Bass set at 30hz?

[Mushroo]

Are they any benefits at having 30hz on the bass control compared to 60hz?

30hz boosts/cuts the sound 1 octave lower than 60hz (all other things being equal). It is not a question of "benefit" just different numbers and personal preference.

As we have discussed and illustrated with numerous graphs, most 30hz EQ controls will also affect 60hz, and most 60hz controls will also have an effect at 30hz.

 

[2string1]

30hz boosts/cuts the sound 1 octave lower than 60hz (all other things being equal). It is not a question of "benefit" just different numbers and personal preference.

As we have discussed and illustrated with numerous graphs, most 30hz EQ controls will also affect 60hz, and most 60hz controls will also have an effect at 30hz.

So why would one company set it at 30hz and another at 60hz if they both do the same?

 

[Mushroo]

So why would one company set it at 30hz and another at 60hz if they both do the same?

Seriously dude??

 

[gumtown]

Just adjust it to how the tone suits You,
the low-mid (250Hz) control may be of more benefit to you than the 30Hz.

 

[Sid Fang]

A tone control is a filter. It reduces (or possibly increases, with an "active" design) the audio energy in a particular frequency range. A tone control has 3 main properties: the center frequency, the degree of cut (or boost), and the slope or "steepness" of the cut - how affected frequencies are as they approach the center frequency. Without knowing more about the device you're looking at, one can't tell whether it's a control for the center frequency of a bass tone control or a control for the degree of cut/boost at a fixed frequency of 30Hz. Clmayhew and JimmyM guessed differently as to which it is.
Typically, if there's just one knob for the EQ band, it's the cut/bost that's controlled, and the center frequency is fixed (but not always, my bass has a fixed +/off/- 6db midrange cut/boost, with a single knob for the frequency. Weird, but useful).

30Hz is a rediculously low center frequency for a bass tone control, but if the slope of the filter is really gentle, it might make sense. Personally, I suspect that it was put on the front panel because everyone thinks that 30Hz is an important cool bass frequency.

 

[gumtown]

Found this..

• Preamp: solid state preamp with gain, taste, lo, lomid, himid, hi, master controls, switchable mute, DI pre/post, XLR balanced DI out, serial effects loop, tuner out, line out, line in
• Output RMS: 500 w (4 ohms), 300 w (8 ohms)
• Power Amp: Class D
• Power Consumption: 600 w
• Outputs: Speakon® combo connectors with ¼“ jack
• DI Out: balanced, pre/post switchable

• Dimensions: (W x H x D):
  27 cm x 4,4 cm x 21 cm / 10.7" x 1.6" x 8.3"
• WEIGHT: 1,35 kg / 2.2 lbs

Link Removed

The EQ Low control is set at 30Hz +/- 15dB

 

[2string1]

Mine is the older style with the PowerSoft power amp.
Invalid Link Removed

 

[Downunderwonder]

It's an oddball. That's all.

My old Trace 12 band graphic has 30,40,60,100 etc. The 30 slider is red tipped to remind numbskulls not to boost it, mine lives on the floor.

 

[2string1]

I would think it would be useful to be able to cut the 30 if you where in a boomy room.

 

[Bassmec]

I would think it would be useful to be able to cut the 30 if you where in a boomy room.

Boom the room frequencies are from 90Hz up to as high as 300Hz, you would have a very odd room if it had a resonant frequency as low as 30Hz.
Also one wonders how you could get enough energy from a bass guitar cabinet to excite any room resonance at all way down there at 30Hz.

 

[Mushroo]

I would think it would be useful to be able to cut the 30 if you where in a boomy room.

It would, indeed, be useful to cut 30hz or lower frequencies in many situations.

Most players accomplish this quite easily by choice of cabinet. Very few cabinets have "flat" response down to 30hz (and this is not necessarily a bad thing).

 

[will33]

Boom the room frequencies are from 90Hz up to as high as 300Hz, you would have a very odd room if it had a resonant frequency as low as 30Hz.
Also one wonders how you could get enough energy from a bass guitar cabinet to excite any room resonance at all way down there at 30Hz.

+1

Nope. This graph may be fairly similar to what your amp does when you crank full boost on the bass control:

Link Removed

This is just a ballpark model taken from one of my DIY preamps, adjusted to +15dB at 30Hz. You can see that you are actually boosting everything from 1KHz down a little bit. Your amp probably behaves a bit differently, but hopefully you get the general idea? The thread I linked goes into much greater detail if you care to go there.

And this is why amps only used to need a bass and treble control?


OP...as you can see...the "HZ" of the bass knob (or any other knob for that matter), is a reference to the top of a very wide curve. It always spills over into other frequencies. By how much depends on the design.

"Shelving" means it's centered at that frequency bit also lifts everything below it (in the case of bass) and everything above it (in the case of treble). These both also "spill over" into other frequencies.

Midrange controls usually spill over both directions in more of a "bell curve".

As usual, things are not as simple as advertisements or "specs" make them out to be.

In any case, it helps to know what knobs are really doing what, although it's not an absolute requirement in order to achieve good musical tones. "If it sounds good, it is good" applies in each and every case.


With respect to "30hz is a B" or whatever....one of the biggest stumbling blocks I had from playing music my whole life but only getting into the technical aspect of it relatively recently, was to separate in my mind frequency from pitch. They are related, but not the same, and although it makes sense now, it was not easy to do.

 

[BurningSkies]

Not as simple as it seems.

An EQ spec'ed at a 60Hz shelving point can easily still be at full boost at 30Hz, while now slamming another octave of low bass at full power instead of half power at 60 as illustrated in my graph. A little bit of spec is often a dangerous thing, not unlike cranking bass controls in general.

Yep. This is also why I use that HPF3 with the Monique and don't need it with the Kern. The Monique's low is centered around 53hz, but goes way deeper than the Kern's which is centered lower.

 

[2string1]

+1





And this is why amps only used to need a bass and treble control?


OP...as you can see...the "HZ" of the bass knob (or any other knob for that matter), is a reference to the top of a very wide curve. It always spills over into other frequencies. By how much depends on the design.

"Shelving" means it's centered at that frequency bit also lifts everything below it (in the case of bass) and everything above it (in the case of treble). These both also "spill over" into other frequencies.

Midrange controls usually spill over both directions in more of a "bell curve".

As usual, things are not as simple as advertisements or "specs" make them out to be.

In any case, it helps to know what knobs are really doing what, although it's not an absolute requirement in order to achieve good musical tones. "If it sounds good, it is good" applies in each and every case.


With respect to "30hz is a B" or whatever....one of the biggest stumbling blocks I had from playing music my whole life but only getting into the technical aspect of it relatively recently, was to separate in my mind frequency from pitch. They are related, but not the same, and although it makes sense now, it was not easy to do.

Thanks for your explanation. It's very hard for me to understand but slowly getting it. The whole reason I posted my question was because I was reading reviews about the Puma 500 and someone mentioned how they liked the bass pot being set at 30hz and the low mid at 250hz. They seemed to like that combination,but it seems most of you think it's useless and an odd ball to have it set at 30hz...

 

[Passinwind]

Thanks for your explanation. It's very hard for me to understand but slowly getting it. The whole reason I posted my question was because I was reading reviews about the Puma 500 and someone mentioned how they liked the bass pot being set at 30hz and the low mid at 250hz. They seemed to like that combination,but it seems most of you think it's useless and an odd ball to have it set at 30hz...

Not me, necessarily. Everything just has to work together, from your hands to the room, and there are many ways to get there. The standard Bartolini onboard preamp specs 30Hz and models even lower, and is actually quite popular, so...

 

[ThisBass]

In general all those active tone stack filters are of 1st order slope which is +/- 6dB/octave
where the center point is a -3dB point.

Boost of +15dB on 30Hz filter:
+15dB <30Hz
+12dB at 30Hz
+9dB at 60Hz
+3dB at 120Hz
nearly flat at 240Hz

very low filters like 30Hz are very popular in on board electronics and modern preamps.
I'd point a practical and musical sounding center frequency for bass guitar in the range 25..80Hz.

Boost of +15dB on 80Hz filter:
+15dB <80Hz
+12dB at 80Hz
+9dB at 160Hz
+3dB at 320Hz
nearly flat at 640Hz

I myself prefer filters around 50..60Hz.

 

[Passinwind]

In general all those active tone stack filters are of 1st order which is +/- 6dB/octave
where the center point is a -3dB point.

An engineer might (rightfully) spec it that way, but very few MI manufacturers seem to.

 

[Frenchy-Lefty]

I don't know what a Puma 500 is (Google tells me it is sneakers??) but the thread Passinwind links to answers your exact question, with graphs. If you don't have time to read it, I can summarize it by saying: different amps have different circuits, and you should find the one that sounds best to you.

Personally I would probably use a 30hz bass control as cut only. I would never send a signal to the mixing board that was significantly pre-boosted at 30hz, because it would interfere with the engineer's ability to properly EQ/mix my bass using his equipment. Same reason I don't brush my teeth before I go to the dentist for a cleaning.

+1
If any bass gear has a 30Hz eq knob it is most likely a "high pass filter" cutting all the frequencies below 30 Hz (which you can only hear with high end monitors/treated room in addition to a good pair of ears. Although I bet a few show offs on this forum will discent and say they really need and hear those 30 Hz frequencies). To give you an idea of how low 50 hz is already, it is the rumble/buzz you hear when you solo a badly grounded single coil pick on a Jazz Bass.
A high pass filter makes the bass feels tighter and more punchy. If you actually record a bass the sound engineer will often cut the frequencies below 30 Hz.

-1 for the teeth thing though. Your dentist must say "oh boy this dude with the stinky breath is coming for a cleaning again!"

 

[ThisBass]

An engineer might (rightfully) spec it that way, but very few MI manufacturers seem to.

hm, may be you are right but all these filters don't do have a center like a bandpass.
I know it's confusing stuff but theoretically all potential maximum of boost of these active bass filters would be gained only at frequency zero. IMO that is good reason why a -3dB point makes sense.

 

[Passinwind]

hm, may be you are right but all these filters don't do have a center like a bandpass.
I know it's confusing stuff but theoretically all potential maximum of boost of these active bass filters would be gained only at frequency zero. IMO that is good reason why a -3dB point makes sense.

The engineer from Genz-Benz posted about this a while ago when I said the same thing, explaining the rationale for spec'ing the top of the shelf rather than the 3dB point. I'll PM you a link tomorrow if I can find it, I have to go play at an open mike in a few minutes. Anyhow, yeah, it tends to be confusing, like many other specs we frequently see in ad copy. I like graphs, as you may have noticed.