Speaker 'Resonance Frequency' question

Zoolooter

I'm looking at 3 or 4 different low efficiency 10 inch speakers, but take the Jensen P10R and the Jensen P10R-F. One has a resonance frequency of 130hz and the other is 87.3 hz, is this a big or a subtle difference? Will the speaker rated at 87.3hz have tons more mid and bass, or just a tad??? And will the perceived volume be louder with the 87.3hz speaker?

https://www.jensentone.com/vintage_alnico/p10r_f

https://www.jensentone.com/vintage_alnico/p10r

Sporky

Look at the frequency response curves. Most of the difference seems to be in the 2-5kHz range.

Roland

Resonant frequency of the speaker is in the sub bass area. Guitar doesn't have anything useful below about 125Hz. Many people cut these low frequencies to avoid interfering with the bass guitar and kick drum.

The guitar operates above this area. Warmth in a guitar sound goes from about 250 to 650, and the mid range from 650 to 2000. As usual YVMV about what constitutes low, mid and high frequencies.

ICBM

I find it tends to affect the 'looseness' rather than the tone. I don't have any experience with those Jensens, but comparing a 55Hz to a 75Hz Celestion Greenback or G12H-30, the 55Hz ones sound deeper and less damped, so they do seem to have a bit more bottom end 'thump'. I know (standard tuned) guitars don't produce note frequencies below 82Hz so in theory it shouldn't make any difference, but the notes aren't the only factors, there are also the transients from note attack and muting, which go all the way down to a few Hz or less - just watch the speaker cone move when you play and you'll easily see transients move it in and out that slowly.

Sporky

Roland said:

Guitar doesn't have anything useful below about 125Hz.

Isn't the fundamental of a low E around 80Hz? Even the open A string is below 125Hz.

Bygone_Tones

Sporky said:

Roland said:

Guitar doesn't have anything useful below about 125Hz.

Isn't the fundamental of a low E around 80Hz? Even the open A string is below 125Hz.

Low E is around 82Hz, If you are going to downtune to D thats going to be around 73Hz:



The low frequency response is basically the point where the speaker starts to 'come alive' or is capable of producing that frequency.  If you have ever done a sweep tone test on a speaker you will hear this happening. At 0Hz it will be silent, then as you gradually increase the frequency it will get  louder and louder, and start to jump into life when it gets closer to the speaker's frequency range. So that low E 82Hz is probably going to be quieter and less pronounced on the 130Hz speaker than on the 82Hz speaker. The 130Hz speaker is probably more for players who love more mids than bass.

Zoolooter

Bygone_Tones said:

Sporky said:

Roland said:

Guitar doesn't have anything useful below about 125Hz.

Isn't the fundamental of a low E around 80Hz? Even the open A string is below 125Hz.

Low E is around 82Hz, If you are going to downtune to D thats going to be around 73Hz:



The low frequency response is basically the point where the speaker starts to 'come alive' or is capable of producing that frequency.  If you have ever done a sweep tone test on a speaker you will hear this happening. At 0Hz it will be silent, then as you gradually increase the frequency it will get  louder and louder, and start to jump into life when it gets closer to the speaker's frequency range. So that low E 82Hz is probably going to be quieter and less pronounced on the 130Hz speaker than on the 82Hz speaker. The 130Hz speaker is probably more for players who love more mids than bass.

Thank you, now it makes sense! I'm trying to get rid of some of the bass with what I have at the moment, which is a 12' jensen. So my thinking was to go down to a 10", but which 10, because the resonance frequency is all over the place from speaker to speaker, and relying on the db rating does not tell the whole story. This is for home playing but at a decent volume, looks like the Jensens and the WGS 10's with the higher Hz rating would suit because 90% of time I want a clean tone with chime and clarity.

ecc83

How speaker resonance affects "tone" will be hugely influenced by the amplifier. Amps of the Vox AC30 stamp have no negative feedback and a relatively high source impedance (Z) and so have little or no control on the cone.

A meaty 50, better 100 watter with NFB will have a much better "grip" on the cone (one reason you like BIG amps IC?)

Cabinets will also have an effect. A open back cab will just allow the cone resonance to dominate. A closed back cab will have a resonance which is a combination of the enclosed air mass/stiffness AND the speaker Fo. Vented cabs will have two LF resonances and be even MORE affected by amplifier OPZ.

Dave.

Zoolooter

The amp I'm using is a 6v6 12w/6w Bogner head into a pine Bogner 1x12 open cab.

guitarfishbay

Bygone_Tones said:

Sporky said:

Roland said:

Guitar doesn't have anything useful below about 125Hz.

Isn't the fundamental of a low E around 80Hz? Even the open A string is below 125Hz.

Low E is around 82Hz, If you are going to downtune to D thats going to be around 73Hz:

The frequencies are correct and I don't agree with Roland's statement as a fact (because it depends on genre and situation) however I do understand his point about frequencies of bass guitar and kick drums - both of those have to go somewhere.

What is missing from this chart and would give some context is low B on a 5 string bass is about 31hz (to go below an octave you half the freq, to go up you double). A lot of classic bass cabs don't get near that yet still sound great, most people's home listening speakers don't either. Even for the E at 41hz, the classic Ampeg 8x10 is 10db down at 40hz http://www.ampeg.com/products/classic/ If you've ever heard one of these 8x10s you wouldn't say it lacked low end. 

You don't have to have a fundamental frequency loud to hear a note - your ear can determine the pitch anyway if it can hear harmonics (or else listening to music on laptop speakers would be incredibly confusing!). So a pure sine wave of 41hz isn't going to be audible on small speakers but a typical bass string would, because it contains frequencies above it.

The other thing to remember is what filters do. If you were to apply a hypothetical 12db filter at 125hz which I assume is what Roland does, that means it is -12db by an octave below in a smooth slope, not that it completely cuts off at the frequency.