Do you think you need a subwoofer?

rauliruegas:

I thank you for this post and all of the expertise you bring. I find this fascinating and it is a ongoing part of my personal audio journey.

I've always felt that two subs are superior in reproducing appropriate sound in an audio system. The arguments you make are just spot on.

My ongoing issue now is integrating. I'm always experimenting with the controls (2) Martin Logan Depthi's). Currently, my issue is...How is the best way in which to connect?

(1) By the RCA outs from a preamp?
(2) By the speaker level inputs from an amp?

I've used for years the (1) , and find, upon thinking it through, it makes less sense. (Why not run the signal straight to your amp instead of through a whole separate circuitry?) Then the amp's character has more of a role to the subs, thus better integration. (ala = REL?)

I'm going to try (2), (next week), by using prepared cables (shotgun) that allow me to go ((after the signal comes directly from my preamp to amp)), a cable for each sub that allows each individual channel amp output to each individual subs stereo speaker level inputs, R&L per sub.

Regarding placement.. the conventional way of "in the corners", I found to be not very useful. I think this comes mostly out of "out of sight, out of mind, and a WAF". I have found that placing them close to the main speakers makes the most sense. This does interfere with most user's "other factors", as I previously stated. It does, however make the most sense in that it can integrate better with the music as it is naturally made... in stereo!

The "old school" of thought was to place them in the corners or across the room, (out of the way) since bass has been perceived as non-directional.

I've found that in looking/listening to this issue, nothing could be farther from the truth!

I could go on, but appreciate any further thoughts you may have.

Cheers,

Steve

Dear Steve, If your subwoofers have built-in amplification designed to receive signal from a line-level source, you will have a big problem driving those amplifiers from the output of your main amplifier; it won't work.  The signal voltage is much too high at the outputs of the main amplifier to drive an input designed for line level. REL specifically designs their subwoofer amplifiers to be driven by the output of a primary amplifier.  If on the other hand you are thinking of just driving the subwoofers in parallel with your main speakers, from the same single amplifier, then in part you lose one of the benefits of using a subwoofer, which is that bi-amplification removes much of the burden from the main amplifier. No free lunch.

Dear slaw: My advise through this thread that comes from my first hand experiences is that the signal from the preamp must goes directly to the subs and directly to the main amp or amps.
We want the same kind/graded of signal in both sides: subs and main speakers.

If the signal from the amp outputs goes to the subs this signal is diferent and with higher degradation.
You said : """  Then the amp's character has more of a role to the subs """, well this is not what I want it. What I want it is to have on both sides the same graded signal.

In my system I run the preamp signal directly to the subs and directly to the amps and the high-pass crossover happens inside the input circuit in my amps that are modified for that can happens. I don't use the crossover in the subs to do it or any after market crossover .

Obviously you can try what you want or what your system permits and through your listening tests  decide what  works better in your system to achieve your self music/sound priorities/targets.

Btw, which speakers do you own?

Regards and enjoy the music,
R.

I agree with the substance of Raul's advice.  In certain circumstances, one can get away with a first-order hi-pass crossover, which can therefore consist of nothing but a small value capacitor in series with the input of the amplifier that drives the main speakers, affording the least possible coloration.  Then you can add, for one example, an active lo-pass crossover to drive the woofer amplifiers, which can be much steeper in slope.

Dear friends: When we are for sure that there is nothing more to learn in any specific audio subject then suddenly we discover something else to improve the quality MUSIC/sound reproduction of our room-audio system.

I untouched my two Velodynes for years but looking for something else in my place I found out |an electrical line power regulator that I bougth so many years that I can't remember when. This same item has filters to reduce line noise and RFI/EM too, I think noise is reduced by 80-100 db.

I learned through the AHEE that it's not convenient to use that kind of power line " conditioners " with amplifiers and as a fact I never did it, I try it but in those times I can't detect improvements when in use.

Maybe I'm the only audiophile that did not do it what I explain next:

Well, I  connected both subwoofers to that device and I was totally unprepared for the HUGE and OUTSTANDING improvement in every single part of the frequency range of my whole audio system and I can tell you with all my humble " body " that the quality level I have is really excellent .

Believe me, I have no words to express it in the rigth way because for me is a totally NEW EXPERIENCE! ! !  after 40+ years to love MUSIC/sound reproduction at home.

I'm still trying to assimilate the overall improvements and I will posts on that.

In the mean time your experiences you already had are welcomed.

Regards and enjoy the music,
R.