why do amp specs never show what is lowest note they can perform?

[bholder]

It usually takes multiple cabinets, and drivers that are designed specifically for subwoofer duty (which will have awful mid bass and mid response) and will not be all that efficient as well.

My main PA rig uses 12 JBL SRX-718 subs, and about 10kW of power. Clustered and ground coupled in half-space, it can do maybe 120dB/1W/1M at 20Hz with the proper processing (though can do maybe 132dB at 40Hz). This application would demand a high Q high pass filter set just under 20Hz otherwise the drivers would tear themselves apart. This is pro level gear, about $20k worth just for subs, power and processing.

Yeah, definitely "beyond my pay grade". I'm sure that'd do it, though!

 

[Korladis]

You can always duck the bass on the kick. Even though I hate that. But then I hate weedy clicky kick drum sounds as well. Actually almost everything about rock is irritating except for bass.

Yeah, I prefer to have the kick have sub-low frequencies, then high pass the bass guitar and gradually add lows back into it until just before it gets muddy.

 

[SanDiegoHarry]

I just wonder why no amps specs show what is the lowest note it can produce
E.g. A 10 watt amp can not produce sounds under 200 hz properly.

Physically, the bigger the speaker, the better it will "disturb" the air genarating this huge vibrations we call "low frequency sounds"

Studio monitors, headphones, even mics, show their frequency responce, but not the Amplifiers

Well... some of it is kinda obvious. A 10 W amp with a 8" speaker is not relaly what you're looking for.

Speakers usually list their dynamic range - but little combo amps aren't really meant for more than at-home practice.

 

[Deleted member 165050]

I just wonder why no amps specs show what is the lowest note it can produce
E.g. A 10 watt amp can not produce sounds under 200 hz properly.

I'm sure someone has already said this but in case they haven't, frequency response is not a function of output power capacity. There's nothing stopping a 10 watt amp producing low frequencies...

 

[sawzalot]

Opening popcorn...

Tom

 

[Engle]

Is just that people are not listening to that low E on the amp but the harmonics
And the first harmonic, is and octave...
Which means if you are playing 41 hertz on an amp that can not produce the you will hear instead the first harmonic: 82 hertz

And as every sound we play thru our basses has its fundamental and at least 6 quite noticeable harmonics, they do not miss when the fundamental doesnt sound.... it is crazy

Yes peoples perceptions of sound often don't make sense. There are a lot of variables!
The environment that you place the cabinet in is one. Where the listener is in the room is another.
And the signal coming from the bass is a lot different that of a frequency generator.

 

[Mugre]

since the biggest, most powerful concert subwoofer systems don't do that, i doubt you'll find one or really need it.

It's not that a dual 18 can't. They can but in the design they trade that extra octave on unnecessary rumble for efficiency.

Bag End makes a series of of speakers called infra subs that go to a usable 8-12 hz using an electronic "integrator".

Mugre

 

[tfer]

The only way to properly audition an amp, is to bring your bass with you, plug in, and turn up.

Frequency charts can't possibly account for your instrument and playing style.

 

[Korladis]

It's not that a dual 18 can't. They can but in the design they trade that extra octave on unnecessary rumble for efficiency.

Bag End makes a series of of speakers called infra subs that go to a usable 8-12 hz using an electronic "integrator".

Mugre

Indeed. Most bassists likely wouldn't find that low end extension to be worth the trade-offs necessary to get it.

 

[fdeck]

Seriously? What casual player has equipment and knowledge to test a frequency response curve of an amp?

I play a lot of casuals.

 

[Stewie]

Someone is about to bring two JBL 18 inch subs to our practice space. I bet I can explode my upright to tiny splinters with feedback using those suckers.


Except, I use the last poster's HPF set at something like 60 Hz to stop the rumbling

 

[agedhorse]

What about HPFs anyone?

Used widely on recordings and live. See fdeck or the omni cab sim.

I thought we wanted loud and light these days...

Sure, of course. Every amp I have designed in the last 15 years has had one (of one kind or another). It's technology that's been around for a very long time in the pro audio world too.

 

[fdeck]

I am not trying to offend anybody, English aint my native language. I am a foreign student, currently on MIT. And I play. So, when you go the lab every piece of equipment has manuals with very detailed info about its components and their behaviour. And it just drives me crazy that musical equipment do not follow those standards, because honestly It would make people's choices easier.

People not knowing how to read a graph does not seem a valid reason to not include that information.

I sympathize with the frustration. I live in both worlds: By day I work for a company that makes scientific instruments, and so I help create the specs that go into those equipment manuals.

I decided to take matters into my own hands, and learn more about how bass gear works, so I can make my own educated guesses about things like speaker response. I also enjoy making things, so I started designing my own speakers. My "non commercial" web page has some articles that I've written on the subject, including a derivation of the formula for the speaker response curve. You might enjoy it.

 

[R Baer]

I'll link to a pair of EBS combos I'm interested in. Invalid Link Removed

The frequency response of each configuration is listed. The 15" speaker version says:

• Frequency Response 30 - 20k Hz

The 210 version says

• Frequency Response 50 - 20k Hz

These numbers by themselves are actually fairly useless. For example it states Frequency Response 30-20kHz. Is that 30-20kHz @ -3dB or maybe 30-20kHz @ -10dB. Maybe it's -20dB? Without listing that crucial bit of info, the frequency response itself doesn't really tell you anything.

 

[DigitalMan]

Most people assume the cab size as part of the equation, which makes sense because in days of old bigger speakers usually came in bigger boxes. However, the market is now filled with compact cabs lines, where the enclosure size is minimized in order to save weight and make them more portable. Assuming a 15" speaker will come in a similar/proportionally sized cab across all manufacturers and product lines is not what it used to be. I've had two cabs from the same builder, using the same driver, and one was more compact, with noticeably different low end characteristics.

The same holds true with bare speakers from the same manufacturer and product line providing the definition of the product line truly reflects a common build paradigm and isn't just a marketing vehicle.

 

[Gizmot]

I'm sure someone has already said this but in case they haven't, frequency response is not a function of output power capacity. There's nothing stopping a 10 watt amp producing low frequencies...

A 10 watt amp can (or should) be able to amplify low frequencies, but it needs a properly tuned, high efficiency speaker to reproduce the signal accurately.

 

[JimmyM]

If we want that kind of bass response, why are we looking at practice amps?

 

[trowaclown]

So...OP comes in complaining about the lack of information, and asks why companies don't publish such information, because she believes that they will help a player make better buying decisions. But OP actually misinterpreted the data, and when told that, said that she read the data that way because it was implied that way, when it wasn't.

Next, OP made grossly sweeping statements, such as the relationship between speaker size and the frequency the cabinet can produce. When corrected on this, she defended herself saying that she was trying to be "as simple as possible", because "there is always exceptions to the rules".

I think our OP has answered her own question here: specs are NOT published because they can be misinterpreted by players like herself, and complete information that includes details such as dispersion is so nuanced that that they will probably fly over the heads of people asking for them.

 

[-Asdfgh-]

I just wonder why no amps specs show what is the lowest note it can produce
E.g. A 10 watt amp can not produce sounds under 200 hz properly.

Physically, the bigger the speaker, the better it will "disturb" the air genarating this huge vibrations we call "low frequency sounds"

Studio monitors, headphones, even mics, show their frequency responce, but not the Amplifiers

Do you mean amp or cabinet? A 10 Watt amplifier can easily produce sounds under 200Hz, it's the cabinet that might not be able to project them.

Many cabinets quote frequency responses, but it's not always clear if it's +-3dB or +-10dB ranges, those being most common. Some quote maximum SPL, but not necessarily the weighting.

 

[superdick2112]

The only way to properly audition an amp, is to bring your bass with you, plug in, and turn up.

Frequency charts can't possibly account for your instrument and playing style.

+1000
The same holds true for basses & pedals.
Specs tell only a little, reviews are a bit more helpful, but nothing tells you more about a product than actually laying hands on it.