Tiny speakers

[rpjazzguitar]

Can someone explain this to me ... (thanks in advance).

For years I assumed that you needed a decent sized speaker to get a full sound, particularly at the low end.

So, bassists might use 15" speakers and guitarists would use 12". Maybe a little smaller.

But, somehow, the Phil Jones suitcase bass amp sounds huge with two 4" speakers. And, the line array PA's do it also with small speakers.

And, there's the Bud/Blu with a 6" speaker. (For me, not the Lunchbox, which I had and disliked, although others like it).

How does that work? Why, for years, did we only see big speakers and now we're hearing great sound from little speakers?

What is the physics?

[RJVB]

I *think* that using two 4" speakers in parallel makes it possible to approach the sound of a (much) larger speaker provided the 2 are close enough. With the possible added benefit of better high frequency response. IIRC this is why my Klipsch 2-way floorstanders have 2 identical speakers in addition to their horn tweeter.

It's also possible to generate those low notes "between our ears". When presented with the appropriate harmonics series our auditory system will add the root even if it's (mostly) missing. Philips had a range of "ghetto blasters" in which this principle was used but there is no reason why it couldn't be used in a solid state guitar amp.

Well, this kind of sound won't be felt the same way as "the real deal", that might be a reason for some...

[Sam Sherry]

15" drivers might work for rock players. It's been a long time since double-bassists would usually pick them first.

During the mid-70s and early 80s the Top Player setup was a Walter Woods MI-100 into 2x Bose 802s.
Me too, following far in back of their footsteps.
8x 3.5" drivers per box
Not very efficient but a mighty fine sound indeed.

After that I went up to a WW MI-225 amp into Euphonic Audio VL-208 boxes. 2x 8", 2x 3" midrange, 1x tweeter.
Perhaps the most accurate DB speakers ever. I ditched my when parts got scarce, and yeah, 45+ pounds.

Today I run a WW MI-100 into one or two Euphonic VL-110 boxes. Very nice, very hifi, a drop warmer than the 208s. About ten pounds lighter too.
Euphonic Audio is out of business so I will run the 110s into the ground and then worry about what comes after.
I have a Euphonic Wizzy 12 that sounds nice and is lighter than the VL-110s, but it's more mid-forward and less hifi.

[Gitterbug]

A few, possibly incongruent points:

- Speaker technology has made advances. Look at car audio stuff: very small speakers with frequency ranges from 40 Hz. 6.5" is a standard size there, so probably much more R&D spending there than around instrument speakers.
- Amp power was a scarce resource during the tube era. Exceeding 100W was tantamount to running a thermal power station. Large, efficient speakers compensated for that. Now Class D amps achieve very high wattages, providing enough power for smaller, less sensitive speakers. You may argue that tube watts are different, i.e. that I'm comparing a fire hose to a pressure washer, but if the latter does the job, why not?
- Less stage volume is needed. Venues have PA systems, so the backline has more of a supporting role. Also, mature audiences have had their share of ear-piercing noise at live music bars; they want to babble and toast while enjoying music. Discos, raves and rock festivals are a different animal, yet ecstasy again catered for by PA systems (and eventual chemical additives.)
- Personally, I like the feel and response of a small speaker. Having used my own Metros on most occasions lately, I recently felt uncomfortable even with a 10" Toob in an auditorium seating 600. A 25W Quilter Superblock gave it more than enough oomph.

I believe that, especially for jazz guitar and blues, 10" will eventually replace 12" as the benchmark, unless the trend towards smaller expands the 6.5" and 8" speaker offering even further.

[ccroft]

I'm clearly not an audio engineer, but if we were comparing a Fender Twin to a Blu 6, for EG: the Twin is an open back cab and gets much of it's low end off the back of the speakers, where the Blu is a closed and ported cabinet. The port provides the low end.

Ported cabs have been around forever. Why it's becoming more popular now still stands.

And there's those aluminum cone bass cabs that started in the 80's with 4 or more 8 or 10" speakers. I remember wondering the same as RP when I played with a guy who used one: "how the heck are these tiny speakers producing so much bass?" I think those were sealed enclosures. I'm not sure how sealed cabs get their low end. The Quilter 8's were also sealed.

I think these small speakers may also have some other physical differences from what we normally think of as a guitar speaker. Like maybe the geometry of the cone, the voice-coil, and the throw.

[pingu]

my understanding of the Physics

small diameter speakers can produce low notes fine
eg bookshelf Hi Fi speakers etc etc

but are less efficient at producing the low frequencies so one needs very high power with good cooling

modern engineering has enabled this

you need a High power amplifier and multiple drivers , depending on how loud you need to get

see Phil Woods bass cabinets
High power Amps etc etc

as an advantage small speakers have the advantage
of being very fast and they can ‘stop’ quickly

good for a nice controlled bass sound
without too much flapping about on the end of the note

great for funky bass etc

[pingu]

low E on a guitar is 82 hz

It seems that this can be produced fairly well on a small speaker
even without a huge amp

this is at Jazz gig type volumes ....

which is handy

[sgosnell]

It's all in the ports. Bose started doing that, getting good bass response from small units with complicated porting.

[EastwoodMike]

I'm no expert but from what I understand having listened to a great interview with the current R&D manager of Jensen speakers-

Closed back = increase speaker damping = stiffer crisper bass response
High speaker damping = more wattage to move speaker cone.


Bass is largely directionless- which is why you can park your woofer anywhere in your living room, so higher end "boxiness" becomes less of an issue.
Treble is more directional- closed back can become beamy. Combining with an array this I understand can increase the beaminess to end up with the classic Marshal stack laser beam.
The effective (resultant) distance from baffle to cone center is someplace behind the speaker drivers in a 2x2 array or so I have been told.

Line arrays for PA systems work slightly differently and are optimised somehow to increase dispersion. I have read that a Horizontal 2x12 has different dispersion to a vertical 2x12 but have owned neither.

Again, no expert but I take advise from Internet with a grain of salt anyway. The Jensen interview was probably the most informative

Cheers
Michael

[Hammertone]

Bah, humbug.

[KirkP]

Advances in ported cabinet design are part of it, but speaker drivers have also advanced to handle lower frequencies at higher power levels. Modern voice coils can handle higher temperatures without melting or warping and cones can make larger excursions without distortion or damage.

[Woody Sound]

I play occasionally in a loud funk-rock big band, who's bass player uses 4 older Bose speakers stacked vertically. I should take a picture of it next time. I *think* he uses a Woods head. Super clear, crisp sound with a lot of bottom.

If my math is correct, that's 4x8= (32) 4-1/2" speakers.

[sgosnell]

I have a set of Bose 901 speakers, acquired sometime in the '70s, and they have 9 speakers in each cabinet, one firing to the front, the rest to the rear. They came with an equalizer, highly recommended because they increased the treble response, which was insufficient for many people, although plenty of bass. They're still in use in my living room, mostly for use with the TV, although a Google Chromecast Audio is also connected to the amp. Great speakers, still sounding very good. I've tried using a soundbar and other newer speakers, but I keep going back to the 901s.

[nevershouldhavesoldit]

I have a set of Bose 901 speakers, acquired sometime in the '70s, and they have 9 speakers in each cabinet, one firing to the front, the rest to the rear. They came with an equalizer, highly recommended because they increased the treble response, which was insufficient for many people, although plenty of bass. They're still in use in my living room, mostly for use with the TV, although a Google Chromecast Audio is also connected to the amp. Great speakers, still sounding very good. I've tried using a soundbar and other newer speakers, but I keep going back to the 901s.

The 901s require the associated electronics to produce a relatively flat frequency response - without it, their FR is basically a huge midrange hump. I’ve never found a response curve for the passive cabs themselves, but they’re seriously deficient at both ends of the spectrum.

Given the lower limit of a 6 string guitar at about 82 Hz, they work as guitar speakers - but to me they’re flat and lifeless. And they’re not useful for PA or sound reinforcement without heavy EQ if the Bose box is missing. Most who use only the cabs use 31 band EQ to get decent sound quality.

[sgosnell]

I've never considered using them as guitar speakers. I don't really hear much difference with or without the EQ box. I have it, but don't bother to use it. Maybe it's my ears.

[BigDaddyLoveHandles]

The OP mentions Phil Jones cabinets:



Folded horns also bring the bass, eh?

Hard to see, but those are 5" speakers (and side ports):