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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 2:14 pm 
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jhulk wrote:
also it really is point less in having filter high than 16k as most of the oscillators in the scope range only have about 12khz range
you will notice this with filters where you have a filter set to 24khz that from about 3 oclock the sound does not change what i do is i listen to where the filter sound is constant with no change and find its start position then i set that as the top frequency in a control ranger and a start frequency of 20-30hz this allows when you have the knob at the bottom of travel you just get sub bass frequencies rather than no sound you will then get a full sweeping filter for the whole spectrum of your synth creation


This is more difficult with MIDI control (especially over knob assignment), but the new control ranger & 32bit control should be easy in BCModular!!

Good suggestion, Jamie.

The Control Ranger stuff is great for emulating other circuits & synths, too ;)


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 2:21 pm 
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come on guys what i'm talking is the common sense.
You can't re-invent lost information.
Going from a higher sample/bit rate to a lower is possible because you just delete info.

Oversampling is used so to allow modules inside the signal chain to work with higher sample rate.
You pad zeros to get a higher word length from a lower one and interpolate to get more samples.

When you decimate you actually do a sample and hold driven by an oscillator at the specified frequency.
When you record or sample any signal you really sample and hold it.

When you bit crush, you delete bit-rate information on purpose.

Both techniques are very important when simulating analogue devices.

I think the discussion here is that in some cases the "grit" of lower sampling or/and bit rate is considered a nice quality sound-wise
and someone said it can't be reproduced equally. I say it can.


Last edited by fra77x on Thu Jan 22, 2015 2:55 pm, edited 1 time in total.

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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 2:39 pm 
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also people need to learn about sample theorem

the reason for the 44.1 khz standard professional rate is it camptures the whole frequency range of 20hz-22.5khz

our hearing is 20hz-20khz

now that range is for a whole performance of a song that has many instruments in different frequency ranges

you need to understand that a 80hz bass has usually a frequency content of 20-85hz max nyquist states to capture a full spectrum of the bass sound we need to record it at double its sample frequency in this case sampling it at 170hz would capture it so sampling it a 44.1 is not going to capture any more of the sound than sampling it a 16khz the only thing your going to capture is the noise from the dacs and outputs

no point in sampling korg 01w at 24bits 96khz when its brick wall filter is set to 16khz or even its samples are recorded at 8 bit compressed 3150hz format if you record these at 32khz you will capture all the sound that the korg kicks out

1 recording at 24bit 96khz is a waste of memory
2 it will not sound any better than the 32khz 16bit range of the outputs

i sample first i choose a sound then i play its range through a analyzer to see its max frequency playback then i double it and find the nearest rate that allows me to sample it at

i use apogee and focusrite and protools convertors and scope but use cool edit pro 2.1 and set it to sample at any frequency playback rates that my samplers can play back at

that way i capture the best sound picture i can with the best available ram and size and loop

i try always to sample with out loops for transient sounds for long sustained sounds that evolve i always sample a minimum of 8 seconds per sample and if its a long transwave or wavesequencing i sample them until they loop correctly

when doing piano i sample at 30-40 seconds then crop the samples as they get smaller its really hard to loop piano because of its stretched tuning they might start of as say c1 but change pitch over time when looped the loop is out of tune to the sample

now i started with mirage and EII and we only had 64k on the mirage and 400k on the eII by using variable sample rates we could get more samples in this would mean sampling at the frequency for that note root key

with kontakt today they just sample at massive rates and bit depth hans zimmer actually liked using sampled strings with real strings with his multi roland s760 samplers he had a switcher which swapped a moniter to the outputs of the s760 and he could have 4 s760 with one switcher which allowed one mouse and 1 screen for editing all of them

some of the best sounding romplers come from the mighty 12bit k250 the range was k1000 series they have brick wall filters ranging from 10khz-12.5khz as there samples never had frequency content above that and they sound great

most of the samples were done at 22.5khz and used ulaw 12bit dacs this allows a 16bit sample to be compressed as a 8bit wave and compounded to 12bits via the u-law dac same as what is used in the EII but a-law 8bits

the a-law/u-law 12bit dacs have been emulated by aly james he recreated the dac in c++ for his linn drum emulation now fra77z if we could port that as a module with rom reading then a true rendition of 12bits can be acheived


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 2:50 pm 
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Look i don't use romplers at all.
Of course for hardware with limited memory sampling at higher rates is wasteful.
You can achieve good results with lower rates.
But to fully capture the spectrum a human hears for the whole range of common instruments a bandwidth of 44100 is required.
That is basic.
I don't have any problem with media using lower sampling rate or bit length.
The output of the casio sk-1 as i read is 9.35 kHz and 8 bit.
I don't care if it is low by the current standards if it satisfied people in it's time and can still do it occasionally.
I don't have any problem with your method to create multi-samples and so on. I just never ever do it.
Also i don't have problem with dull music. Just to be good. :D

My point is that with dsp techniques applied on a system with higher rate you can match any result created on another system
with lower rates.


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 3:19 pm 
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i have to do it as i still use the hardware

so my myriads of sampling hardware i use to get that sound that produced those records of the 80,s and 90,s

we make commercial dance and techno drum and bass and rave and hard house and house is kicking again in a big way i was producing this in the late 80,s and 90,s so to get that sound i use the hard ware i used back then to produce the original sounds and samplers where the key

so i use the techniques i aquired back then to get the sample i require to use with the constraints of the memory it makes you a better programmer i also use hardware sequencers as much as i can before committing it to the daw which i find can really slow the production process down due to its overbloated features and gui bliss that dazzles you rather than inspires you

i still use a atari st for midi a lot sequencing on that then recording the audio in the daw atari st timing in midi is second to none and the mpc60 is just great

i use scope as another tool to get me what i want i make modular synths in scope to get sounds i cant from my other gear
all are tools for our ideas if i want that 12bit sound ill use my

EII /epsm/dsm1/dss1/akais950/s330/w30 dont see the point in emulating it as i can by a w30 for £50 and get that sound or s330

which is a d50 with out rom


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 3:31 pm 
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I know you are the best in wave-table synthesis and i admire you for that.
It's best to use what makes one comfortable. I haven't said a single word against lower sample or bit rates.

I said one simple thing. (i won't say it again).

I made a small graph about up-sampling.

Attachment:
upsampling.jpg
upsampling.jpg [ 145.71 KiB | Viewed 1467 times ]


Also you may found interesting that article http://en.wikipedia.org/wiki/Ringing_artifacts


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 22, 2015 4:22 pm 
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This thread has great information.

Thanks for showing the shortcomings of upsampling, it's true, and unfortunate at the same time. And probably points out my "desire" for various modules to run at various rates, was really a desire to have the best of each module has to offer (running filters at higher rates, etc)....but even then there are negatives.


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 2:05 am 
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i totally agree with you about the upsampling fra77z

i never disputed that

and why i always down sample

many designers have tried to get the 12bit sound ni have a s950 and sp1200 sound 12bit emulation but it does not sound the same

when comparing

the problem is its not just the dacs but all the components used crosstalk temp that can change the sounds

the problem with dsp is unless you model each component and create exact circuit emulations you are not going to get the sound


as for me the sts osc can play 16bit samples well and at any frequency playback rate that the sample was saved at if you want grunge sample at 8bits save as 16bits linear and you will have 8 bits data in a 16bit file padded by 0

so for a full 256 8bit sample it would be 11111111 in a padded 16bit file it would be 1111111100000000 same data this would be for a single cycle period of a sound now the frequency rate would be frequency range by seconds so for a 12khz sample for 1 second x 8bits would give you 12000 8 bit results for one second of sound

as there was never a 12bit program for saving as a 12bit audio file it was actually done in 16bits on a mac and sd2 and then dumped to the sds12bit standard unless you recorded via the 12 bic adc

when you convert a emax or eii 12bit file you always get a 16bit file 12bit dat padded by zeros

so a full 4096 sample 111111111111 and a 16bit version would be 1111111111110000 still 12bits data in a 16bit file

if you want a 12bit sound just do bit reduction this will add distortion but many people call it crunch and on high frequency sounds like the snares and hats the lower the frequency rates the less smooth the sample calculations between the points

now the problem with looking at waveforms on a computer is they look steppy but they are not its just how they are represented in the computer as lots of tests were done with these steppy waves from a computer when rendered to analog by the dac on shown on a scope there was no steps in the waveform

up sampling does cause ringing but that ringing is usually brickwall filtered out


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 2:15 am 
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frazz7 if you want some 12bit samples recorded i can record from several devices for you if you want the challenge of replicating the sound with the sdk

yes it can be done do you want me to record at all frequency settings and resonance so that you have a chance to get all coefficients of the sampler as its not just the dacs but the filter also that makes the digital samples into analog warmth

that would be 128 frequency setting recordings per resonant setting

that would give you an accurate picture of what happens

ill can use a saw single cycle made by the additive engine this would give a good spectrum of frequency range of harmonics

and at the full frequency range of the filter with no resonance would give you the 12bit dac sound


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 3:32 am 
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I would prefer just one sample. A riff or something that has the qualities you mention.
One that you like and makes you say, i could use that in a tune and i can only make it with that specific
hardware due to it's limited sample/bit rate.
Information about the sample/bit rate of the hardware would be nice and the midi track.
Perhaps the oscillator type.


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 4:35 am 
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things to consider (as already mentioned by jhulk):
the analog response of the device - input and output
cross-influences based on (flaws of) circuitry
the original math of the device - a 'vintage' CPU is way different from modern versions
(artifacts are in the nature of digital processing for the continous-discrete paradigm)
programming style: developers in the 'early days' were used to machine code
(this results in a much more individual style than todays library approach)

an EMU EMax (or similiar) would be a valid option for a project
a Casio SK-1 is so full of irregularities, that it would end in a key-by-key programming approch
(a ridiculous amount of effort for a $20-50 'toy')
these things just happened because a kind of (cheap) technology was available
I don't think anyone bothered about comparison to 'real' samplers of the time
it's a matter of chance that offers one additional color on the acoustic palette - no more, no less
(imho) the sound is quite useful as a source because of it's rich non-linear spectrum
gives the filters some more to chew on - and will work great if a little polished by reverb
(on most Casios you hardly can tell the source by listening to them in a mix - except the famous rhythm bleep)

cheers, Tom


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 5:19 am 
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the fz1 was the first sampler to be 16bits first sampler to use a hd floppy

and the first to use a digitally controlled analog filter core the sound output from the filter is analog but the frequency and resonance control was digital

8 stage envelopes great for looping

and was one of my used samplers in the hardcore rave days i still use it and have 1000 floppy disks of sounds that i used

its a great sounding sampler and it still sells well on the second hand market

but again its a tool for creating sounds its another synth like the dss1 with an additive engine

i converted the whole fz1 library to sf2 if any one wants it as its public domain samples they are license free


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 5:41 am 
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that's another good example of 'sound quality by specific programming'
I still have the rack version FZ10 (?) in hibernation (dark display...)
but I remember a particular guitar sample set as one of the most 'musical' of that kind ever
maybe I'll set up a DOS machine one day to revitalize the stored library with a parallel port adapter
(there was a DIY instruction on the net ...)

cheers, Tom


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Fri Jan 23, 2015 9:40 am 
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My mother has a sewing machine unrepeatable.
The engineer who built it chanted three spells and made two sacrifices for each component used

Where is the sample?

:lol:


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 29, 2015 11:52 am 
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i got round to sampling some sounds from my kurzweil k250
when im back at the bristol studio ill sample the korg dss1 and the akai s950 eII emax1

i sampled them in 44.1khz stereo i did a few sounds and did every c note from c1 to c6 this is the 12bit dac sound of this instrument they dont have any filters at all apart from brick wall filters this was a bob moog and ray kurzweil design and is still one of the nicest sounding samplers still

https://www.dropbox.com/s/8791rq4did5ho ... s.zip?dl=0

if you could make a module that mimics the frequency response of the 12bit dacs and the opamps from these sounds would be cool

i also have a sp1200 and 12bit s330/550 which i can also sample it would be good to have dsp processing modules for each type

thanks more samples to follow


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 29, 2015 2:03 pm 
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Hi,

The 10-bit samples on the kurzweil or 12-bit playback system of it, just reduces the dynamic range.
The signal to quantization noise ratio.

You can notice the difference only when trying to sample sounds with great dynamic range
like a sound that has loud and quiet passages. For simple samples there is no difference at all.

http://en.wikipedia.org/wiki/Audio_bit_depth
"The bit depth has no impact on the frequency response, which is constrained by the sample rate."

http://en.wikipedia.org/wiki/Quantizati ... cessing%29

The attached wave file presents a 16-bit, a 12-bit and 10-bit piano sample.
I had to change the volume of the sample for each recording so to compensate for the additional gain the bit reducer introduced.

You can listen to the quantization noise if you listen carefully to the 3rd sample (10-bit) at the tail of the piano note.

Attachment:
bit rate reduction.zip [1.24 MiB]
Downloaded 28 times


So in that case you simple like the samples included in the Kurzweil K250 and of course the specific algorithms used (for effects etc).

Regards


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 29, 2015 3:34 pm 
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no fx on the k250

sn ratio is lower for lower bit depths because of the calculation in the max numbers it can compute

obviously thats the k250 sample

the other 12bit machines use different dacs and filters so its not just the 12bit sound but also the synth parts

which act on the sound if you think you can create that sound via the sdk of that samplers output

as a lot of people are looking for that sound with out the £xxxx price tag

and why the second hand market is rising for these machines


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 29, 2015 3:36 pm 
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also the k250 is a sampler so i can sample sounds in sd2 and dump them via the special software that the kurzweil uses to analize the samples to create sound files


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 Post subject: Re: scope waldorf oscillator now in hardware modular module
PostPosted: Thu Jan 29, 2015 4:49 pm 
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Don't bother forget it. For me there is nothing particularly interesting about these keyboards.

I have created a piano sampler for my daw application. Everything works in 96kHz 32 bit.
96 notes polyphony without voice assignment for about 10% of my laptop i5 processor.
I can route different instances/channels to different asio outputs in scope for mixing-production.
It fulfills perfectly my needs.

These days i use only 3 pieces of equipment: my daw/sampler/modular designed in c, wavelab (i'm gonna replace it with my own app),
Scope sdk. I enjoy simplicity and peace of mind. :)


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