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Old 18th June 2004, 01:16 PM   #1
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Default anti digitalizing process

my friend has a digital multi effect for his guitar.
its output sound sucks.
if i put a tube preamp between multi effect and guitar amp, will it sound better?
im lookin for a more...analog...smooth...sound.
is it possible?

thx in advance
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Old 18th June 2004, 03:00 PM   #2
benny is offline benny  Australia
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you will never get rid of the digital sound which is probably why the output sound sucks... no matter how many tubes you use. even analogue modeling pedals still sound digital for the very reason of there being a DAC to convert analogue into digital, and then back again... problem is, even the most expensice DAC's still can;t avoid that digital sound... what's in your friends effects is probably far from expensive, and therefore, sounds very digital...

to think of one major problem of digital, think of sampling and bit rates, effecting frequency and dynamic range... sound is altered hugely here, and you loose a lot of quality... like comparing a digital photo to a photo on film... you still make out the same image, but the one on film retains much more detail.. both colour depth and image quality, whereas a digital shot pixilates and looses a lot of colour depth.


Quote:
if i put a tube preamp between multi effect and guitar amp, will it sound better?
yes, as long as it's a good preamp, and you're not driving it into clipping while you're meant to be playing clean undistorted sounds, then you will warm the sound up if the preamp is designed for this...

Quote:
im lookin for a more...analog...smooth...sound.
can you get;

analogue? --> no

smooth --> more than before, but you will still hear that digital sound...
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Old 18th June 2004, 04:20 PM   #3
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Sorry Benny, that's complete bullsh1t. You're not providing any figures to back up your statements, just a load of handwaving.

Please tell us how the ADC process affects dynamic range and frequency response, considering that there are plenty of DACs and ADCs that will do 120dB dynamic range without problems, and with a frequency response flat to 90kHz (192kHz sampling).

As for digital photography, you should check out a proper camera, not a £10 webcam. The gamut of a decent CCD easily comparable to film stock, and with resolutions of 10mega pixels and up, the resolution is on par with 35mm.

Fair enough, someone may have a preference for analogue sound (I should know, I have two superb tube monoblocks in my hi-fi), but please don't try to tell us about technical benefits that just don't exist. m'kay?
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Old 19th June 2004, 06:57 PM   #4
benny is offline benny  Australia
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Quote:
what's in your friends effects is probably far from expensive, and therefore, sounds very digital...
i made this statement and discussed digital in respect to this consideration...

i am predicting this guys dac is far from 90kHz considering it's in guitar effects, which for the most part use cheap parts because the manufacturers know they're not making audio equipment that is going to be judged by discerning audio engineers and the likes... more likely just your average guitarist who's playing through some 30W practice amp and wants something to colour their sound a bit more...

i'm predicting a sampling rate closer to 30kHz.. i looked up the manual for an amp modeler i have, and despite having a bit rate of 24bits, it has a 'sampling rate' of 31.25 kHz... i don't know what frequncy response this gives, but i'm guessing it's not terribly good... and think of this like putting together a puzzle... so many times a seccond, you're dac takes a snapshot of that time period, but it must join the pieces together... i doubt there is a 'perfect' dac that can do this 100% error free... some can probably do it better than others, and this is probably why you can pay more for another dac with the same bit and sampling rates... because one does it's job better than the other...

Quote:
As for digital photography, you should check out a proper camera, not a £10 webcam. The gamut of a decent CCD easily comparable to film stock, and with resolutions of 10mega pixels and up, the resolution is on par with 35mm.
hate to tell you that this is complete bullsh1t... the fact that you can put a pixel value on it shows you've already lost quality compared with 35mm which has an almost infinite resolution (up to a limit, then the image looses sharpness, but this is only when blown up to be HUGE... like say with dimensions comparable to a 747 plane)

As far as checking out propper cameras, i'm guessing that the fact that as a media student who's using digital cameras worth close to 10 grand each that use 3 of those decent CCD's you talk about per camera (comonly known as 3CCD) that i dont have any idea do i??? resolution aside, and without talking about other things that ocour in motion cameras such as interlacing and what not, you still loose a lot of colour quality. Even HDTV format does not compare with film. we can even start to discuss motion, as capturing sound is like capturing motion... even though these cameras shoot in 'frame' mode, which is similar to film in that unlike most digital cameras they do not interlace frames, the motion still never compares to film... even after using something like FilmFX which is a digital film simulator, it still dont compare if you look closely... it comes close, but still not quite.

if i somehow implied all digital is bad, i didn't mean this.. i was discussing digital in repect to his friends effects... so maybe comparing 10 pound web cams with more expensive ones is a fair analogy to make in this case.

cheers
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Old 19th June 2004, 07:37 PM   #5
EC8010 is offline EC8010  United Kingdom
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Default Unfortunate analogy

Gentlemen, I'm afraid that comparing digital and analogue audio with 35mm film and CCD cameras is an unfortunate analogy. Sony would have you believe that their best cameras equal the performance of 35mm film - of course they would, broadcast budgets have fallen through the floor, whereas the film industry can afford to spend far more money on cameras. However, the CCD vs 35mm issue is hotly contested, with the film supportors pointing out that film has an S-shaped transfer characteristic (giving gentle compression at the top and bottom of the range), and that film grain is random, whereas CCD sampling is fixed. Conversely, the CCD supportors point out that video uses cheap re-useable stock. The debate rages back and forth...

Regarding stills cameras, I have a Nikon F4 (35mm body) and a Nikon D100 (digital body). Admittedly, the D100 isn't the best digital body on offer, but it's not bad. Using the D100 confirms my broadcast experience - exposure is hugely critical compared to film, and I wouldn't dare have a poster sized print made.

Having strayed dangerously off-topic, where does this leave us regarding digital musical effects?

ADC and DAC manufacturers claiming 120dB dynamic range habitually apply "A" weighting to their noise-shaping convertors to obtain such a nice number. I would imagine that different guitars produce different outputs, but the effects pedal needs to be able to cope with all of them without clipping. That means that the quieter guitars must be much closer to the digital noise floor of the convertors. Further, I'd be very surprised if digital effects pedals have beautifully low jitter clocks and correctly applied dither.

To sum up, the principles of A/D conversion and DSP are fine, but the implementation is often flawed, especially in "price sensitive" markets.
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Old 20th June 2004, 09:04 AM   #6
sreten is offline sreten  United Kingdom
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Default Re: anti digitalizing process

Quote:
Originally posted by electro samurai
my friend has a digital multi effect for his guitar.
its output sound sucks.
if i put a tube preamp between multi effect and guitar amp, will it sound better?
im lookin for a more...analog...smooth...sound.
is it possible?

thx in advance
The best option is to arrange the multieffects to be in a
send return loop of the amplifier so it is working at line
level rather the low guitar input levels.

sreten.
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Old 20th June 2004, 10:24 AM   #7
benny is offline benny  Australia
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Quote:
However, the CCD vs 35mm issue is hotly contested, with the film supportors pointing out that film has an S-shaped transfer characteristic (giving gentle compression at the top and bottom of the range), and that film grain is random, whereas CCD sampling is fixed
maybe another not so good analogy... i think using this would be more like something you'd use in an analogy comparing tube and solid state audio clipping... not really relating to conversions because this is talking more about colour added to the image your analogy, not how much of the image is actualy recorded... this is one of the beautiful things about film, just like tubes, the colour they add makes them nicer to look/listen too... there is also the whole side of films ability to capture far more information, which is closer to what i was trying to get a cross... for example, go and point a digital (motion, not still) camera at a whole lot of green leaves on a bush being blown by a strong wind, and then point a film camera, and see which one records it better... the digital camera has trouble recording this as well as film, because it's trying to record an infinite amount of information and put a finite limit on it...

but anyway... all of our not so good analogies aside, i only bought up the digital photography thing becuase it is another case of trying to convert waves (this time light) into a whole lot of 1's and 0's... and the amount of data that can be stored, and the integrity of this data is inherently limited because of digital trying to record and almost 'infinte' thing as something finite...

of course, there is the cases of high quality equipment, but a digital guitar effect is generally not going to have the best dac unless you go using something more up market like one of the G-Force units, but i can't see many people justifying the big money to buy one of these unless they're an absolutely serious musician as their job.... can't see anyone who's not a muso by trade, or a very rich hobyist forking for something like that... this is where i was coming from.

Quote:
To sum up, the principles of A/D conversion and DSP are fine, but the implementation is often flawed, especially in "price sensitive" markets.
exactly... if a good quality DAC is used, while it's still not going to retain all of the original signals quality, it will probably retain more than what the average human ear can discern.

cheers
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Old 20th June 2004, 08:51 PM   #8
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Quote:
Originally posted by benny


maybe another not so good analogy... i think using this would be more like something you'd use in an analogy comparing tube and solid state audio clipping... not really relating to conversions because this is talking more about colour added to the image your analogy, not how much of the image is actualy recorded... this is one of the beautiful things about film, just like tubes, the colour they add makes them nicer to look/listen too...


Exactly my point! It's not that digital has inferior specs in any way to analogue, but that it doesn't add pleasant alterations to the signal...

Quote:
there is also the whole side of films ability to capture far more information, which is closer to what i was trying to get a cross...
Nooooooooo. Depends on the film stock... an ISO 50 film is going to have much lower grain than an ISO800 stock. They have different uses, ISO50 would be excellent for portraits in a studio, but useless for night shots or sports photography.
If fillm had infinite detail, we'd be using super 8 for IMAX presentations.

Quote:
for example, go and point a digital (motion, not still) camera at a whole lot of green leaves on a bush being blown by a strong wind, and then point a film camera, and see which one records it better... the digital camera has trouble recording this as well as film, because it's trying to record an infinite amount of information and put a finite limit on it...
Are you saying that a film camera will record an infinite amount of information? Maybe we've stumbled across a new law of physics

Quote:
but anyway... all of our not so good analogies aside, i only bought up the digital photography thing becuase it is another case of trying to convert waves (this time light) into a whole lot of 1's and 0's... and the amount of data that can be stored, and the integrity of this data is inherently limited because of digital trying to record and almost 'infinte' thing as something finite...
Try recording a bullet flying through the air with a 24fps film camera, best quality film you can get. If your theory is correct, you will have a copy of every nanosecond of the exact flightpath of the bullet, in infinite resolution (down to the atomic level at least). If you can't record it, then you are losing information i.e. you have a FINITE level of detail.

Quote:
of course, there is the cases of high quality equipment, but a digital guitar effect is generally not going to have the best dac unless you go using something more up market like one of the
And again, you could say the the average Joe is going to be using a compact 35mm camera, with cheap plastic lenses.


Quote:
G-Force units, but i can't see many people justifying the big money to buy one of these unless they're an absolutely serious musician as their job.... can't see anyone who's not a muso by trade, or a very rich hobyist forking for something like that... this is where i was coming from.
exactly... if a good quality DAC is used, while it's still not going to retain all of the original signals quality, it will probably retain more than what the average human ear can discern.

cheers
At last, I think we can agree on something here. There is no such thing as being able to record an infinite amount of information... you're always going to lose something, whether it's in the temoral domain (things happening in between the frames of a film), or in the detail you capture in each frame.
The best we can hope for is to capture enough to fool the human eye/ear into believing what it detects is a good approximation to the real world.

Arnie
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Old 22nd June 2004, 03:27 PM   #9
benny is offline benny  Australia
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Quote:
Exactly my point! It's not that digital has inferior specs in any way to analogue, but that it doesn't add pleasant alterations to the signal...
it also adds unpleasant alterations... not so important for guitar, but in hifi where every bit of distortion counts, AD/DA conversion contributes a fair bit to the total system distortion... but then again, i guess the needle on a record player also contributes to distortion, which comes back to that same thing of 'nice' colourations.... probably why a well cut record sounds far better than CD.

[QUOTE]Nooooooooo. Depends on the film stock... an ISO 50 film is going to have much lower grain than an ISO800 stock. They have different uses, ISO50 would be excellent for portraits in a studio, but useless for night shots or sports photography.
If fillm had infinite detail, we'd be using super 8 for IMAX presentations.[QUOTE]

yes, true... i already pointed out the size restrictions of the detail thing in my second post though... although what you say about ISO is very valid... it's kinda like sampling rates almost... ISO baisically relates to the speed of the film... how fast it can record light... just like sampling rates are how fast it can record sound.

Quote:
Are you saying that a film camera will record an infinite amount of information? Maybe we've stumbled across a new law of physics
yes... 'frame information'... not every single minute detail down to every atom... just as our eyes are limited in the detail they can see by how close we are... the further back we are, the detail we see... so is any camera... how we use zoom/focus/apateure and where we put the camera in relation to the subject, it will affect what it 'sees', but it will record all of the information for that frame... just like when we blink, we don't see for a little while, so must a camera 'blink', and will miss information then...

also comes down to the film size and what it 'sees'... 8mm, 16mm, 35mm, 70mm... this relates to the size of the 'projected' image... the more surface area of the recording medium, the more detail it will 'see' because a larger image can be projected onto it. a better analogy would be to compare the detail of say 35mm film, and then compare this to the detail of an equivalent size CCD... becasue the CCD must 'pixilate' this information, it is loosing information between pixels, despite seeing the same image.



Quote:
Try recording a bullet flying through the air with a 24fps film camera, best quality film you can get. If your theory is correct, you will have a copy of every nanosecond of the exact flightpath of the bullet, in infinite resolution (down to the atomic level at least). If you can't record it, then you are losing information i.e. you have a FINITE level of detail.
again, comes down to what is being 'seen'... what a film camera can see is exactly the same as what a digital camera will see presuming it is essentially the same camera, same lens, etc... only difference is how they record the information... one is more effective that the other as far as detail... the other is just more cost effective.

trying to record a bullet is limited because the problem of light... it would be possible with the right set up though... even with the 24fps, it would still be possible to record a blured image of it, but there comes the problem of trying to have a slow enough shutter speed to actually alow the camera the chance to record one frame where the bullet is in frame... and also being able to set the correct apaeture while still being able to record enough light to pick up the bullet as it wizzes by, while not saturating with other environmental light...



Quote:
And again, you could say the the average Joe is going to be using a compact 35mm camera, with cheap plastic lenses.
go and compare that camera with an equivalent priced digital... you might find that the film camera is a little higher quality...


Quote:
At last, I think we can agree on something here
maybe not a case of disagreement, maybe we're just misinterpereting... i know i haven't explained myself exactly how i meant all the time... but anyway, i think we're getting to the point of 'limitations' in what can be recorded by different mediums... and this is always going to be an issue as we will always be trying to put that finite limit of what we record.

cheers
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