Active subwoofer and integrated amplifiers

[boogiewoogie]

Hey,

I'm looking to upgrade my decades old stereo amp to an Audiolab 6000A. In an article on some website, the following is stated:

I will suggest connecting an active subwoofer via Audiolab 6000A pre-out in ‘Integrated’ mode. The subwoofer will help lift the weight of producing bass off Audiolab 6000A which also helps to prevent the amp from underpowering your speakers.

Could someone help me understand, in reasonable detail if possible, how an active subwoofer connected to a pre-out can help lift any weight off of an integrated amplifier?

Also, what would the connection setup look like. Can one even make use of the crossover functionality with an active subwoofer and an integrated amp? Since if I'm not totally off base here, the other speakers would still have to be connected directly to the amp, and for crossover to work they'd have to be connected to the sub. Right?

Cheers,
Boogie

 

[AudiOhm]

First we need to understand what amp/sub woofer setup you currently have and how they are connected.

An active sub has its own built in amp and will have a crossover to limit the high/low frequencies sent to the driver.

Some subs have speaker connections that are then passed to the other speakers via speaker cables.

The Audiolab 6000A suggests that you use the pre-amp outs to feed the sub, and the speaker outs to feed the speakers.

I believe that this is the setup that most use, at least me anyways...

Ohms

 

[kemmler3D]

how an active subwoofer connected to a pre-out can help lift any weight off of an integrated amplifier?

It all works as described if you have EQ in the system even when the speakers are connected directly to the amp. If not, you're just adding a sub to whatever the integrated amp is already doing.

If you do have EQ in the system, then you add the sub to the other speakers, presumably this leaves you with too much bass energy. You then level out the response with EQ, (lower the bass) which proportionally lowers the wattage that the IA needs to output in the bass region. So in that way, the sub can take the load off the amp pretty well.

If you aren't planning to use EQ, well, you should!

 

[boogiewoogie]

If not, you're just adding a sub to whatever the integrated amp is already doing.

This is exactly what I thought and what confused me about that statement. Thanks for confirming!

If you do have EQ in the system, then you add the sub to the other speakers, presumably this leaves you with too much bass energy. You then level out the response with EQ, (lower the bass) which proportionally lowers the wattage that the IA needs to output in the bass region. So in that way, the sub can take the load off the amp pretty well.

If you aren't planning to use EQ, well, you should!

Alright, makes sense to me.

How would I "use EQ"? Is this an extra device I'd have to add in the chain? (If so, could you point me to an example of such a device?) Right now, I'm picturing turning bass/treble knobs on an amp. Which the Audiolab doesn't seem to have.


Current setup is:
PC > JDS Atom DAC > Technics SU-V50 (80's stereo amp) > 4x Eltax dx 50 (bookshelf speakers)

Which I'm looking to change to:
PC/Phone (BT) > Audiolab 6000A > 2x B&W 606 (+ SVS PB1000?)


Does that look sensible at all? Music quality would have strict priority.

Cheers,
Boogie

 

[kemmler3D]

You can run EQ on the PC, look into EQAPO, there's also a similar one for Mac. It does system-wide EQ.

Basically, the standard advice everyone gets here is to use a UMIK-1, REW and EQAPO or a similar app to EQ their sound in-room, especially for bass. There are lot of instructions on this site on how to do it. But basically what happens is you measure your in-room response and then use EQAPO to manually or semi-automatically adjust the sound.

What this looks like in practice is mostly lowering peaks in the bass region and getting it to even out with the rest of the sound. So, by doing so, you lower the demands on both the amp and subs, and end up with cleaner, smoother bass overall.