Basic Sub Question

[Unregistered]

Hi Audioholics,

I just purchased a REL Q150 Sub, which is great. I am running separates, and just have a quesiton about the input i should use. Is it better to use high input or low input connection...or both. The manual says high is always prefered. Sorry to bother u with such a basic question. Oh another thing....does the high level connection from the speaker terminals deprive the speakers of power. Thanks so much. You guys are the best.

Will

 

[Unregistered]

If you use the high level inputs ('speaker level') then you will be using the sub's crossover. If you use the low level input, you will be using the receiver's crossover and bass management capabilities.

High-level inputs should really only be preferred when the receiver has a fixed crossover because you will have more flexibility for setting a crossover frequency by using the sub's crossover.

 

[Rÿche 1]

I suggest you try both ways, and see which sounds better.

 

[Yamahaluver]

They both have their pros and cons, the high level can have a cascading effect whereas the low input is limited to a fixed frequency unless you have a receiver like the Yamaha Z-9 with variable one and in that case it is much better to use low level.

 

[cam]

If you use high level then you will be losing your .1 in 5.1. Not a total problem, just make sure in your menu, when it asks if you have a sub, put no that way your bass will then be directed to your mains which will then be filtered out to your sub via your speaker wires. A better way is always to use your low level and use your bass management in your receiver. Dial your subs crossover to its highest point that way it does not interfere with your receivers crossover point.

 

[Tons of Fun]

If it is any further help, I think REL are in minority of one in favouring the high level input (for HT work). Whilst it has merits for Stereo I would always let the receiver crack on with the bass management.

 

[Rÿche 1]

Again, I would say try both ways, and see which sounds best. I don't think it's fair to simply say that it's "better" to use low-level. Is it more convienient to use low-level? Yes. One cable to run to the sub, as opposed to the speaker wires for high-level. I will say, I hooked up the high-level with my Yamaha receiver I use to have, and I swear it sounded better. I think I would be inclined to say this... If you listen to music more than watch movies, use high-level. More movies than music? Use low-level. In the end, use your ears to judge... It's your system, not ours.

 

[mdrew]

What about noise to the speakers if running high inputs? I've been told that depending on the receiver, there may be detectable noise from the speakers due to the sygnal being amplified twice.

 

[Rÿche 1]

What about noise to the speakers if running high inputs? I've been told that depending on the receiver, there may be detectable noise from the speakers due to the sygnal being amplified twice.

I didn't notice any "Noise". Hook it up and listen to it.

 

[Yamahaluver]

Before the advent of HT receivers on the market with built in fixed and variable crossovers, the only way to attach a sub was through the high level inputs, only those who were fanatics would go for external crossovers at a high cost. The advantages of using the high level are there if you take a closer look. What happens is that by taking away the low frequencies from your main speakers and amps, you are giving them a huge break. The most power robbing facet for an amp is low bass and it is also the one which causes most dispersion in drivers. Most drivers today are 2 way with the mid/bass combined in one unit. The 3 ways are rare and fast disappearing. If low bass is taken out of the main speakers, the mid clears up due to less cone movement. This can lead to clearer sound. You can also do that by using the low level connection from your receiver to your sub and set your main speakers to SMALL but in this case, if you have good bass capable mains, it is a waste as the mains would be able to handle up to 50Hz with ease, this is where the high level input connection comes really handy by letting you do the variation to your taste and capability of the current amp/speakers.


The noise factor could be coming from the speaker cables picking up stray fields nearby from sources like transformers etc.
On another note, at least with Yamaha HT receivers(there may be others), by setting the bass out to BOTH and selecting the main speakers to LARGE, one never looses the .1 even when high level inputs are used.

 

[Unregistered]

Using the high-level inputs on your subwoofer will NOT relieve the amp of the burden of amplifying the low frequencies. The amp will have to amplify the entire frequency range and send it to the sub. The sub will then convert the high level to low level, low pass it (remove the high frequencies), and then amplify the bass frequencies.

It is only a waste to set large speakers to 'small' and use the receiver's crossover if it only has a high fixed crossover. If the receiver does have a range of crossover frequencies that are near the low point of the tower speakers it is preferable to use it over the high level inputs. That way you do eliminate the task of amplifying the low bass.