Improving Bass Control

Decide on how much Bass you want and what the room can support. Choose a Power Amp that will drive the speakers that deliver that bass. Choose a Pre-amp that will have the quality bass needed for this. Choose a source capable of delivering it all in the first place!

This may sound 'the wrong way around' - but the Bass is being discussed here and the more extension you want, the bigger the demand on everything else up the chain. If you just want clean tight bass with not so much deeper bass, then everything becomes easier and you have a wider range of choices.

I wanted a full-range system and I found that puts big demands on everything.

For example: Get an Power Amp that has a regulated supply, so the NAP250 is the minimum for that. Then  good Pre to feed that with decent enough supply, so a 252 with Supercap would fit, as would a 272 with XPS or better a 555PS. Digital sources are easy once you have a good Pre and good Pre-source cables.

As to room-correction and traps - last on my list! Don't like what room-correction does to music and prefer to position room-furnishings to obtain enough loss and traps to give what I need. In difficult 'boxy' rooms traps may be the way to go and I defer to those with the experience with that.

But my experience is that lots of so-called 'room-resonances' go away when a better Power Amp is used and the equipment is placed on Fraim.
What is usually called room-resonances are often cured when less colouration distortions are pumped into the room in the first place, rather than controlling it after it is dumped into the room.

DB.

What DB refers to is primarily a sub-harmonic bass. A typical bass-guitar will go down to approximately 32Hz on a low B string. That is practically the lowest note for a modern rock / jazz etc.

All notes produce upper harmonics, which give us a feeling of spacious, airy etc sound. Lower harmonics are the ones that massage your spleen at rock concerts Difficult to replicate in a domestic environment and even more difficult to control. Sound waves of that length require large amounts of power to sound good and well controlled. Otherwise what is going to be heard is a woooly, mushy sonic boooom.

On my bass rig, I need 600Watts of class A power, with a 15 inch bass speaker, supported by at least 2 10" speakers and high frequency horns, to get it sound clean. A bit of an unlikely proposition for home use

I've found that the better the Power Amp, the less wide-band harmonic distortion being pumped into the room - and the cleaner and crisper the presentation. For example, when I upgraded from Passive speaker operation to Active speakers I had less 'room-resonances', as there was vastly lowered harmonic distortion. Then the same happened again when I swapped my set of NAP300 Amps for a set of NAP500 Amps - the extra grip and control gave more powerful real bass and less 'distortion bass'. But it is not just bass, but all harmonics on and up to the highest frequencies you want to consider audible.

Either you do the job properly with the right equipment - or you decide to transduce less bass into the room and accept that different distortion effect for a reduction in harmonic distortion - or you decide to chase-down and attenuate what you pump-in to the room - or try to digitally-remove it from the signal and accept what that does.

Best not to have the problem in the first place - but then welcome to the HiFi crazy universe!

DB.

Adam Zielinski posted:

What DB refers to is primarily a sub-harmonic bass. A typical bass-guitar will go down to approximately 32Hz on a low B string. That is practically the lowest note for a modern rock / jazz etc.

All notes produce upper harmonics, which give us a feeling of spacious, airy etc sound. Lower harmonics are the ones that massage your spleen at rock concerts Difficult to replicate in a domestic environment and even more difficult to control. Sound waves of that length require large amounts of power to sound good and well controlled. Otherwise what is going to be heard is a woooly, mushy sonic boooom.

On my bass rig, I need 600Watts of class A power, with a 15 inch bass speaker, supported by at least 2 10" speakers and high frequency horns, to get it sound clean. A bit of an unlikely proposition for home use

Rather it is bass fundamentals, not sub-harmonic, though yes that is sub harmonic...

And whilst the point about bass driver size is relevant to live gig playing, domestic bass reproduction is rathe different if only because the output required into a domestic living room is likely to be considerably less than even a small hall full of people - but clean and extended bass does tend to dictate physically large and relatively expansive designs, but that is the cost if it is what the listener wants. And indeed the rest of the system providing adequate control.

For me, i could not be happy with a system that curtails the bottom notes giving just the harmonics, but that is personal taste, and has been with me since I first heard music live, and drove my pursuit of a replay system. That doesnt mean I cant enjoy mysic from a lesser system - if it is good music it is surprising how poor reproduction still enables enjoyment, just it is more satisfying having it all in full.

Darke Bear posted:

 

...

For example: Get an Power Amp that has a regulated supply, so the NAP250 is the minimum for that. Then  good Pre to feed that with decent enough supply, so a 252 with Supercap would fit, as would a 272 with XPS or better a 555PS. Digital sources are easy once you have a good Pre and good Pre-source cables.

As to room-correction and traps - last on my list! Don't like what room-correction does to music and prefer to position room-furnishings to obtain enough loss and traps to give what I need. In difficult 'boxy' rooms traps may be the way to go and I defer to those with the experience with that.

But my experience is that lots of so-called 'room-resonances' go away when a better Power Amp is used and the equipment is placed on Fraim.
What is usually called room-resonances are often cured when less colouration distortions are pumped into the room in the first place, rather than controlling it after it is dumped into the room.

DB.

Sorry DB, I disagree.

Regulation within the power amp isn't necessary for good LF response, it's just one of the available solutions.

The degree of room correction and bass trapping obviously does depend on the room.  However ALL rooms have 1/2 wave resonances and those are almost completely unaffected by the damping factor controlling the LF speaker cones - they are fundamental to the acoustic physics of the room (not related to the amp or speakers).

In my experience of designing power amps, the lower distortion is mostly related to the better amp generating much less IM distortion (particularly TID) and to a lesser degree lower higher order harmonic distortions.

Of course Mike.  The recorded music contains a lot of sub-harmonic / low frequency sound, well below a bass guitar. Hence a domestic unit will need to handle them as well.

ahhh - joys of music

Mike,

What is "Power Rating", and even more questionable, what is "Music Power"?

P.S. I understand RMS power and peak power!

Huge posted:

Sorry DB, I disagree....

I understand what you are saying and don't disagree with what you say about room-physics!

But I think you have missed my point. The less power in the rubbish from harmonic distortion that is put into the room to excite the room, the less problem you have with it. It is what I have observed over about 40 years in HiFi - a friend of mine back in my college days was plagued with 'room-resonances' until he serviced his power-amp and was amazed that his room-resonances went away.

Obviously they are still there, but they did not detract from the music anymore, as there was less non-music power being put into the room from the reduced distortion and more music. When I upgraded my system recently a Forum friend told me I was listening to music at a lower volume level - but in fact it was the same level of music, but all the mush of distortion was gone.

But I've introduced my point to the discussion to fix the 'problem' before it happens. It is a ratio of 'room-resonance' to music - more music makes things go better. I'm really not having all these problems and I have no room-correction or traps.

DB.

Adam Zielinski posted:

Of course Mike.  The recorded music contains a lot of sub-harmonic / low frequency sound, well below a bass guitar. Hence a domestic unit will need to handle them as well.

ahhh - joys of music

I have always held the view that the lowest pitch that needs to be reproduced is the bass fundamental of the lowest notes made by conventional acoustic instruments. Though there are lower pitches in performance halls, these are of no musical significance what so ever.

As has been noted the lowest musical note has a pitch in the region of 32 Hertz.  It is musically beneficial that no lower pitch is attempted in replay, and this is something that can allow replay to be so musically satisfying. The lower frequencies that abound are beneficially left out of replay. 

I do realise that there is another octave that is the province of the pipe organ - down to about 17 Hertz - but as these are inaudible as a pitch, they are irrelevant and only used in music of dubious value. The 32 foot pipe ranks of an organ produce these inaudible tones. 

It is fascinating to me that in a moment of weakness I have tested pure sine wave pitches from 17 Hertz upwards, and as the ESL is so free from harmonic distortion it becomes clear that while the speaker can excite a window or a letter box, the sound itself is inaudible to the human ear directly to about 32 or 33 Hertz. Therefore replay should beneficially actually positively ignore studio recorded frequencies below this 32 or 33 Hertz point. Such infra-bass is positively a bad thing! It has nothing to do with music. Only sound.

Equally nothing useful from the musical standpoint occurs above 14 to 16 K Hertz, so an early close down of high frequencies can not only safely be adopted, but it is positively beneficial in home replay ...

ATB from George

Dear George,

My hearing goes down to 23Hz and I do listen to some organ music (as well as [horror of horrors] some electronic music), so response below 32Hz is useful to me.

Huge posted:

What is "Power Rating", and even more questionable, what is "Music Power"?

P.S. I understand RMS power and peak power!

I had the data handy from two units I was working with last year;  both makes used the same rating terminology,  I assume its US numbers,  I copied it to make my point that hifi drivers are nothing like those used for music units.  

All my speaker work has used IEC ratings.  It looks like Power Rating is similar to RMS (IEC DIN) & the other is peak.   

I think it is beneficial to have those sounds, but dettecting a pitch in that low range is extremely difficult. 
Out of practice I can just about tell a low B (lowest open string of a 5 or 6 string bass). In a context of music being played, I tend to more sense it though (especially if I hit a bum note ).

I used to play the orchestral double bass both as a professional and as a teacher of the instrument. I had a five stringer made in 1994/5, and this of course had the low “B" in its compass.

In truth the low “C” a semitone higher is significant, and is quite different in effect from the “C” that is the bottom note of the cello, and easily replicated on the double bass on the “A” string. But there is absolutely no musical value in reproducing pitches lower than the fundamental of the lowest playable notes. The rest is just studio or concert hall sonic pollution, not less toxic than dioxin from burning plastics in a bonfire!

Best wishes from George

Or just get a Linn DS.

Here is a great piece of music where the double bass plays a pedal “D” - right at the start - one whole tone above the “C” we are considering as a semi-tone above the lowest real note ...

You do not need anything very extravagant to reproduce this low “D” well. My Tivoli Model One kitchen radio does it well with a two and ahalf inch driver ... The ESL does it supremely well. Better than any coned bass speaker.

Handel’s Organ Concerto in D Minor Opus 7, Number 4:

https://www.youtube.com/watch?v=SDopQ0e9R8Q

ATB from George

Ummm...  A Drum impact is "broadband" and can perhaps contain energy below the fundamental of a string bass.  As has been noted, it takes an expensive system to produce convincing reproduction of the bottom octave of music.  Always a compromise.

CharlieP posted:

 it takes an expensive system to produce convincing reproduction of the bottom octave of music.  Always a compromise.

Even if you can afford it, who actually has the room for it? Literally, the room - how long is that wave? Besides, the typical hi-fi enthusiast can listen to how much pipe organ music in the course of a day? Low bass starts to get a bit like the super-tweeter discussion to me.

joerand posted:

CharlieP posted:

 it takes an expensive system to produce convincing reproduction of the bottom octave of music.  Always a compromise.

Even if you can afford it, who actually has the room for it? Literally, the room - how long is that wave? Besides, the typical hi-fi enthusiast can listen to how much pipe organ music in the course of a day? Low bass starts to get a bit like the super-tweeter discussion to me.

Charlie,  My system isn't expensive (by the standards of this forum anyway!), yet it has flat response to below 18Hz (+-3dB, 1/3rd octave) (but I still regard anything below 23Hz as irrelevant for me, as that's the lower limit of my hearing).

Joe,  You don't actually need a large room, just a transducer that will couple to the room and generate pressure variance in the whole room.  Subs are designed to do exactly that.  The lowest fundamental resonance in my room is 39.4Hz, but I get a flat response a full octave below that.  Also Charlie was right about some drum sounds having very low frequency components.  There are also quite a few pieces of electronic music having bass frequencies in the region 25Hz-32Hz and reproducing these properly can significantly contribute to the music.

George Fredrik Fiske posted:

I used to play the orchestral double bass both as a professional and as a teacher of the instrument. I had a five stringer made in 1994/5, and this of course had the low “B" in its compass.

In truth the low “C” a semitone higher is significant, and is quite different in effect from the “C” that is the bottom note of the cello, and easily replicated on the double bass on the “A” string. But there is absolutely no musical value in reproducing pitches lower than the fundamental of the lowest playable notes. The rest is just studio or concert hall sonic pollution, not less toxic than dioxin from burning plastics in a bonfire!

Best wishes from George

What frequency would that be ?

engjoo posted:

George Fredrik Fiske posted:

I used to play the orchestral double bass both as a professional and as a teacher of the instrument. I had a five stringer made in 1994/5, and this of course had the low “B" in its compass.

In truth the low “C” a semitone higher is significant, and is quite different in effect from the “C” that is the bottom note of the cello, and easily replicated on the double bass on the “A” string. But there is absolutely no musical value in reproducing pitches lower than the fundamental of the lowest playable notes. The rest is just studio or concert hall sonic pollution, not less toxic than dioxin from burning plastics in a bonfire!

Best wishes from George

What frequency would that be ?

B0 is 30.87Hz.

joerand posted:

CharlieP posted:

 it takes an expensive system to produce convincing reproduction of the bottom octave of music.  Always a compromise.

Even if you can afford it, who actually has the room for it? Literally, the room - how long is that wave? Besides, the typical hi-fi enthusiast can listen to how much pipe organ music in the course of a day? Low bass starts to get a bit like the super-tweeter discussion to me.

 

I don't understand this view: if you needed a room larger than the wavelength of sound to hear it, then headphones wouldn't be capable of reproducing sounds lower than at least several kHz. And what does it matter how long someone might listen, if what is important is hearing (& in the case of the low bass also feeling) the music as intended? 

I agree, however, that there is effectively a 'law of diminishing returns', so that for lower, especiially well-controlled, bass, systems can get pretty expensive, affording/justifying which can only be a matter for an individual listener to decide.  A if this question is turning to consideration of 'low bass', it begs a definition:  My Interpretion of 'low bass' is just  the bottom octave,  below 40 hz (recognising the most common lowest tuning of bass guitars and double basses being 41Hz), being where feeling the sound becomes as significant as hearing.

For me, I wouldn't consider a system to be in the least satisfying if it can't reproduce without diminishing (in situ) at least down 40Hz, and really want it down at least to 32Hz, while I can fully understand people wanting lower if they have a penchant for fullrange organ or synth music. I believe the lowest pipe organ fundamental is 16Hz - which is a definite 'feelie' but live lowest pipe organ bass is not 'fast', so if the concept of bass control as raised by the OP is instant-on, instant-off, I suspect it ceases to be so relevant down at the feelie level.

Huge posted:

engjoo posted:

George Fredrik Fiske posted:

I used to play the orchestral double bass both as a professional and as a teacher of the instrument. I had a five stringer made in 1994/5, and this of course had the low “B" in its compass.

In truth the low “C” a semitone higher is significant, and is quite different in effect from the “C” that is the bottom note of the cello, and easily replicated on the double bass on the “A” string. But there is absolutely no musical value in reproducing pitches lower than the fundamental of the lowest playable notes. The rest is just studio or concert hall sonic pollution, not less toxic than dioxin from burning plastics in a bonfire!

Best wishes from George

What frequency would that be ?

B0 is 30.87Hz.

I thought the lowest note on a piano is A0, 27.5Hz?

The bottom octave on most pianos is fairly toxic! The bottom note almost always so!

ATB from George

George Fredrik Fiske posted:

The bottom octave on most pianos is fairly toxic! The bottom note almost always so!

ATB from George

Dear George, as a chemist and a biologist I do find the idea of toxic notes to be an interesting concept.