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Ahhh--Problem solved. Adding a REL sub-bass unit...

I'm wondering how many audiophiles have given up on loudspeakers preamturely, or have gone down the rabbit hole of cable swapping to "fix" an issue with their speakers.  

I grew up hating subwoofers and home theatre.  I still haven't come around fully to home theatre.  I've warmed up though.  I've had my own issues with otherwise great loudspeakers, including a pair of Klipsch Forte IIIs.  I was very frustrated as I'm feeding them from a respected tube integrated, I've tried them with a 300B amp, and I've toiled over positioning.  

The issue that I was having was the mids and highs were dominating in my room--despite the size of the woofer and passive radiator. Some recordings were just too bright.  Sometimes I felt the speaker, however "alive" and dynamic was not imaging well, needed soundstage help, and so on.  

I hate to say the REL T9i I threw in the mix today is a panacea because there's always stuff to tweak.  Yet I have experienced this before with a Sumiko subwoofer.  Adding one to the mix and dialing it in so that it's barely audible has brought everything into focus.  Everything is more relaxed and energetic at the same time.  

I'd say that the REL is a room tuning device above all.  I have a larger room (I think it's 15 wide, 24 long and 10 high--in feet).   I'm not sure how much I'd have to spend or what different choices would solve this otherwise.  From a guy that used to reject subwoofers out of hand (my bias came from the 90s home theatre craze) I think that they might be necessary in the lion's share of systems with the lion's share of speakers.  To say, "you don't need a sub" with speakers might be true depending on your room, but I also think in most situations you are missing out on what they can do for so many criteria that are not necessarily in keeping with adding bass--e.g. soundstage, focus, imagine, fullness, taming treble, etc.). 

Finally, I really wish that I could try some other brands as many audiogon members recommended so many respectable names.  I ultimately went with REL because of its philosophy, my similar experience with a Sumiko sub (within the family of REL or somehow related), and the high frequency input connections. 
128x128jbhiller
ieales's avatar
ieales
1,201 posts
 
(I always enjoy hearing what engineers hear)
Almost no one ever will. The room and electronics are vastly different. Nowadays, by the time the label gets done ’improving’, any similarity between what was mixed and what’s on the disk is quite small. Doubly so for ’remasters’ See http://ielogical.com/Audio/#ReIssues

A system without the bottom octave is a pale simulacrum and loses more that ½ the immediacy of a live performance.

IMO, most systems with subs are egregiously awful. It’s often not the fault of the sub, but the set up:
1. 0-180° Phase controls are only valid at one frequency. If the phase is not correct, the system is likely better w/o the sub. Filters change the phase response making the two controls interactive. Given that small subs have large EQ curves built into their amplifiers, the phase pot marking is next to worthless in terms of absolute phase. 180° phase switches are next useless except when used in concert with a 0-180° phase control.
2. A system with powered sub should use a XOver to remove the lowest frequencies from the mains and is preferrable ot trying to ’blend’. Doing so reduces main power requirements, driver excursion and distortion. Feeding the sub first and then the sub feeding the mains is bollox. A simple single capacitor will give a 6db/octave filter which will give a nice blend with a 18db/octave sub rolloff, provided the sub phase is inverted. Getting the phase and frequency correct is tedious. It can be calculated if one knows the amp EQ, driver response, crossover type and slope. Having a close starting point is vastly preferrable to most of the ’instructions’
3. Many systems crossover an octave too low. IMO, speakers should be crossover an octave above where they start to fail badly. In the case of small monitors like LS3/5a, Spica TC-50, that’s around 100Hz. The problem is then to find a sub with similar sonic characteristics to the mains. If the mains are capable of true 30Hz, IMO there is almost no need and even less probablity that adding subs will improve the system unless the mains are placed for WAF rather than sonics.
4. Ported subs? Never!

When properly set up, pop bass is focused and does not stroll. Tympani and bass drum become focused. The sense that one is there is out all proportion to the measured delta.
See http://ielogical.com/Audio/SubTerrBlues.php for a bit of a primer on integrating a small sub and small monitors.
mtrot
804 posts
 
Yes, I'm getting close to adding a center channel speaker to my setup, but will not do so without, at the same time, also adding a REL sub with the Speakon connection. 

Years back, I tried 3 or 4 center channel speakers, but when using them, I lost all the mid and deep bass presence in the center channel, compared to when I was using my front mains as a "phantom" center channel.  I tried all sorts of crossover settings in both my sub and AVR, but could not replicate the sound of deep male voice that I got out of my front L/R speakers.  So, I stuck with using the "phantom" mode.

Last year, however, I heard a home theater setup in which they were using the REL Ti series subs to extend the frequency response of some B&W 804D3 front channel speakers.  Man, it really makes a dramatic difference to get authoritative and quality bass down to 30 Hz from the front channels. 
steakster
1,794 posts
 
2. A system with powered sub should use a XOver to remove the lowest frequencies from the mains and is preferrable ot trying to ’blend’.

If the mains are capable of true 30Hz, IMO there is almost no need and even less probablity that adding subs will improve the system unless the mains are placed for WAF rather than sonics.

4. Ported subs? Never!
Disinformation abounds here.
peterf6
72 posts
 
Thanks for all the interesting details, ieales. 
ieales's avatar
ieales
1,201 posts
 
@steakster 
Disinformation abounds here.
Prefer it if you can refute engineering facts. 

2. - Loudspeaker designers spend great effort creating crossovers for LF/Mid/HF bands. Mathematically it's almost impossible to mate a 12" driver to 8" or smaller driver in a vastly different box with no filter and get seamless integration. The level may be relatively flat, but the phase will be a nightmare. Until one has heard a minimum phase error system playing all 10 octaves, one has never heard bass correctly reproduced.

4. - Ported speakers have large amounts of time / phase shift, and the lower you go, the worse it gets.: "Bass reflex cabinets have relatively poor transient response, causing "smearing" or a longer resonance of the bass notes. Though the sound coming out of the port may have the same phase of that from the front surface, but it can never be at the same time, thus, the extended bass energy is really noise disguised as signal. The disguise works only when the sound is a continuous tone (one of the reason why some people prefer some particular kind of music for their audio system), but reveals itself most apparently at reproducing percussion sound."  https://en.wikipedia.org/wiki/Bass_reflex#Limitations 

As a great musician friend once said on hearing my system "Those little speakers aren't putting out all that gorgeous bass?!?!?!?!?" Informed of the sub, he stated "Every other subwoofer I've ever heard just boomed!!"

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