Do you think you need a subwoofer?

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.

Dear friends: First thing I can tell is that that old " warning " against line regulators with amps ( at least in my case ) is totally untrue, there is no single power limitations I can detect about.

I did it my usual whole tests wide/deep process with outstanding results.

Througth that process between other test LP tracks exist two extremely demanding bass range recordings: Telar 1812 and the RR Dafos. Both demanding not only for the speakers system or amps but everywhere from the cartridge to the room where is the audio system.

I really pushed my system with the track: Gates of Dafo's and obviously with the cannon shots in the Telarc 1812 looking for any single sign of power limitations, clipping or quality degradation at very high SPLs: 98 db at seat position with peaks over 107 dbs. It never " collapsed " in any way, everything in focus with extreme detail and resolution.

So, in my case that " warning " is a myth. Rigth now I'm waiting for other two 2.8 watts regulators to connect my monoblocks there. I have to say that I don't know what could happen when test it because my amps are fully regulated input to output. We will see.

Now and returning to the new Velodyne experiences, what am I listening through?:

- first and listening at my normal SPL this SPL " goes down ", in reality does not gone down but this is exactly what my ears and body " feels ". I know that SPL did not gone lower because I measured.

- for my " whole body " can again to feel the same SPLs than before I need to increment around 3 dbs the attenuator/volume in the Phonolinepreamp. However and after the time I just return to the past attenuator position, I don't need to do nothing about but stay there.

- in the whole bass range disappears its false bloom reproduction, false bass power feelings that is not in the recordings, notes has a never experienced clarity/resolution that today I can say are more " transparent " and with an outstanding separation in between. Yes, I'm discovering each single of my LPs ( and I say that not as the normal " cliché " some audiophiles or reviewers tell us. It's literally. ), it does not matters which one or kind of music.

- when I was feeling that I losted that " bass power "/bloom and the like what I did it was to increment the volume in the Velodynes and even that at the begining I thougth was rigth latter on I decided that was not and that I don't need to adjust the subwoofers volume but to stay as in the past.

- all those clarity, transparency and very high resolution in the bass range frequency mmade and makes that the other frequency extreme really shines as never before and yes discovering " new sounds " in the very well know recordings I have and that ow I know I really did not know so well as I imagine.

- now that both frequency extremes are THERE the mid range is too better than ever and this fact ( at least for me. ) confirm what I  was and am telling from many years now: that music at home does not belongs at the midrange frequency range but at both frequency extreme ranges that are the music frame in home reproduction.

As better both frequency extremes as better not only the mid range quality level but the overall listening experiences. Mid range depends on those frequency ranges where these frequency ranges does not depends on the mid-range.

- one part of the 1812 whole track is when we can listen the Carrillon that with its multiple bells diferent tones/harmonics and all at the same time is just imposible to identify each single of that Carrillon sounds.
Well, that was till now because I'm hearing from the very first time the real glorious of that Carrillon sounds that I never did it in any single audio system I experienced trhough my audio life ! ! !, incredible experience for say the least.



Even that some people make jokes or laugh of me ( some of you that are reading this post. ) I touted and tout, posted and post ( elsewhere ) for several years that quality level differences between different home audio systems belongs to each audio system/room DISTORTIONS LEVELS  and nothing more.

In the last times my quest was and is to make any system single change with the main target to achieve lower distortion levels and this time  ( fortunatelly. ) that " move " was and is rith on: LOWERING DISTORTION LEVELS and this fact means MORE MUSIC enjoyment.

Rigth now with that simple " move " I'm listening less to the system room/venue and more into the RECORDING. Additional what is happening/listening ( till today ) confirm not only the other changes I di it in my system in other years but what I posted in diferent audio subjects here and in other forums.

Btw, other " myth " that falls ( for me. ) is that theory that odd harmonics are so irritating to our ears and this is ( for me ) totally untrue because third or fifth bass range harmonics are pleaseant ones like the second ones and today more clear than ever and MUSIC is " harmonics ". Problem, as always, are those system distortion levels.


Yes, all pasive systems needs a pair of active subwoofers wired in true stereo fashion.

Regards and enjoy the music,
R.