ben m
Joined: 15 Sep 2002
Posts: 344
Location: UK |
| Week 6 - Sampling 1 |
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Ok, new topic this week, 'Sampling'. Should be a bit easier than the last couple of weeks synthesis questions!
01- What are the logistical disadvantages of multisampling?
02- What is the importance of 'zero crossing' with sampled material?
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
04 - What are the benefits of multisampling?
05 - What are the advantages of USB connectivity for a sampler?
06 - Why do some samplers offer SCSI connectivity?
07 - What is 'tracking'?
08 - Why might an LFO be used with a sample?
09 - What filters are commonly offered with contemporary samplers?
10 - How do 'soft samplers' such as Gigasampler store their samples?
11 - Why are Zip Drives used with some hardware samplers?
12 - How can a sampler be used to add a 'vinyl effect' to a song?
13 - What benefits do samplers with multiple physical outputs have?
14 - What are the benefits of working with mono samples over stereo samples?
15 - What MIDI control messages can a typical sampler read?
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using a sampler?
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
18 - How does a hardware sampler ensure that there is no latency?
19 - How can sample looping be used to save storage space?
20 - What are the main requirements of a glitch free loop?
21 - Why are closed and open hi-hats often sent to the same mute group?
22 - On hardware samplers, how much sampletime would you typically get out of 64MB storage?
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
24 - How might you soften the start of a drum sample (single hit)?
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a sample? |
Mon Apr 11, 2005 12:12 pm |
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JohnA
Joined: 20 Jan 2005
Posts: 28
Location: Mid Glamorgan, UK |
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Audio Course
AUMT03
Week 6
SAMPLING 1
JohnA (mixindown)
01- What are the logistical disadvantages of multisampling?
Multisampling is sampling a sound, for example, an acoustic piano, at various points along its frequency range (different keys) to accurately capture the sound. This is both time consuming and requires a lot more storage space for the recorded samples. Usually samples are taken and, when a different pitch is required, the key is transposed. However, multisampling is necessary when trying to represent an accurate replication of an acoustic instrument.
02- What is the importance of 'zero crossing' with sampled material?
If you have created a loop with a sample, you must make sure that the beginning and the end of the loop match up in level, shape and phase. If these levels are not matched up, it is likely you will hear a glitch in the sound.
Clicks can be minimized by looping at 'zero-crossing' points (the point where the electrical signal crosses over from being positive to negative or vice versa), but if the waveform levels and shapes don't match pretty closely, you may still hear a glitch.
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
If a vinyl record is warped, it will not play back at the correct pitch and so the sampler will not be able to sample the original recording accurately. Also, the motor and belt that drive the turntable on the record player could play at varying speeds which would affect the pitch/tempo of the end sample.
04 - What are the benefits of multisampling?
Many sounds can become unnatural sounding when transposed far from their original pitch. This can make it difficult for faithfully reproduce the sound of, say, an acoustic piano by transposing a single sample over the keyboard. The sound can be lost by moving just a few semitones either side of the original sampled frequency. The only way around this is to sample the original instrument at different pitches (frequencies) and use each of these samples over a limited part of the keyboard controller (the areas where the keyboard covers a specific sample are called “”keygroups”). So by multisampling, you create a more accurate representation of the original sound.
05 - What are the advantages of USB connectivity for a sampler?
If a sampler has USB connectivity, it will allow the sampler to be connected to a large number of computers so that you can send information to / from the sampler / computer. The computers hard drive can then be used to store / load samples to and from the sampler. Also some samplers use USB host and slave support. The host support allows direct connection of USB storage devices such as USB floppy drives, CD-R drives, external hard drives, ZIP or MO drives, USB keyboard connection. USB slave connection allows Network Systems, providing complete program editing, multi editing and file management.
06 - Why do some samplers offer SCSI connectivity?
Some samplers offer SCSI connectivity to allow you to be able to connect a SCSI hard drive. You can then store samples on the drive. You can also transfer samples from your sampler to your PC if your PC has SCSI connectivity. SCSI connection also allows you to connect a CD ROM drive to the sampler, enabling you to load pre-recorded samples into your sampler.
07 - What is 'tracking'?
Tracking is when the cut off frequencies of a filters are increased along with the frequencies of the note in order to make the sound a more realistic.
08 - Why might an LFO be used with a sample?
Using an LFO with a sample enables you to be able to alter the modulation of the sample.
09 - What filters are commonly offered with contemporary samplers?
Filters that are commonly offered with contemporary samplers are HPF (High Pass Filters), LPF (Low Pass Filters) and BPF (Band Pass Filters).
10 - How do 'soft samplers' such as Gigasampler store their samples?
The samples in a soft sampler are stored on the hard drive of the computer.
11 - Why are Zip Drives used with some hardware samplers?
In the early days of sampling, hard disk drives were extremely noisy and very unreliable. Zip drives on the other hand, enable you to record onto an external cartridge. These drives are much quieter than the standard HDD and the cost of the disks was quite low. Also, you could easily make a number of back up copies of your samples (just in case your HDD failed).
12 - How can a sampler be used to add a 'vinyl effect' to a song?
A sample of white or pink noise could be sampled and added to the song.
13 - What benefits do samplers with multiple physical outputs have?
Samplers that have multiple outputs enable you to send different samples to different inputs on a mixing desk. These samples can then be treated with effects such as reverb, chorus, etc. Also, these outputs could be connected directly to a computer of multitrack recorder for recording the samples.
14 - What are the benefits of working with mono samples over stereo samples?
If you use the full audio bandwidth of 20kHz using a sample rate of 44.1kHz, one minute of stereo sound will take up around 10Mb of RAM. If you sample this in mono, you, it cuts the used RAM down to half (5Mb in this case) so you immediately double the sampling time available to you.
Also, when looping samples, it can be difficult to get a good waveform match in stereo. You may have a good match on one channel but not so good on the other. Here, sampling in mono eliminates this matching problem.
15 - What MIDI control messages can a typical sampler read?
A typical sampler can read Note On/Off messages, Bank Select and Program Change messages.
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using a sampler?
You could “loop” the sample that you have recorded. Take a sample of a note from a flute. Once the initial attack time of the sound has decayed, the sound stays pretty constant in the sustain phase. You can sample the first few seconds. Then loop this middle sustained section. Now, when you press the key on the controller you are using to trigger the sample, it will run through the sound from the beginning to end, then return to the loop section and constantly play that loop until you release the key. To make the loop react smoothly, its worth making sure that the beginning and the end of the loop match up in level, shape and phase. This is one of the main reasons you get “clicks” and “pops” in sampled sounds. Sometimes, compressing the sound can make it easier to loop samples, it helps keep the levels more consistant, but having a short crossfade is a better solution.
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
SCSI, Digital In / Out, Analogue In/Out, AES / EBU / S/PDIF In / Out, Stereo Mix Outputs.
18 - How does a hardware sampler ensure that there is no latency?
The samples in a hardware sampler are loaded into RAM. When played back from RAM, there is no latency.
19 - How can sample looping be used to save storage space?
A loop is a small section of a sample that is played over and over again. Using a loop means that you don’t have to keep making samples of the same sound, which you would have to store each time you made the sample.
20 - What are the main requirements of a glitch free loop?
The main requirements of a glitch free loop are to ensure that the start and finish of the looped section are equal in level, shape and phase.
21 - Why are closed and open hi-hats often sent to the same mute group?
Open and closed hi-hats are played at different times. When you send them to the same group, only one will play at a time.
22 - On hardware samplers, how much sampletime would you typically get out of 64MB storage?
A mono sample lasting one minute will need around 5Mb or RAM at 44.1kHz. So 64Mb/5Mb = 12.8 minutes in mono. And 6.4 minutes in stereo. So approximately 13 minutes in mono and 6 ½ minutes in stereo.
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
If you use two samples and apply an LFO to one of the samples, you can set the LFO to modulate “out of time” with the first sample, creating a chorus effect.
24 - How might you soften the start of a drum sample (single hit)?
This could be achieved by applying a small amount of attack to the ADSR envelope.
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a sample?
In the sustain phase.
John A
http://www.soundonsound.com/sos/1996_articles/jan96/samplebasics1.html
http://www.soundsonline.com/whatis.shtml
http://www.millennium-music.co.uk/home/products.pl?ProductCode=AKAZ8&mode=detail&subcategory_id=SAMPLERS
http://www.samplecraze.com/tutorial.php?xTutorialID=8 |
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Wed Apr 13, 2005 2:08 pm |
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rachelh
Joined: 16 Jan 2005
Posts: 35
Location: Trinidad WI |
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01- What are the logistical disadvantages of multisampling?
The logistical disadvantages of multisampling are firstly because of the many samples are needed to match the original instrument that is in realistic terms- which can prove to be tedious, secondly, due to the sensitivity of the human air, a next to perfect match has to be achieved as the listener will innately sense the limitations of the sound and know that something is wrong and thirdly, multisampling takes up a lot of memory due to the many samples that are needed to achieve a good match.
02- what is the importance of 'zero crossing' with sampled material?
The importance of ‘zero crossing’ with sampled material is that it allows the smooth transition between sampled clips as their cross over points are at the same level [they are the same] thus they flow seamlessly, eliminating popping and ticking which may occur out of a less than seamless transition.
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
Problems that may arise with sampled material from vinyl in terms of pitch/ tempo are inconsistencies in the tempo and pitch due to either the condition of the record and the record player. Warping occurs when records are poorly stored, this leads to pitch and tempo fluctuations. If the record player has problems with the reading head or any of the apparatus used during playback, this will affect the pitch and tempo of the sound.
04 - What are the benefits of multisampling?
The benefits of multisampling are that if the samples used create a good match to the original instrument, the result would be sonically pleasing to the air thus creating a good mix, secondly, it allows for creativity and better understanding of instruments and their envelopes.
05 - What are the advantages of USB connectivity for a sampler?
The advantages of USB [Universal Serial Bus] connectivity for a sampler is that it allows for USB devices such as Zip drives, USB MIDI’s, and other associated devices to be directly connected to the sampler also, it allows for the sampler to be easily connected to a computer via the USB port [via a USB MIDI connector].
06 - Why do some samplers offer SCSI connectivity?
SCSI [Small Computer Systems Interface] connectivity / SCSI Sample Dump Formats are offered in some samplers because of the rate of data transfer associated with SCSI is faster than that associated with MIDI [Musician Instrument Digital Interface] Lines/ [MIDI Sample Dump Standard –SDS]. Samplers that communicate via MIDI lines tend to be very slow; data is transferred at a rate of 32.25 kbaud whilst SCSI has a transfer rate of 16 Mbytes/ sec or higher. SMDI – SCSI Musical Data Interchange has a transfer rate of 300 times that of MIDI SDS, it can also distribute stereo or multi-channel sample fields also can process files that are more than two megawords in length transmitting the associated information [such as pitch values, sample number range etc.] as well as sound patch and device specific set-up parameters – all of which cannot be achieved via the use if MIDI SDS. Thus, some samplers offer SCSI connectivity because of the inherently fast rate of data transfer associated with the medium as well as other aforementioned technological advantages. [1]
07 - What is 'tracking'?
Tracking is
08 - Why might an LFO be used with a sample?
An LFO – Low Frequency Oscillator can be used with a sample to modify the electrically generated characteristics of the waveform. The effect of a LFO on a sample is that it alters the pitch as well as timbre of the sample.
09 - What filters are commonly offered with contemporary samplers?
Filters that are commonly offered with contemporary samplers are as follows are High Pass Filters, Low Pass Filters, Band Pass / Peak Filters and Band Stop / notch filters.
10 - How do 'soft samplers' such as Gigasampler store their samples?
Soft samplers such as Gigasampler store their samples in the computer memory, as they are software-based samplers.
11 - Why are Zip Drives used with some hardware samplers?
Zip drives are used along with some hardware samplers as they are a source of additional memory which can be used for storage of clips, and can free up space on the computer’s memory thus allowing for faster processing speeds.
12 - How can a sampler be used to add a 'vinyl effect' to a song?
To achieve a vinyl effect via the use of recorded samples which highlight the crackling and familiar sonic variants associated with vinyl records. These samples can then be zoned along with other samples thus on playback the vinyl effect will be achieved.
13 - What benefits do samplers with multiple physical outputs have?
The benefits of a sampler with multiple physical outputs are that the samples can be routed to effects devices as well as a console for processing.
14 - What are the benefits of working with mono samples over stereo samples?
The benefits of working with Mono samples as opposed to stereo samples are that you get the envelope characteristics and the tonal quality of the sample but utilising less memory, also, a stereo effect can always be attained from mono samples after the fact via the use of effects devices.
15 - What MIDI control messages can a typical sampler read?
MIDI control messages that can be read by a typical sampler are Velocity, Note On, Note Off, Program Change and Bank Select
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using a sampler?
An instrument with a long sustain can be created from one with a short sustain by looping the sustain along zones of the sampler until the adequate sustain parameter is achieved.
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
Aslide from an MIDI lead, other connections that are or could be made from a hardware connector are SCSI, MLan, Fire Wire, USB.
18 - How does a hardware sampler ensure that there is no latency?
There is no latency associated with a hardware sampler as the samples are stored in RAM [random Access Memory] and sometimes the cache section of the memory which has a faster access time than normal RAM.
19 - How can sample looping be used to save storage space?
Through sample looping, a finite memory space in RAM – Random Access Memory is sustained for a long period of time as well as disk-based memory. Thus space is saved and can be allocated for other processes. [1]
20 - What are the main requirements of a glitch free loop?
The main requirements for a glitch free loop – one that transcends seamlessly, not containing clipping, popping or ticking are firstly the waveform shape and amplitude at the beginning of the loop should be identical to that at the end of the loop i.e. the wave crossover points should be identical, secondly the loop itself must not consist of any unwanted frequencies and events that will negatively impact the process; namely the loop itself must be glitch free, finally the loop chosen must be relevant to be looped in the first place, it should be a segment that does not change with respect to amplitude and composition in the song for a period of time. [1]
21 - Why are closed and open hi-hats often sent to the same mute group?
Closed and open hi-hats are often sent to the same mute group because
22 - On hardware samplers, how much sampletime would you typically get out of 64MB storage?
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
To achieve a chorus effect using a sampler that does not have an effects section, I would most likely use the splitting or mapping technique. I will then identify from the original mix, the parameters of my loop. Then I would begin on the task of assigning zones, for each zone I will identify the notes or possibly octaves that I would want in my choir mix as well as velocity layers will be set for the more intense parts. The result played back simultaneously, would be multiple loops playing at different intensities and frequencies attaining a choir effect.
24 - How might you soften the start of a drum sample (single hit)?
Most Likely, I would soften the start of a drum sample [single hit] by adjusting the envelope of the waveform at the initial attack, I would not shorten the attack as to preserve the characteristics of the sound - I would likely prefer to assign a volume envelope to the sample and modify the volume level of the initial attack building back up the level with a rapid curve so that the rest of the Phase of the envelope can attain its general characteristics.
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a sample?
The phase/s of an envelope that I would most likely place a loop would be determined by the rate of decay from the initial attack to the final release as well as I would be guided by the characteristics of the song itself –tempo, patterns. For example for a Trombone, which has a long sustain and release I would place the loop in the latter phase release phase, for a Snare Drum, I would most likely place the loop in the latter sustain section as the release is rapid, and for a Cymbal Crash I would most likely place the loop in the release phase as the sustain is prolonged and the release is gradual. Thus loop placement is subjective but it should be adhered that the crossover points are identical to allow for smooth transition – no matter what phase of an envelope is chosen. [1]
Reference
[1] modern recording techniques, DM Huber, R Runstein |
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Thu Apr 14, 2005 3:13 am |
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chemira
Joined: 03 Jan 2005
Posts: 50
Location: Nova Scotia Canada Eh! |
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Week 6 Music Technology
01- What are the logistical disadvantages of multisampling?
Multisampling has a main disadvantage in the size of the files that need to be stored for each instrument. The end result is a more realistic sounding sample but at a cost of increased storage space. [1]
02- What is the importance of 'zero crossing' with sampled material?
The importance of setting a samples start and end point at a zero crossing is to ensure that as the sample is triggered there will not be any detectable click or pops. [2]
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
Problems that may occur while sampling from vinyl are that the pitch and tempo may be inaccurate on the original recording and may need correction or converted. Even if the RPM of the album/record is precisely 33 1/3 the original recording may have been off pitch or off tempo. [3]
04 - What are the benefits of multisampling?
Multi sampling will be a more accurate representation of how the instrument sounds in more varying degrees regarding attack, technique used, range and environment. A violin bowed or plucked, single string or double will impart different overtones and realism. Room sounds and distant microphones on drums can impart more realism on the close miced samples. [3]
05 - What are the advantages of USB connectivity for a sampler?
Large sample libraries can be stored transferred and triggered from a USB external drive or storage medium. Several drives can also be connected extending the size of the sampled library. Fast transfer rates can be exchanges to and from external drives and several samplers can be connected and driven by one sampler. USB can transfer audio files along with midi messages which can make it very flexible for all audio sampling tasks.
06 - Why do some samplers offer SCSI connectivity?
Some samplers offer SCSI connections to easily facilitate connection of External SCSI Drives Hard drives or optical drives allowing fast transfer of large sample libraries. Choices can also be made regarding format and type of drives software used or editing parameters. Cross file format sharing and conversion or editing can be done on separate computers as long as they have SCSI interface capabilities. [4]
07 - What is 'tracking'?
Still looking!!
08 - Why might an LFO be used with a sample?
A LFO can be used to create vibrato or slight variations on the sample to create more realism.
09 - What filters are commonly offered with contemporary samplers?
High Pass, Low pass Notch filter and peak filters are commonly offered on contemporary samplers. [5]
10 - How do 'soft samplers' such as Giga sampler store their samples?
Giga Sampler stores the files in the .GIG format on a hard drive and streams them directly from the hard drive. [5]
11 - Why are Zip Drives used with some hardware samplers?
Zip drives are used to upload sound libraries into the Sampler. Zip Disks are small and were used with a large number of host hardware making library exchanges easier. Although there was promise with the Zip drive the reliability could be low regarding compatibility. [6]
12 - How can a sampler be used to add a 'vinyl effect' to a song?
Several Samplers employ effects called “Vinyl Sim” or Vinyl plug ins that super impose the crackle and hiss that real vinyl will exhibit.
13 - What benefits do samplers with multiple physical outputs have?
A Sampler that has multiple outputs can allow more creative transformations of the sounds outside of the sampler. Dynamic, EQ or special effects can impart unique signature onto the sounds that were standard samples.
14 - What are the benefits of working with mono samples over stereo samples?
A mono sample will take up half of the space that a stereo sample would take up. This also holds true for the amount of RAM that is required to store the sample before it will be played.
15 - What MIDI control messages can a typical sampler read?
A Sampler can read On, Off, Volume, Expression, Sustain or Hold Pitch and bend MIDI messages. [7]
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using a sampler?
The middle portion of the sample can be looped after the attack cues and before the decay. This requires a sample from the instrument data that has zero crossings at the onset and end of the loop that is to be repeated.
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
A hardware sampler may have a host of input and out put connections in either digital or analog formats. The Sampler may have Firewire IEEE1394, USB, SPDIF, AES/EBU, SCSCI for digital formats or Stereo IN out or multi channel outputs.
18 - How does a hardware sampler ensure that there is no latency?
Hardware samplers store the Samples in Ram which had an unperceivable amount of delay.
19 - How can sample looping be used to save storage space?
Sample looping can save space by only storing the segments of a sample that are unique to the sound. By only storing what is required the file size will be smaller.
20 - What are the main requirements of a glitch free loop?
Glitch free loops need to have Zero crossing start and end points and they must be of similar phase and amplitude so the transition points have no pops fades or surges.
21 - Why are closed and open hi-hats often sent to the same mute group?
When one sound is playing the other should not be playing. The closed hihats would mute the open hats and the open hats should not be playing while the closed are playing.
22 - On hardware samplers, how much sample time would you typically get out of 64MB storage?
Quote “The bit-rate of uncompressed audio can be calculated by multiplying the sampling rate by the resolution (8-bit, 16-bit, etc.) and the number of channels. For example, CD Audio (or a WAV file extracted from a CD) has a sampling rate of 44,100 times per second, a resolution of 16 bits and two channels. The bit-rate would be approximately 1.4 million bits per second (1,411 kbps).” Unquote. This will render approximately 5MB per minute giving 64MB 12.8 minutes of audio storage. [8]
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
By utilizing two sends, one with a LFO acting on a VCO to raise and lower the pitch and the other straight through un affected. By recombining the two signals their relative difference would simulate a Chorus pitch shifting effect.
24 - How might you soften the start of a drum sample (single hit)?
By slowing down the attack envelope the drum hits attach will be reduced thereby softening the sample.
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a sample?
The sample would be heard in the sustain of the envelope. The attack would fade it in the delay would create the fade in ramp the sustain is the unaffected sample and the release is the fade out volume.
[1] http://www.homeplace.org.uk/Music%20Tech%20GlossaryL-Q.htm
[2] http://www.chellman.org/audio/zero_crossing.html
[3] http://www.tweakheadz.com/Sampling_Tips.html
[4] http://www.soundonsound.com/sos/oct99/articles/samplers.htm
[5] http://www.soundonsound.com/sos/dec98/articles/gigasample.143.htm
[6] http://www.soundonsound.com/sos/jan98/articles/emuesi.htm
[7] http://www.multitrackstudio.com/sampler.php
[8] http://www.teamcombooks.com/mp3handbook/11.htm
Still looking for tracking |
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Sat Apr 16, 2005 8:38 pm |
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thx1138
Joined: 07 Jan 2005
Posts: 21
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01- What are the logistical disadvantages of multi-sampling?
A disadvantage of multi-sampling is the amount of space needed to store the samples. A lot of good quality samples will take up a lot of memory.
02- What is the importance of 'zero crossing' with sampled material?
When looping a sample, zero crossing ensures that there are no clicks or pops at the start and end points of a loop. Basically the start and end points should be at exactly the same level (preferably zero).
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
The speed of the turntable may not be entirely constant, which will cause alterations in the pitch and tempo of a sample taken from vinyl.
04 - What are the benefits of multi-sampling?
A sampled note generally only sounds natural for a couple of semitones either side of its original pitch. Multi-sampling is where samples are taken from a range of notes or keygroups to ensure samples sound realistic over several octaves.
05 - What are the advantages of USB connectivity for a sampler?
The advantages of a sampler that has USB connectivity is that the samples contained on it can be downloaded to a computer freeing up more sample memory on the sampler itself.
06 - Why do some samplers offer SCSI connectivity?
A sampler may have SCSI connectivity so that storage devices such as hard drives and CD ROM drives may be attached to store banks of samples.
07 - What is 'tracking'?
Tracking is when filters are used for more realistic sounding samples when playing a note at a higher pitch and frequency. The higher the note the higher the cut off filter will be.
08 - Why might an LFO be used with a sample?
LFO might be used on a sample for the same reasons it would be used on a synthesiser, to modulate the sample in some way.
09 - What filters are commonly offered with contemporary samplers?
On a contemporary sampler the filters that are commonly offered are: Low pass, Hi pass and Band pass filters.
10 - How do 'soft samplers' such as Gigasampler store their samples?
A soft sampler such as giga sampler stores its samples on the hard disk of the computer, usually in .wav or .aiff formats.
11 - Why are Zip Drives used with some hardware samplers?
Zip drives are often used with some hardware samplers as they are a good, easily portable storage medium with a suitable amount of space on them.
12 - How can a sampler be used to add a 'vinyl effect' to a song?
A sampler could be used to add a vinyl effect to a song by taking a sample of the slight crackling sound of vinyl turning and looping it in the background of a song.
13 - What benefits do samplers with multiple physical outputs have?
Multiple outputs would allow for the samples to be sent to individual tracks on a mixer and various effects could be attached to the various outputs.
14 - What are the benefits of working with mono samples over stereo samples?
The advantages of using mono samples over stereo is the space required to store the samples. Mono samples are a lot smaller than stereo samples and therefore require less storage space and processing power.
15 - What MIDI control messages can a typical sampler read?
A typical sampler can read these kinds of midi signals:
Bank select, note on, note off, program change and velocity.
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using a sampler?
An instrument with a long sustain can be created from am instrument with a short sustain by either having its sustain section 'stretched' or by using a looped sample of the sustain section that continues for the desired sustain time.
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
Aside from a midi lead, other connectors you would expect to find on a hardware sampler would be:
Audio line in and out(s), USB and SCSI connectors and a headphones socket and possibly digital in/out connectors.
18 - How does a hardware sampler ensure that there is no latency?
A hardware sampler ensures there is no latency by having all its samples loaded into its RAM.
19 - How can sample looping be used to save storage space?
Sample looping saves storage space as even though the sample is played multiple times, only one sample is required instead of having the same sample loaded many times.
20 - What are the main requirements of a glitch free loop?
The main requirements of a glitch free loop are the start and end points using zero crossing, or at least being at the same level to ensure there are no unwanted clicks and pops. Also the sample would need to be at an appropriate volume to unsure no clipping.
21 - Why are closed and open hi-hats often sent to the same mute group?
Open and closed hi hats are often sent to the same mute group for realism. An open hi hat sound stops once the hi hat is closed as this happens on a real drum kit, they cant sound at the same time.
22 - On hardware samplers, how much sampletime would you typically get out of 64MB storage?
On a hardware sampler the amount of sample time available with 64MB of storage can be worked out like this:
Sample rate (wavelength) x Sample size (bits) x Channels = bits per second
For maximum storage lets assume the sample are all in mono:
44100 x 16 = 705600 bits per second
divided by 8 to convert to bytes per second = 88200 bytes per second
divided by 1024 to determine kilobytes per second = 86.1 KB s-1
multiply be 60 for KB per minute then divide by 1024 to give megabytes per minute = 5.05 MB per minute.
64 / 5.05 = 12.67 minutes of sample time for 64 MB storage space.
Divided by 2 gives the sample time if all the samples are stereo = 6.33 minutes of storage space.
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
You could double up the sample and modulate the pitch of one of them through an LFO whilst slightly offsetting the two samples to create a slight delay of 20-50 milliseconds.
24 - How might you soften the start of a drum sample (single hit)?
The start of a single hit drum sound can be softened by setting its attack time to a slightly longer value.
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a sample?
The phase of the envelope that I might place a loop in a sample would be the sustain phase of the sample though this would depend on the nature of the sound that had been sampled.
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AcousticalWeaponsDivision/Alex |
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Sun Apr 17, 2005 11:29 am |
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hoaxwagon
Joined: 28 Feb 2005
Posts: 27
Location: Boulder Creek, CA USA |
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MT wk 6 Q&A
01- What are the logistical disadvantages of multisampling?
Multisampling is time consuming and uses a lot of memory.
02- What is the importance of 'zero crossing' with sampled material?
When a sample is created it is important for it to begin and end with a zero crossing to eliminate any
potential for glitches in the sound.
03 - What problems may there be with sampled material from vinyl in terms of pitch/tempo?
04 - What are the benefits of multisampling?
The benifits of multisampling are increased pitch accuracy and a more accurate representation of the
original instrument.
05 - What are the advantages of USB connectivity for a sampler?
USB allows the transfer of data at speeds 50% faster than most parallel connections. No memory
addresses or ID numbers and USB cables are inexpensive and easily obtainable. USB "plug and play"
feature allows users to simply plug in a device and the "hot pluggable" feature lets users switch USB
devices without re-booting.
06 - Why do some samplers offer SCSI connectivity?
So they can be connected to and communicate with a computer. To allow for the transfer of samples
over SMDI, a protocol that uses the SCSI connection.
07 - What is 'tracking'?
Filter tracking is when the keyboard is set up so that the low pass filter responds differently for different
keys or dynamics. Pitch tracking makes it possible for all notes to be voiced although the sample could
just consist of middle C.
08 - Why might an LFO be used with a sample?
LFO can be routed to an assortment of destinations including filter frequency, filter resonance, drive,
pitch, pan and amplitude.
09 - What filters are commonly offered with contemporary samplers?
Anti- aliasing filters , one before the ADC and one after the DCA, and low pass filters are common.
10 - How do 'soft samplers' such as Gigasampler store their samples?
On a hard drive
11 - Why are Zip Drives used with some hardware samplers?
It is an economical way of storing samples. The samplers may not have alot of RAM or drive space.
12 - How can a sampler be used to add a 'vinyl effect' to a song?
The erode function of a software edidor named Squash it can add low frequency hum, like a dodgy pre
amp, and crackle to give the illusion of a sample from vinyl.
13 - What benefits do samplers with multiple physical outputs have?
This will allow you to precisely balance and eq the sound at a mixing board.
14 - What are the benefits of working with mono samples over stereo samples?
Mono sample take up less space in storage and are easier to loop and/or crossfade than stereo
samples.
15 - What MIDI control messages can a typical sampler read?
Bank select, patch select, progragm change, MIDI system and MIDI channel messages.
16 - How can an instrument with a long sustain be created from an instrument with a short sustain using
a sampler?
The sample can be stretched. In squash it this function is called squash/stretch.
In the Sustain part of the ADRR envelope is the part of the sound that can be looped so it sounds for
longer
17 - Aside from a MIDI lead, what other connections are (or can be) made from a hardware sampler?
Balanced analog inputs and outputs, SCSI, USB, digital in and output
18 - How does a hardware sampler ensure that there is no latency?
By using a feature called keep on disk, the samples required don’t have to be loaded into RAM first.
19 - How can sample looping be used to save storage space?
By storing a small portion of the sound
and looping as needed takes up less space.
20 - What are the main requirements of a glitch free loop?
zero crossing, optimum loop length and crossfade. A compressed sample in some cases helps.
21 - Why are closed and open hi-hats often sent to the same mute group?
So that the closed hat can mute the open hat and vise versa. This is possible when in the same mute
group.
22 - On hardware samplers, how much sampletime would you typically get out of 64MB storage?
6 minutes stereo 44.1 khz and double that for mono.
23 - How might you achieve a chorus effect using a sampler that does not have an effects section?
Send MIDI control messages to an effects processor set for chorusing.
24 - How might you soften the start of a drum sample (single hit)?
Shaving a little bit off the attack of an ADSR envelope should give the effect of a softer transiant.
25 - In which phase(s) of the envelope (attack/decay/sustain/release) might you place the loop in a
sample?
The sustain phase of the sound is the place to loop. |
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Mon Apr 18, 2005 12:17 am |
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