Adding some bass?

[Gibbo]

please ignore me

[htrd]

You should be able to connect any sub with a high level (speaker level)
input to your amp. Effectively the output of your main amp is the input to
the amp in the sub.

Ive been using a http://www.bkelec.com/HiFi/Sub_Woofers/XLS200.htm in a
similar set up for 9 months now and am very pleased. On slimserver we are
lucky to be able to use the Inguz EQ plugin to correct for room effects.
Will you be able to run this? Being able to use some form of EQ to correct
for room effects is essential to get the best out of any sub.

[iPhone]

If one were looking for extended low accurate bass that seamlessly mates to main speakers for music listening (not Home Theater), a possible suggestion would be any active sub that operates by becoming active before the output to the mains. These subs have a huge advantage over LFE, passive, or add-on subs.

The first and main advantage is they completely remove the low base load from your main amplifier letting it concentrate on the highs, midrange, and upper base. They blend seamlessly into the system and sound like they are part of the mains. Volume is no longer an issue because they behave as the mains do because they are receiving the same signal sample as the mains just only the low end. It is basically like somebody added a lower base driver inside your main speakers. Thiel and Vandersteen 2Wq (the V2W is for HT LFE) active Sub-woofers are both good examples. The ability to change the Q should be a function of the subwoofer itself, not an item that affects the whole system. Why mess with the source signal when the device that needs to be adjusted can be tailored to the room?

Now for the downside, although these active subs work wonderfully with full range speakers, they were not designed to add base to satellites and most monitors. The reason is because satellites and most monitors do not have enough bass extension to reach the area most subs operate in. This issue causes a hole or at a minimum a deep valley in the bass performance between where the monitors run out of gas and the sub takes over. Which is why a sub will not fix the lack of bass authority in satellites or most monitors. Speakers used with active subs need to have reasonable response an octave below the crossover point to have realistic blending (filter theory 101). Having a sub with a high upper bass reach adds to the problem because the sub is now not operating in its bandpass and will be to weak (probably 6dB) and muddy. The primary problem being that the more bass extension the mains lack the wider (hence higher up in bass frequency) the required octave overlap becomes (one octave at 50Hz {25Hz down and 100Hz up} is a much smaller range then one octave at 200Hz {100Hz dn and 400Hz up}). As an example if one targets the crossover frequency at 50Hz, ones mains need to realistically go below 25Hz. 80Hz is my preferred cross-over point with active subwoofers. I have a choice of many full range speakers that start running out of bass gas below 40Hz and the sub never has any work load above 150Hz staying well away from the 200Hz mud zone and yields actual bass response down below 20Hz.

[Gibbo]

Cheers for the responses.

pretend I know nothing, as to be honest when it comes to this I don't really,

an active sub should have a speaker level in, that can connect to a speaker cable from the standard amp left and right outputs? how does this connect with the speakers that are also connected? series? parallel?

thanks again.

[pfarrell]

Gibbo wrote:
> an active sub should have a speaker level in, that can connect to a
> speaker cable from the standard amp left and right outputs? how does
> this connect with the speakers that are also connected? series?
> parallel?

Depends on the specifics of the sub. On my REL stadium, the speaker
level inputs are actually high impedance, so while the operate in
parallel, they really don't load down the amp.

Other subs take the speaker level input and filter it, and send a high
pass signal to the speakers. So they are essentially in series.



--
Pat Farrell
http://www.pfarrell.com/

[Gibbo]

Ok, so thing is I want to make my system a little more enjoyable for films, it doesn't really have that rumble that you sometimes need, I have kef Q3's and a C320bee NAD amp. What can I do? and in very simple terms, what would you plug and where? just want people opinions really, I know this is audiophile country, but i'm thinking cheap options, < £100.

is it possible?

[htrd]

Gibbo wrote:

> but i'm thinking cheap options, £100.
>
> is it possible?

At that price, hmm, you could pay someone to slam your front door in time to
the music.

Or, to stretch the budget a little:
http://www.avforums.com/forums/showthread.php?t=645977


I hope that helps

[zanash]

paradigm made a small sub £100 sub .....I have one I used while my floorstanders were breaking in as they produced no bass !.... but I've never been convinced that this works very well in all the systems I've heard subs used.

[Gibbo]

Cheers. really just trying to get an idea of what price would give me something of a comparable quality to the setup I have already.

[Skunk]

an active sub should have a speaker level in, that can connect to a speaker cable from the standard amp left and right outputs? how does this connect with the speakers that are also connected? series? parallel?

You can use the 'Tape Out' RCA connectors on the NAD to feed the sub a line level signal instead of speaker level, so long as the sub has left and right RCA inputs (not just a single LFE input which is meant to be feed by home theater receivers).

I would also look for a sub with a crossover frequency control in addition to volume control, which will help you blend the sound with your main speakers.