Help with subwoofer setup

[Fastnbulbous]

This is the first time I've used a powered subwoofer, and I'm a little confused.

I currently have a Yamaha HTR-5730 receiver. It has a single subwoofer RCA output jack. The manual says, "When using a subwoofer with built-in amplifier, connect the input jack of the subwoofer system to this jack. This unit will direct low bass signals distributed from the front, center and/or surround channels to this jack in accordance with your SPEAKER SET selections. The LFE (low-frequency effeect) signals generated when Dolby Digital or DTS is decoded are also directed to this jack in accordance with your speaker set selections."

You can click on the image below to get close-ups.

<a href=http://www.yamaha.com/yec/products/backs/bHTR5730.htm#><img src=http://www.yamaha.com/yec/products/prod_images/HTR5730_backM.gif></a>

In the Sunfire True Super Junior manual, it says of the line level inputs: "Connect with RCA type patch cords to teh line level outputs of your receiver or preamp. If your receiver has a single sub/LFE output, connect it to the subwoofer's left input jack. There is no need to use the subwoofer's right input jack. "

However, there's also normal speaker level inputs, with line level "high-pass" outputs (not sure what that means). "These outputs are active whenever a signal is hooked up to the inputs of the subwoofer. This crossover is a passive network with a fixed crossover frequency of 70 Hz and a 6 dB per octave slope.

We recommend using this high-pass function with main/satellite speakres that are small and not designed to reproduce low frequencies. If your main speakers are capable of operating full range, then you will not need to use the high-pass function.

To use the high-pass outputs, connect the preamp outs on your preamp/receiver to the subwoofer's line level inputs using RCA patch dcords. Then connect a second patchcord from the subwoofer's outputs to the inputs of your main amplifier. This will alow your main speakers to operate at frequencies above 70 Hz and the subwoofer to operate at frequencies below 70 Hz."

So the question is, which way should I do it? I have Rega R3 front speakers with three drivers. The biggest is only 5", so I presumed I need a subwoofer. I don't know what is considered full range. The manual doesn't specify, and my Rega manual doesn't even say what the frequency range is. Also, I'm thoroughly confused with the last paragraph. Which input jacks in the receiver do I plug the subwoofer into??

<a href=http://www.sunfire.com/SuperJrPR.htm#owner><img src=http://www.sunfire.com/images/products_2005/primary_SUPERJRSUB.jpg></a>

Thanks.

 

[MDS]

Connect a single RCA cable from the Yamaha's 'subwoofer out' jack to the left input of the True Junior sub. If you want you can use a Y adapter so you can connect to both the left and right inputs of the sub - doing so will simply boost the signal a bit. It is not necessary as the manual states, but sometimes a slightly stronger signal helps to make the 'auto-on' feature of the sub more reliable.

The speaker level inputs would be used if you wanted to connect the sub to the receiver using the front channel speaker outs. You would then connect the front speakers to the sub. They are 'high pass' outputs because the sub itself also has a crossover control. The sub's xover would be active if you used the speaker level hookup. You can use this hookup but it is not recommended because you can use the single subwoofer output of the receiver, which will enable the bass management features of the receiver.

The other option mentioned in the sub manual requires pre-outs and main-in jacks on the receiver. You would send the line level signal out the pre-outs to the sub and the sub would apply its xover and send the signal back into the receiver/amp to be amplified. No receivers nowadays have main-in jacks so this option is not a consideration.

The sub provides all those various options simply to make it compatible with a wide range of pre-amps/amps.

 

[knobturner75]

If you don't mind, I'm going to butt in here and ask a question for myself. If you had small bookshelf speakers for the fronts, would you do both, hookup the speaker level and the RCA? Because this is how I have run my ht setup for about 4 years with no probs, that I know of... I have a Jensen 5.1 speaker system (I donated the 8 inch sub to my dad) with a 10 in Velodyne CT series sub. Like I said, I have had no noticable problems to date. I have had my sub shutdown one time during a movie. It was towards the end of The Matrix Reloaded, and I had it cranked up pretty loud. I've always wondered if I was doing wrong by having it hooked up this way. I just figured it would give me the best of both worlds, a sub for my music, and the extra LFE track signal for the Dolby and DTS. Thanks for allowing me to butt in.

 

[Fastnbulbous]

Thank you sensei *bow*.

At first I thought it wasn't working. But then I switched from 2 Channel Stereo to a DPS effect, and it kicked in. It's annoying, as I don't like the echoey "concert" setting or any of the others.

Perhaps I'll try the other method of splitting the signal.

 

[MDS]

If you don't mind, I'm going to butt in here and ask a question for myself. If you had small bookshelf speakers for the fronts, would you do both, hookup the speaker level and the RCA? Because this is how I have run my ht setup for about 4 years with no probs, that I know of...

I've always wondered if I was doing wrong by having it hooked up this way. I just figured it would give me the best of both worlds, a sub for my music, and the extra LFE track signal for the Dolby and DTS. Thanks for allowing me to butt in.

It won't hurt anything but how the bass and LFE is directed depends on how the receiver is set up. You didn't mention the receiver and I assume it has bass mgmt features; ie speakers settings of Large vs Small, xover, and speaker distance settings (time alignment).

The 'normal' and preferred method is to use the subwoofer out of the receiver to the sub, with each channel set to Small, and an appropriate xover setting. With that setup, all bass below the xover is sent to the sub - including LFE (which is only present in DD/DTS tracks). If your receiver is set up that way and you also have the sub connected via speaker level inputs, you will be sending the sub a high passed signal and it will apply its xover to that signal. So...if the xover on the receiver is set to 80Hz, the sub will see 80 Hz and up only. If the sub's xover is set lower than 80 Hz (say 60 Hz), you will have a hole in the frequency response as it will further filter the signal - it will amplify 60 Hz and below and send everything from roughly 40 Hz to 80 Hz to the bookshelf speakers. You lose all the frequencies above 80 Hz for the front bookshelf speakers. If the sub's xover is set higher than the receiver's xover, it won't play anything at all.

If you set the front channels of the receiver to Large and Subwoofer=No, then the sub will get a full range signal, apply its xover and send the rest to the front bookshelf speakers. Most receivers route LFE to the Large speakers if the subwoofer is set to No/Off in the set up menu so you don't lose the LFE. But you have no subwoofer (from the receiver's point of view) so any other channels that are set to Small will have their bass below the xover sent to the front channels (because they are set to Large) which will get sent to the sub, be filtered, and the rest sent to the bookshelf speakers.
There is no signal being sent out the subwoofer out jack of the receiver so there is no reason to have a cable connected.

Pick one connection or the other. The subwoofer out is the simplest and generally best way to connect a sub - especially with small bookshelves which rarely have good bass response.

 

[knobturner75]

Thank you for letting me butt in and thank you for your response to my question. At this moment my receiver is a Sony, but as soon as the big brown truck stops at my house today, I will have a new Yamaha RX-V1600. Which means that I get to go through my system and correct my wrongs. Again, thank you very much.

NOW WHERE IS THAT BIG BROWN TRUCK!!!