Paul’s finally lost it

August 30, 2022
 by Paul McGowan

We could all see it coming. A screw loose here, a rattle in the old brain cage, a distant look in my eyes.

Yup. Lost it.

When Octave Record’s executive producer, Jessica Carson, and I were plotting out some new releases one of the ones I was most excited about will be the first in a new series called The Art of HiFi.

The first release will be all about bass. And oh my, this is a must have for anyone that likes bass. Like me.

Once decided I knew it was time to add subwoofers in the Octave mixroom. There is some seriously low frequency material recorded at DSD256 and I don’t want to miss one Hertz of it.

The FR30s we use for monitors have amazing bass extending into the mid-20Hz region but, for those of you that know me, that’s just not the proverbial DC to light I am looking for.

To properly mix this new release I need subs that are not worried about the room and loaf along producing subsonic with ease. And, they have to be sonically invisible.

A tall order.

After hearing Darren Myer’s dual nearfield 18″ sealed woofers I was smitten. I went to our guru, Chris Brunhaver, and asked what he would recommend.

The look on Chris’ face was confusing. It was either one of pure evil or glee. I couldn’t tell which.

Chris insisted I go all out. Dual 21″ low distortion pro subs housed in slender cabinets that are nearly my height—each cabinet weighing in at 150 pounds without the woofer (and the woofer’s just about 80 pounds itself).

These beasts will sit directly across from the mix table where I sit, one pointed right at each ear.

Nearfield subwoofers are not bothered by the room. Once tuned via DSP and powered by a 1,200 watt amplifier, these bad boys will sonically disappear, and it will appear as if the FR30s just got an extra octave of lower bass response well below the limits of human hearing but not the limits of human feeling—gut thumping.

Yup, I’ve lost it.

I couldn’t be more excited. I made a short little video showing the cabinets just before we finished them.

You can watch it here.

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40 comments on “Paul’s finally lost it”

  1. What is the step-up from “full-range” (FR-30), Paul? Doesn’t this post tell that the best loudspeaker solution for “normal” listening rooms (sized as a recording and mixing room at Octave Records) sees two powerful near-field subwoofers and two small satellite speakers ranging from some 60 Hz to 20 kHz?

  2. My first thought looking at the picture was that these were a prototype PS Audio washing machine, which is exactly what people on the YouTube video thought as well.

    These do not fit in with my concept of home audio. For me very deep bass is more a test signal than anything to do with music. A very popular test track for deep bass that is actually proper music is Flight of the Cosmic Hippo, the title track from Bela Fleck’s No. 1 album. Apparently the bass guitar was tuned down to 30Hz. My speakers go to 32Hz, but I use Devialet’s SAM active bass correction DSP and the result is very acceptable.

    1. Indeed, except of organ and synthesizer music and heavy metal or action movies with a lot of explosions I rarely know music requiring full-range loudspeakers. However there are some audiophiles who claim that huge concert halls have low eigen-frequencies and they want to hear those subtle low frequencies captured by the recording microphones. And there is another huge problem with full-range speakers: listening audible and unwanted room modes already below 100 Hz. Devialet’s Phantom loudspeakers go down to 16 Hz! Thus how do you tame these room modes?

      1. Most people do nothing because the brain does more room correction than anything else.

        I’ve never had bass peaks, only cancellation, in the commonly experienced range of about 70-90Hz. This is easy to fill in with a subwoofer, if you are bothered and it is domestically suitable.

        Paul’s latest mishegas is monitoring and recording bass that most people’s systems cannot play back and even if you can, tends to be the preserve of people who live alone in remote houses or have concrete-lined basement man-caves. I had a REL S/2, really a baby sub, but it shook my not small house, even at low volumes.

        That said, and as you suggested, with mini Raidho speakers that barely went down to 80Hz, it sounded excellent.

        The Devialet Phantom have extremely deep bass and very long throw as one of the jobs they were designed to do was to be a P.A. speaker for up-market retail. They do the very well. They are great for parties. Of course they use a piston driver, much more efficient and effective than a cone. The 10″ PMC professional piston drivers do 20Hz-20kHz with zero distortion and go to 132dB. Their consumer speaker only needs a 6.5″piston driver to do 23Hz-23kHz with zero distortion, but they’re not cheap.

        Another big issue is cabinet resonance. The normal solution is high mass, but the PMC Fenestria were very innovative in using external panels as tuned mass dampers, widely used in construction for eliminating resonant frequencies. All Londoners and many visitors know about our “wobbly bridge” (the Millennium Bridge), which was closed the day after it opened because they miscalculated the footfall resonance. Tuned dampers fixed it, but it took 2 years.

        1. Some 25 years ago I terribly failed to „enrich“ the sound of my B&W CDM-1 stand-mount loudspeakers with a Bob Carver‘s active subwoofer „Sunfire“. This tiny sub was that „powerful“ it had to be fixed to the floor for hindering the box from wandering around. 🙂 At those days I had no clue about near-field listening or near-field subs. Thus I replaced the combo by a floorstander loudspeaker featuring D‘Apollito design. Active subs entered the room again not before the purchase of decent room measurement tools.

  3. Dear Paul,

    This doesn’t seem crazy to me at all. It seems like a rational and natural evolution of your recording and playback capabilities.

    I would put subwoofers on a ham sandwich.

    Does this development cause you to think about producing a standalone subwoofer product?

        1. Judging by the sheer gargantuan size of it…

          The Chub Sub
          Butterball Bass
          The Vertebrae Vibrator
          The Pudgy Paunch Prostate Pounder
          The Behemoth Ball Busting Testicle Taser
          Blubber Boomer
          The Stirrup Bone Sizzler
          The Cochlea Crusher
          Rotund Thunder
          Morbid Obassity

          With the Scottish tagline: These subs be shakin meyer brunhavens so hard me eyes are mcgowan crosseyed.

  4. 21” near field subwoofers? Love it!

    My only question is, for this application what defines near field? Are we talking 3 or 30 feet?

    No one ever believes it when they were told that size is not important 🙂

  5. A five string bass guitar B string is usually tuned to 30.9Hz. Drop tuning gets even lower. The lowest note on a standard piano is A at 27.5 Hz.
    Mix in synthesizer infrasound and Dolby Atmos and you can knock people to the floor.
    Call it the “getting floored” test.

  6. Ah, To sub, or not to sub. That is the question!

    I have had my Magico S7’s since 2017. With three 10″ woofers per side and enough power they go down to 20 Hz. I have not had the itch to sub in the five years that I have had them, but who knows. I’ll stay tuned to see how this new release is.

    1. Tony, I’m with you. In my main music listening system I have full-range loudspeakers competent in the down to 16Hz area. I have over the years had several different highly-regarded separate subwoofers in that system, and in every case ended up removing them. They simply did not add anything to the types of music I listen to. I found myself increasingly turning them down in volume, until eventually I just turned them off completely, never missing them.

  7. A few years ago for my digital pipe organ pedal notes I built a large subwoofer using a sonotube 2’dia x 9′ tall and an Eminence Kappa Pro 18″ low frequency driver. I tuned the cabinet volume and ports for strong performance down to 16Hz, the lowest frequency of the pipe organ. The sub works very well in my large room, which opens into other rooms to allow the deep bass standing waves to develop at their full lengths.The wall and celing surfaces are at varying angles to even out the distribution. As the pedal notes approach 16Hz, only the upper harmonics are heard. The deepest bass is sensed as air beating against the eardrums. A 150-watt amplifier is more than enough power to drive the sub without clipping. Needless to say my sub would not win a gut-punching battle with other larger, more high-power subs, but with 28 cu ft and a competent high-efficiency LF driver, it faithfully reproduces the kind of bass generated by 32-foot pitch organ pipes.

  8. Paul,
    I am finding your comments a little too much. I bought both your books. But u supply the high end nuts audiophiles. I bought the Sprout 100 and love it.
    I also have two vintage Marantz receivers. A 2230 and a 2245.
    I bought Elac speakers because u used them.
    How about some products for the rest of us aka not audiophiles?
    Just saying if u can make a living on high end audio? Great.
    But how about the rest of the world?

  9. Isn’t it crazy that the monitoring environment defines the tonality at home so much?

    A dip or a bump in e.g. Octave’s mixing/mastering room means a bump or a dip in one’s room at home (if it’s perfect). If one’s room isn’t perfect (which should be more common) and has opposite dips and bumps, it’s even worse.

    I think even more important than the best FR extension and quality is, that a mixing room has the best possible room acoustic measures directed towards the speakers used. I guess acoustic measures haves to be upgraded when such subwoofers are added.

  10. As a former bass player, I am a fanatic for all musical bassness: Tubas, Contrabassoons, Contrabass Clarinets, Contrabass Recorders, Contrabass Saxophones, Tubax, Bass Viols and String Contrabasses (which come with extensions to C0 or a fifth string at B0), Bass Guitars (especially 5 and 6 string), Chapman Sticks, Tympani, Bass Drums – orchestral 36″-40″ in addition to Rock 24″-28″, Taiko, Marimba Eroica, Ophicleide, Theorbo, Archlute, Bass Harpsichord, Imperial Grand, etc.

    BUT, I had a revelation in December of 1997 when I suddenly heard the UNIVERSAL TIME DISTORTION of all bass speakers. This caused me to return to my pursuit of audio and recording after an 18 year hiatus. Here is what I discovered: most bass instruments can play notes with a rectangular envelope, meaning they go from zero to maximum accleration in sub-milliseconds. Speakers can’t reproduce this because of finite inductance and inertia.

    Dynamic loudspeakers consist of a cone diaphragm with a spring suspension system driven by a linear motor. Because the acoustic coupling to air is proportional to the wavelength over the diameter, the cone has to move farther at lower frequencies. This continues until the resonance frequency (Fs) of the suspension spring constant (Cms) and the moving mass of the cone assembly (Mms).

    The impedance of the woofer reaches a maximum at resonance, which means that the energy is fed into the system slowly, and the movement of the cone is delayed when a note starts suddenly. This not only throws off the PRaT by time shifting the beginning and end of the fundamental, it also frequency shifts the beginning and end of the note, introducing the spurious anharmonic resonance frequency. The common terms for this are ‘group delay’ and ‘spectral contamination’, and they are quite audible once you know what to listen for. Even non-audiophiles can hear it instantly when low group delay speakers are compared side by side with conventional designs. I can hear 2ms of group delay without a reference speaker, a criterion that no commercial speakers systems reach – at least none with realistic bass dynamics.

    Further, the voice coil impedance (Le) typically delays the response of the cone to the driving voltage. The pressure output of a speaker is proportional to the acceleration of the cone, which means it is proportional to the current. Voice coil inductance prevents an instantaneous change in the current, which prevents a pressure transient – like the strike of a bass drum – from being reproduced.

    I have built woofers and subwoofers with low time distoriton, good response to both first order (Dirac) and second order (rectangular envelope) transients, and low transient frequency modulation. There are several ways to do this, but they all require a driver with low Le (<.5mH) and low Qms (<5). Further, they should be in a true infinite baffle (room sized back box), dipole, sealed box with .5≤Qtc≤.65, or possibly a passive radiator 5th order system.

    B&C 21" drivers have low inductance for the oversized voice coil diameter due to the Neo magnets, but they are still four times as much as acceptable for accurate bass rhythm, and have somewhat high Qms.

    My speaker design software, LspCAD, has a simulation option of a rectangular gated sine wave which clearly shows this time and waveform distortion, and it matches real world scope traces. I also used the scope to verify that I could play a rectangular envelope on my Fender bass, and that it was a common musical sound.

      1. While there is no substitution for cone area and air movement, enclosure design is key. AVI (the great Howard Doctor) designed a 6th order bandpass subwoofer for cars that was outstanding. A dual chamber box divided at about 1/4 to 3/4 with the sub mounted internally on the divider baffle; the sound emitting from four finely measured ports – 2 per chamber. There was a 6.5″, 8″ and 10″ version. Even the 6.5″ model could outperform a pair of 8s or even 10s. I still run the 10″ version in my workshop and if is quite adequate for 3000 sqft. I’ve always wanted to build a 12″ or 15″ home version.
        It would also be cool to engineer some sort of full sized home version similar to Shure’s SE846 ingenious sub design:

        LAT and rotary subs have always fascinated me as well.

        I’ve built many sub enclosures over the years, some good an some utterly disastrous. Ports certainly are finicky things… Mind you this was all before box design software came to light.
        Y’know, it’s the ‘having just enough knowledge to be dangerous’ thing…
        I was clearly no Brunhaver.

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