John Curl's Blowtorch preamplifier part II

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Lots of bass in music

This is completely misinformed about music containing bass. Most record sales are not in Classical. If all you listen to is classical music, you wont find a lot of bass, that is for sure.

In all other forms of American music you will find a bass player in the group of musicians. Jazz, Blues, Rock, Gospel etc. The old standard is the upright acoustic bass and the 4 string electric bass. The highest fundemental tone on the standard bass is under 100 Hz (98Hz).... The lowest is 41.2hz. If your system is -X DB at 50-60Hz, you are missing the full first two tones on the basic 4 string bass guitar (E and A string). You miss the accurate reproduction of the sound and the musical rhythm and foundation of the music.

Since 1956 (Danelectro) and 1961 (Fender) the five string bass has come into popular use. That is the added B string at 30.87Hz. From Wiki- "... the deep sounds of the low B string has become a standard in many genres..."

If you love all forms of music... get in tune yourself and get some quality bass in your system.

-RNMarsh
 
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Pretty much every classical orchestra line-up have a doubla bass

Classical Orchestra
2 Double Basses

Early Romantic Orchestra
6 Double basses

Late Romantic Orchestra
8 Double basses

Modern Orchestra
8-10 Double basses

These are tuned with a E1 = 40 Hz some even are 5 stringed with B0 = 31Hz

/Anders
 
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http://en.wikipedia.org/wiki/Imperial_Bösendorfer_(piano)

When I was a student the late great Natalie Limonick lectured from the piano in one of the classrooms at UCLA that housed an Imperial Concert Grand. This one had the cover for the lower extra keys.

Some of the students used to sneak over while Natalie was looking in the other direction and lift the flap on the bottom of the keyboard. When she went back to playing musical examples she would plunge down to play a low note and curse as she missed it :)
 
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Not a lot... means: not a lot. it doesnt mean I said zero. I didnt write -- "such freq are rare. Nor Almost nothing on most recordings". Compared to the many other forms of music -- bass is a lot more often being played and thruout the entire tune/score. I have a piano in my home... I know it has bass. Even classical piano music scores rarely use the lowest tones (they are very hard to keep in tune). I added in other genre to indicate there is a lot of bass being played and recorded.

To indicate that you wont miss bass with speakers that cut it off -thinking there isnt much to miss anyway or it isnt in the score of a lot of classical music as was shown, is not about the Hi-End IMO. Your speakers need to cleanly go down to 30Hz, at least, to capture all the music recorded; especially heavy bass content in the more popular genre's. So, get on board. When you are -- you will also find low power amps dont cut it for bass drivers (unless you have a stupendous bass Horn speaker). -RNM
 
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What you find is that most rock and r and b is played between low g and the g above it on the bass guitar, this is the chest resonant region.

In a live situation it is accompanied by a bass drum with a fundamental in the 30Hz. region, the gut resonance.

When bands like the who started to use large amounts of sound another thing came into it, and this is the production of bass sub harmonics.

What happened however is that record companies wanted to get more on a side and the cheap record players most people had could not track any low bass, and the reproduction equipment could not reproduce it anyway, so for the most part the low bass content was cut, and in some instances, the Motown sound for instance, the bass was equalised to a punch region peak.

What also happened is that the large concert with huge p.a. systems also became the norm, and these were restricted to a lower cut of in the 50-60Hz. region, ( with a few notable exceptions), and this sort of thing became the norm for most people.

Sound people know that you only need to go down this low to satisfy most people, and it is a lot cheaper to buy and transport, and removing the front skin from the bass drum was a common practice, this pushing up its frequency so it could be heard on the p.a.
You can hear a lot more of what the original sound was by listening to later c.d. versions, since the c.d. format allows much more bass content with no penalties. These have pretty much what was record in the first place and then limited and cut etc. to suit the vagaries of vinyl.
rcw
 
To indicate that you wont miss bass with speakers that cut it off -thinking there isnt much to miss anyway or it isnt in the score of a lot of classical music as was shown, is not about the Hi-End IMO. Your speakers need to cleanly go down to 30Hz, at least, to capture all the music recorded.
2 points.

1) If you've never been to a live orchestral concert, one of the most impressive things you'll notice on your first visit is the quantity and quality of the bass.

2) I've got well over a decade's worth of Double Blind Listening Test results ala Lipshitz & Vanderkooy bla bla, mostly on loudspeakers.

One of the most important facets of our tests is the victim chooses his own music. He (may be female) needs to provide at least one sample of simple, complicated, vocal, instrumental and combinations of these making at least 5 pieces but they can be all pop/classical/etc. The important thing is it must be stuff he listens to for his own enjoyment. But he is free to choose as many as he wants and take the whole day to do the test. Each victim is tested alone.

I do ABC tests rather than ABX cos you get statistical significance faster.

The speaker which came out best is a small 5 ltr vented box with a known LF cutoff of 70Hz. It has beaten much larger & more expensive speakers with much more LF extension and invariably receives favourable comments about its LF performance compared to these including 'more extended .. bla bla' even from speaker designers & recording engineers.

Hardly anyone listens to Also Sprach Zarathustra for pleasure ... and for those who do, the opening is just one part of the whole piece.

And a speaker's LF performance below 70Hz is only one facet of 'bass' performance.

I'm not disputing what is necessary to 'capture all the music recorded'. (I used to have a list of records with music where LF below 40Hz were important and have designed commercial speakers for significant power at 16Hz.) Just what is important for listening pleasure.

It is possible to get good LF performance down to 40Hz and still retain other important speaker qualities in a box of sensible size .. eg 40 ltrs. Going below that really requires a separate subwoofer handling only stuff below 40Hz.

BTW, there should be stereo 'subwoofers'.
 
Point taken on forms of popular music that may deliberately use the lowest notes more often compared to classical.

But, I wonder ... if I took one of those tracks and digitally excised the frequency content below 50Hz using an extreme cutoff slope, and had people with optimised bass behaviour on their systems AB the original and edited track, how many would pick it? In other words, the actual quality of these systems in playing the whole spectrum of the bass I would suggest is key to how authentic and impressive the bass sounds ...

Frank
 
Right now I found Pink Floyd channel on Pandora radio; listening to it. Some records definitely have content below 40 Hz: kick drum gives nice gut feeling. Even bass guitar that sounds above 40 Hz is soft and nice. Limit reproduction by 70 Hz, and this nice pleasant effects are lost.

It is not about notes. It is about such "pops" as kick drum, pipes, and so on that produce some LF and ILF content adding some realism.
 
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On the subject of classical music it depends a lot upon the era it comes from.

In the Baroque period the lowest instrument was generally the cello, the "double" bass being added towards the end of this if my memory serves.

Most of the early double basses were of the three string sort anyway that had a lowest note of a.

About this time the pedal board was introduced to the organ, this greatly increasing the power and extension of the bass.

It is true that there is generally not much bass power in classical music as perusal of the spectra of this shows, but in some instances there is quite a bit of extension and power in some movements, such as in the various late nineteenth century organ symphonies, and also the extensive use of percussion that became fashionable in the early twentieth.
As already commented on the sound of eight double basses in a live symphony concert is quite impressive and very difficult to reproduce accurately, the closest I have ever come is the combination of headphones and sub woofer.
rcw
 
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In my case, I listen to a lot of Blues since I was a child.... live, in concert and at home. But, I started out as a child at home listening to classical and still get to hear a lot of it. but bass is fundemental to the blues. I stopped counting after 10,000 blues tunes catalogged at my home. So the quality and quantity of the bass is important. Acoustic Double-bass in an orchestra need to be heard over the rest of the players and so have more of them as the symphony size gets larger. But still, there is a sense of weight to the music overall when they are playing with the rest. That weight or heft is missing if you cut the bass at 70Hz. It is noticable to people who know what the difference sounds like. High-Enders are expected to know the difference and strive for more, IMO.

I brought a High-End car into a car sound installer because that bass weight was missing. he heard the sound and said it was the best stock system he ever heard. Oh well. Never mind. Guess I'll go somewhere else.

The High-End isnt a popularity contest. You can cut the top octave and most people wouldnt care.... could cut it more and they might like it better. That isnt what High-End is about. Let's not make excuses for our systems short comings. None of the HiFi systems sound like real live musical instruments being played in my home, anyway. Set your sights high and strive to get it all.
Thx-RNM
 
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The High-End isnt a popularity contest. You can cut the top octave and most people wouldnt care.... could cut it more and they might like it better. That isnt what High-End is about. Let's not make excuses for our systems short comings. None of the HiFi systems sound like real live musical instruments being played in my home, anyway. Set your sights high and strive to get it all.
Thx-RNM
Yeah, the "high end" is where it's for me, as in the treble spectrum, ;). Hardest to get right, and the instant giveaway that the sound is not "real". Typically distorted, so either it's chopped off, muffled by judicious fiddling with cables and such like, or the simplest option: just don't play the music at realistic volumes

HiFi can't sound real, but optimised audio systems can. Again, the fundamental step is to believe it's possible and then steadily work towards the goal ...

Frank
 
'High end' for me is the effort to eliminate higher order distortions that can give listening fatigue, as well as to attempt to effect a 'you are there' at least for a moment experience with a lot of musical sources. For this, often 'inner details' in the music become apparent, and this can help to make it more realistic sounding. You know, when the applause actually sounds like hands clapping, rather than some sort of 'mush', or you get 'goosebumps' from the performance.
 
What are you saying, PMA? That LOW distortion is OK? Halcro was an esteemed competitor to Parasound, and many other hi fi manufacturers.
Now what did they do 'right' and what did they do 'wrong'?
They made elegant cases, that cost plenty to make and increased the cost to upper hi end, a little like the CTC Blowtorch.
They had VERY LOW measured distortion, probably the lowest in the industry. However it was almost completely derived by massive amounts of global and local negative feedback.
The actual circuit topology was derivative of other designs, and not the lowest open loop distortion topology possible.
The peak current was usually only 15A, a rather mid fi spec.
So you got to pay big money for something that had a pretty case, and no real effort in making the most sophisticated circuitry, but to measure the lowest in continuous 'sine wave' sort of testing.
What about listening? Many loved it, I found it OK, and some of my associates didn't like it. Kind of mixed. Now they are no more, and the rest of us hang in there.
It is a bad time to make expensive, exotic amps and preamps.
 
What are you saying, PMA? That LOW distortion is OK? ...
They had VERY LOW measured distortion, probably the lowest in the industry. However it was almost completely derived by massive amounts of global and local negative feedback.

Yes, low distortion is OK (I was under the impression that you designed for low distortion, was I mistaken?), and yes, apparently they knew what they were doing. Feedback works in the hands of someone who understands basic engineering- they even won "listening contests," so apparently the circuit was "sophisticated" enough. :D Rave reviews in Stereophile, since you seem to give that sort of thing credence.
 
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