sound mixing for movies, do the engineers take this into consideration? Do they purposely roll off the bass response going to the main, center & surround speakers, or do they let it all hang out, and let the receiver and end user decide how the bass should be handled?

The reason I ask is this; my setup (as listed below) is somewhat unique. I have the BD55 player decoding all surround modes and out-putting via analog cables (one for each channel) into the Rotel pre-pro. Because of this configuration, I am not able to use the Rotel’s built in subwoofer crossover. The BD player offers a crossover, but at a point of 100hz, I felt it was too high, so I left the speaker settings on “large”. I found out from Rotel that in this multi-channel input mode, the pre/pro “copies” all frequencies below 100hz and sends them to the subwoofer.
Soon after getting my first outboard amp set up, I wanted to hear what it could do, so I popped in my copy of The Dark Knight on BD, and turned up the volume. It didn’t take long to realize I hadn’t yet switched on the amplifier, but my subwoofers were on. I was watching the underground street chase scene, and noticed something peculiar – there was hardly any sound coming from the subwoofers. Normally, I would just take this as absence of LFE effects, but knowing the Rotel was copying everything below 100hz, I was amazed at how much sound didn’t fall into this range. Roaring engines, gun-shots, explosions, crashes, voices – not much was coming out of the subs. Once I turned on the main amp, the sound was all there, but I was surprised at how much of the sound resided above this threshold.

Does anyone have any insight into this?

It usually helps to turn the amp on

100hz isn't that high. The difference between 80 to 100hz is fairly trivial according to what i've heard.

There are several possibilities. did you walk around the room or stand in one place? Did you feel the LFE at all? If not I suspect you have room issues or a room to large for the subs. Also you may need to raise your sub volume.

Believe me even my Dayton 10" is noticeable. So you did something wrong.

 

[CraigV]

I wasn’t sure, so I got up close to the driver to check it out - no output.

 

[CraigV]

Maybe it was just the way The Dark Knight movie was done - I just tried the same “experiment” with Transformers, and there was much more coming out of the subs. Odd.

 

[DD66000]

A lot of what we think of as bass, is really mid-bass. And that is the reason for always wanting mains/surrounds that have good mid-bass drivers/output.

 

[TLS Guy]

I wasn’t sure where to post this, so I hope it’s OK here.

There’s no shortage of posts dealing with when/where/how best to cross over from any of the available 5 (or more) speakers to the subwoofer, and we’re all aware of how many different configurations and sizes of speakers there are available on the HT market.
This has me wondering – in the case of surround sound mixing for movies, do the engineers take this into consideration? Do they purposely roll off the bass response going to the main, center & surround speakers, or do they let it all hang out, and let the receiver and end user decide how the bass should be handled?

The reason I ask is this; my setup (as listed below) is somewhat unique. I have the BD55 player decoding all surround modes and out-putting via analog cables (one for each channel) into the Rotel pre-pro. Because of this configuration, I am not able to use the Rotel’s built in subwoofer crossover. The BD player offers a crossover, but at a point of 100hz, I felt it was too high, so I left the speaker settings on “large”. I found out from Rotel that in this multi-channel input mode, the pre/pro “copies” all frequencies below 100hz and sends them to the subwoofer.
Soon after getting my first outboard amp set up, I wanted to hear what it could do, so I popped in my copy of The Dark Knight on BD, and turned up the volume. It didn’t take long to realize I hadn’t yet switched on the amplifier, but my subwoofers were on. I was watching the underground street chase scene, and noticed something peculiar – there was hardly any sound coming from the subwoofers. Normally, I would just take this as absence of LFE effects, but knowing the Rotel was copying everything below 100hz, I was amazed at how much sound didn’t fall into this range. Roaring engines, gun-shots, explosions, crashes, voices – not much was coming out of the subs. Once I turned on the main amp, the sound was all there, but I was surprised at how much of the sound resided above this threshold.

Does anyone have any insight into this?

You misunderstand how the Rotel works. The analog multi inputs are all pass through, and ONLY the volume works. You can not use the crossover. You can only get to the sub from what the player outputs on the LFE output. Any bass management has to be done by the player when using the analog multi inputs

 

[CraigV]

You misunderstand how the Rotel works. The analog multi inputs are all pass through, and ONLY the volume works. You can not use the crossover. You can only get to the sub from what the player outputs on the LFE output. Any bass management has to be done by the player when using the analog multi inputs

Maybe I didn’t explain myself well enough. I do understand what you are describing, and yes you’re right. However, I am running my front mains at the “large” or full range operation from the BD player, and since the Rotel is supposed to be copying everything below 100hz from the mains & sending it to the sub, I was surprised there wasn’t more bass energy going to the mains, and thus being “copied” to the sub.

 

[TLS Guy]

Maybe I didn’t explain myself well enough. I do understand what you are describing, and yes you’re right. However, I am running my front mains at the “large” or full range operation from the BD player, and since the Rotel is supposed to be copying everything below 100hz from the mains & sending it to the sub, I was surprised there wasn’t more bass energy going to the mains, and thus being “copied” to the sub.

Large or small makes no difference. You have zero output to your sub. The sub will only output what comes into the analog sub input. The Rotel crossover is inactive on the analog multi inputs.

 

[highfigh]

It usually helps to turn the amp on

100hz isn't that high. The difference between 80 to 100hz is fairly trivial according to what i've heard.

There are several possibilities. did you walk around the room or stand in one place? Did you feel the LFE at all? If not I suspect you have room issues or a room to large for the subs. Also you may need to raise your sub volume.

Believe me even my Dayton 10" is noticeable. So you did something wrong.

The difference between 80Hz and 100Hz isn't trivial, but it's not as much of a difference as when the crossover point is changed from 40 to 80Hz. 80Hz to 100Hz ranges from E to G on the musical scale (within a few HZ on each end). Changing from 40Hz to 80Hz is a whole octave and will make a much more noticeable difference if the system has problems in this range.

 

[lsiberian]

Maybe it was just the way The Dark Knight movie was done - I just tried the same “experiment” with Transformers, and there was much more coming out of the subs. Odd.

You may have some issues that need to figured out.

Maybe you could actually buy a crossover and place in between the rotel and the player.

A Behringer CX 2310 is capable of that and goes for around 60.

 

[CraigV]

As I was understanding what the person from Rotel told me, the sound coming from the subs was a mixture of LFE effects & everything from 100hz and lower that was being copied from the main speakers running at full range. Just to be sure, I went into the setup of the BD player, and set it up as having no subwoofer in the system. Then I tried switching off the amp to see what would come out of the subs (thinking if everything below 100hz was being copied & sent out to the sub, I should hear something) and I got - nothing.
So now I’m left wondering why I was given that info.

 

[TLS Guy]

As I was understanding what the person from Rotel told me, the sound coming from the subs was a mixture of LFE effects & everything from 100hz and lower that was being copied from the main speakers running at full range. Just to be sure, I went into the setup of the BD player, and set it up as having no subwoofer in the system. Then I tried switching off the amp to see what would come out of the subs (thinking if everything below 100hz was being copied & sent out to the sub, I should hear something) and I got - nothing.
So now I’m left wondering why I was given that info.

Never get your info from idiots who work for manufacturers, agents, big box stores and a lot of dealers. Download manuals and verify everything for yourself. Take a leaf out of Adam's book and you won't go wrong.