EP0961981A4

EP0961981A4 - Portable digital recording device

Info

Publication number: EP0961981A4
Application number: EP98965427A
Authority: EP
Inventors: Peter Kessler
Original assignee: KESSLER INTERACTIVE DIGITAL DESIGNS Inc; KESSLER INTERACTIVE DIGITAL DE
Current assignee: KESSLER INTERACTIVE DIGITAL DESIGNS Inc; KESSLER INTERACTIVE DIGITAL DE
Priority date: 1997-12-23
Filing date: 1998-12-22
Publication date: 2002-11-20
Also published as: EP0961981A1; AU2089599A; WO1999032991A1

Abstract

A system for recording and mixing sound that can concurrently process a plurality of audio input files. The device is based upon a Cyrix class CPU microprocessor mounted on a motherboard with at least about 32 MB of RAM. Two or more logical data reservoirs, each having a storage capacity of at least about 450 MB, are connected to the microprocessor by a conventional system bus. The system is configured so that none of the data files, i.e., the MIDI and the *.WAV files, are stored on the first data reservoir, and that all of the MIDI and *.WAV files, but no other files, are stored on the second data reservoir. Conventional sound and video hardware is also connected to the system via a conventional bus as is a conventional mastering unit. The recording device requires a software operating system effective to support the processing of the audio data files and a conventional audio processing software capable of utilizing both MIDI and *.WAV files (or the equivalent of these files) configured to have a DMA value of at least about 25,000.

Description

PORTABLE DIGITAL RECORDING DEVICE

BACKGROUND OF THE INVENTION The present invention relates to a device and method for recording and mixing sound and particularly relates to a mobile system for making an audio master recording.

DESCRIPTION OF RELATED ART

There are two types of audio data that can be processed on a personal computer ("PC"). The first type of audio data is Musical Instrument Digital Interface ("MIDI") data and the second type is digital audio. MIDI is a means by which computers and electronic musical instruments can communicate. Some MIDI data encodes specific aspects of a musical performances notes; how loud; the type of sound (trumpet, dram, flute) playing the notes, etc.; while other MIDI data is more general in nature. Together, MIDI messages represent an entire language of musical actions, and can convey all the details of a complete symphony or a simple hymn. When MIDI data reach their destination, for example a synthesizer, the synthesizer operating system interprets the MIDI data as a series of instructions that usually result in the production of a sound. This sound must be amplified, so the synthesizer will typically be connected to an amplifier or mixer.

MIDI technology has developed substantially in recent years and, as a result, most conventional PCs can process a plurality of MIDI channels. Thus, it is not unusual for a PC to be able to substantially concurrently process 16 MIDI channels, each of which may constitute a plurality of tracks. However, it must be born in mind that MIDI is only applicable to MIDI instruments

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SUBSTΓΠΠΈ SHEET (RULE 26) which is a small fraction of the world of recorded music.

Digital audio, on the other hand, is a numeric representation of sound. Digital audio is sound stored as numbers and it is much more complex to process on a PC than MIDI data. A PC digital audio data file is typically characterized as a *.WAV file. Despite the many advances, heretofore, PC based systems have been limited to the concurrent processing of less than about 17 tracks (or *. WAV files), and usually fewer than about 10 tracks.

The ability to process audio data on a PC requires audio processing software. While there are several venders on the market, Cakewalk Pro Audio appears to be the standard PC audio processing software. The manufacturer of Cakewalk Pro Audio asserts that this software can handle as many simultaneous audio events as the hardware allows. However, a relatively slow computer or hard drive, may have trouble concurrently playing back more than 6 or so digital audio events. Lowering the polyphony setting may ease the burden on the computer and hard drive. Each unit of polyphony consumes 64KB of memory at 44. 1 kHz or 22KB at 11kHz.

Without sufficient memory, an audio processing software program may steal voices, much like a polyphonic MIDI synthesizer.

High quality digital audio also consumes large amounts of hard disk space. For example, it is estimated that each minute of digital audio, per track, requires the following amount of hard disk space:

In other words, 1 minute of 16 track digital audio requires 80 MB of storage capacity for recording. However, some audio processing software, such as Calkwalk Pro Audio, can, upon processing, store the audio data more efficiently than this theoretical requirement.

Moreover, while, the number of tracks conventional audio processing software such as Cakewalk Pro Audio can process is theoretically unlimited, each system imposes practical limitations. For example, the PC's CPU speed, and the hard drive's seek time and transfer rate and the sample rate used to record or import audio files combine to limit the number of tracks of digital audio that can be processed substantially concurrently.

The audio sampling and recording is done at a set rate which determines the highest frequency that can be rendered. Mathematically, the highest frequency that can be rendered is F(s)/2 where F(s) is the sampling frequency. However, as 24 kHz is beyond than the upper threshold of human hearing, the sampling rates greater than about 48 kHz do not improve the quality of the recorded sound.

When audio is digitized, the data is sampled and quantized. Quantization is done at a given resolution, the sample depth (bits per sample). This depth determines the dynamic range (i.e., range of loudness-to-softness) that can be rendered. Since each bit of resolution effectively doubles this range, 8-bit audio gives 48dB of dynamic range (ie, 6dB/bit times 8 bits), while 16- bit audio gives 96dB of dynamic range. High end conventional audio processing software such as Cakewalk Pro Audio support 16-bit audio (2 bytes per sample) and sampling rates of 11 kHz, 22kHz and 44kHz (CD quality) .

To calculate the theoretical maximum amount of tracks a computer can process, multiply the sampling rate, the bits per sample, and the number of channels, to arrive at an audio data rate. For example, the per-channel data rates for 11, 22 and 44 kHz sampling rates using 16-bit audio are: 11 kHz = 11025 samples/sec * 2 bytes/sample = 22050 bytes/sec

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SUBSTΓΓUTE SHEET (RULE 26) 22 kHz = 22050 samples/sec * 2 bytes/sample = 44100 bytes/sec 44 kHz = 44100 samples/sec * 2 bytes/sample = 88200 bytes/sec

Thus, playing 8 channels (tracks) of 44 kHz audio requires a sustained data rate of 88200*8 - 705,600 bytes/sec.

If the system cannot move the data at the appropriate rate, the audio won't play smoothly. Thus, the system's data transfer rate limits the maximum number of tracks that can be processed by a system.

The system's data transfer rate can be found by conventional utilities such as Norton SYSINFO. For example, if the digital audio is stored on a hard disk and that hard disk has a transfer rate of 1.4MB/sec and the audio processing is set at 44 kHz at 2 bytes per sample, them the system is limited to:

(1.4MB/sec)/(88200 bytes/sec/track) = 16 channels (tracks). Thus, even a Cray supercomputer whose hard disk has a transfer rate of 1.4 MB/sec cannot process more than 16 channels (tracks).

Moreover, playing back digital audio is more complex than simply copying the data from the hard disk to the sound hardware/digital audio interface. Assume 20% of the CPU's resources are dedicated to mixing audio, a generous estimate, on a 33mhz 486, 20% equals about 6M CPU cycles per second. Assume further that it takes minimum about 16 cycles to mix a single sample of digital audio (another generous estimate), mixing a full second of audio at 44kHz requires:

16*44100 = 705K cycles per channel. Dividing the number of cycles per second by the number of cycles required per channel per second yields the maximum number of channels the system could process. Here: (6M cycles/sec) / (705K les/channel) = 8.5 channels Therefore, even assuming that 20 percent of the CPU is devoted to processing the

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SUBSTΓΓUTE SHEET (RULE 26) audio data, the maximum number of channels a 486 33 MHz system can process is 8.

It has also been noted that when processing 16 or more tracks of digital audio at 44J kHz, the sound frequently begins to wobble, drift, and stutter the system frequently locks up or seizes. These problems are believed to be related to problems in the data transfer rate and in over-running the CPU and the RAM memory.

Heretofore, another common problem has been how to create the CDR master. Oft time, to create a CDR master, the digital wave audio files are transferred between several media, for instance dat or other multi-track tape systems.

OBJECTS

It is an object of the present invention to provide a PC type system that can concurrently process more than about 16 tracks of digital audio.

SUMMARY OF THE INVENTION

The present invention provides a system for recording and mixing sound. The device of the present invention currently process a plurality of audio input files. The device of the present invention is based upon a CPU that performs floating point operations in a manner akin to that of the AMD and Cyrix "Pentium" class microprocessors (such microprocessors are, believed to be 64-bit enhanced x87 -compatible with at least about 64 Kbit onboard cache and at least about 6 execution pipelines ), and unlike Intel Pentium and Pentium pro microprocessors. The microprocessor is mounted on a motherboard that has a cache of that least about 256K. Also functionally connected to the microprocessor is at least about 32 MB of RAM.

Two or more data reservoirs are connected to the microprocessor by a conventional system bus. The data reservoirs have a storage capacity of at least about 450 MB but typically

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SUBSTΓΓUTE SHEET (RULE 26) less than about one GB. The system is configured so that none of the data files, i.e., the MIDI and the *.WAV files, are stored on the first data reservoir, and that all of the MIDI and *.WAV files, but no other files, are stored on the second data reservoir. It is further preferred that the files on the system of the present invention are the ceratin software including the software used to read and write to the several devices used in the device of the present invention, the audio data processing software, and the MIDI and the *.WAV files.

Conventional sound and video hardware is also connected to the system via a conventional bus.

The recording device of the present invention additionally has a mastering unit. Typically, the mastering unit is a drive capable of recording on to a high quality audio recording media such as CD ROM, DVD mini-disk or DAT.

The recording device of the present invention requires a software operating system effective to support the processing of the audio data files. Typically, the software operating system is a Windows type operating system. Additionally, the recording system of the present invention utilizes a conventional audio processing software capable of utilizing both MIDI and *.WAV files (or the equivalent of these files). The ideal processing software is configured to have a DMA value of that least about 25,000.

In a preferred embodiment of the present invention intergrated audio mixing system is assembled in a small, i.e., less than 1700 cubic inches, volume.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a front view of an embodiment of the device according to the present invention; Fig. 2 is a schematic illustration of a motherboard that is useful in the device of the

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SUBSTΓΓUTE SHEET (RULE 26) present invention;

Fig. 3 is a broken out schematic illustration of a device of the present invention;

Fig. 4 is a top view of the embodiment of the device shown in Fig. 1 in the closed position; Fig. 5 is a side view of the embodiment of the device shown in FigJ in the open position;

Fig. 6 is a see through side view of the embodiment of the device shown in Fig. 1 in the closed position;

Fig. 7 is a see through top view of the embodiment of the device shown in Fig. 1 taken below the top of the device; and

Fig. 8 is a rear view of the embodiment of the device shown in Fig. 1 in the closed position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The recording system of the present invention processes both MIDI and digital audio files such as *.WAV files. Typically, the recording system of the present invention can substantially concurrently process a plurality of MIDI and *.WAV files. For example, a typical embodiment of the present invention can substantially concurrently process 16 *.WAV files, and a preferred embodiment of the present invention and can substantially concurrently process 24 *.WAV files. A further preferred embodiment of the present invention can substantially concurrently process at least about 32 *.WAV files.

The device of the present invention is based upon a CPU that performs floating point operations in a manner akin to that of the AMD and Cyrix "Pentium" class microprocessors, but unlike Intel Pentium .and Pentium pro microprocessors. For example, the AMD K5 and K6

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SUBSTΓΓUTE SHEET (RULE 26) microprocessors as well as the Cyrix P120+, P150+, P166+, P200+ and P233+ microprocessors are each suitable for use in the present invention (hereinafter a "Cyrix class CPU"). It is further preferred that a pair of matched microprocessors are employed in the device of the present invention. In a preferred embodiment of the present invention, there is an air flow channel that traverses the CPU. For instance, an intake fan may be mounted on the front of the device of the present invention and an output fan may be mounted on the rear of the device so that air flows continuously from the front, over the CPU, and out the rear of the device.

The microprocessor is mounted on a conventional motherboard that has a cache of that least about 256K, and preferredly the motherboard has a cache of that least about 512K, and more preferredly the motherboard has a cache of that least about 1 MB. A preferred motherboard for use in the present invention is the Tyan Tomcat 3 motherboard model 1563D. It is also desired that the motherboard contain the Intel HX or TX chipset or another socket 7 chipset such as the Intel HX 430 chipset. Moreover, it is preferred that the chipset is not a VX FX or LX chipset.

It is believed that it is necessary to have at least about 32 MB of RAM installed to be able to substantially concurrently process about 16 *.WAV files (or any other digital audio file), and it is believed that it is necessary that at least about 40 MB of RAM are installed to substantially concurrently process about 24 *.WAV files. To substantially concurrently process 32, or more, digital audio files it is believed that the system must have at least about 48 MB of RAM installed. In this regard, a system according to the present invention having 48 MB of RAM has been able to mix 70 digital audio files to obtain a 2 track stereo *.WAV file.

Two or more data reservoirs are connected to the microprocessor by a conventional system bus. Typically, the data reservoirs employed in the present invention are hard disks. The data reservoirs have a storage capacity of at least about 450 MB, but typically less than about

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SUBSTΓΓUTE SHEET (RULE 26) one GB. The system is configured so that none of the data files, i.e., the MIDI and the *.WAV files, are stored on the first data reservoir, and all of the MIDI and *.WAV files, but no other files, are stored on the second data reservoir. More than one data reservoir can exist on a single physical drive in the form of partitioned logical drives, and it is preferred that at least two of the data reservoirs employed in the present invention are logical drives located on the same physical, drive. In a particular preferred embodiment of the present invention, the data reservoir is a single physical drive having three partitions, or logical drives. Preferredly, each of the logical drives has a data storage capacity of between about 450 and 800 MB.

If the data reservoir is a hard drive, the hard drive head desirably rotates at least about 3000 φm, preferably at least about 4000 φm, and most preferably at least about 5,000 φm. Additionally, it is preferred that the hard drive is rated "AV" (i.e., "audio visual") capable. It is also desired that the hard drive has a seek time of about 16 msec, or less, and it is preferred that the hard drive has a seek time of about 10.5 msec, or less. A data transfer rate of 16 MB/sec is a useful data transfer rate for a hard drive employed in the device of the present invention. Example of useful hard drives include SCSI and fast ATA-2 EIDE hard drives.

Also connected to the conventional system bus is conventional video hardware to read, transcribe and power the video display. The video hardware should be able to support a display of least about 640x480 lines with 256 colors. In a preferred embodiment of the present invention, the video controller hardware is surface mounted on the motherboard. It is further preferred that the video hardware is able to support 24 bit true color (i.e., 16 million colors). A useful video card for the practice of the present invention is the Avid ROM 12S31 video card wherein the video card ROM chip is matched to the video display unit. However, as the standard video cable is too bulky, it is preferred that a 50 pin ribbon cable is used to connect LCD to the video hardware and as a result, the video cable connection superficially resembles a SCSI connection.

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SUBSTΓΓUTE SHEET (RULE 26) Consistently, a conventional display unit capable of the display of 640x480 lines with at least about 256 colors should be connected to the conventional video hardware. In a mobile embodiment of the present invention, it is preferred that the conventional display unit is an LCD and it is further preferred that the LCD display unit has a viewing resolution of the least about 200 nits. It is still further preferred that LCD has viewing resolution of at least about 240 nits and it is most preferred that LCD display has a viewing resolution of at least about 270 nits. A particularly useful LCD is manufactured by the Shaφ company under the TFT LCD LQ 12S31 trade name.

Additionally, the device of the present invention has conventional sound hardware. The sound hardware should be at least an 8 bit sound hardware, but it is preferred that the sound hardware is a 16-bit sound hardware. It is still further preferred that the sound hardware is least a 20 bit sound hardware. Additionally, it is also preferred that the sound hardware supports full duplex (i.e., the hardware preferredly is able to simultaneously play back one track while recording another track). A particular useful sound hardware is the Audiotrix 3 DXG sound card sold b Mediatrix.

It is also desired that the sound hardware supports at least about 8 note polyphony, preferably at least about 24 note polyphony, and more preferably, the sound hardware supports at least about 32 note polyphony.

The sound hardware desirably also supports multi-timberality. Sound hardware useful in the present in the practice of the present invention can support 2,4,8,12,16 or higher multi - timberality. However, it is preferred that the sound hardware employed in the practice of the present invention support the least about 8, preferably at least about 12, and most preferably, at least about 16, multi-timberality.

It is also desired that the sound hardware supports adjustments for bass, treble, 3-D control, and provides conventional "on-board instruments", "drum kits" and "on-board stereo effects" (such as is reverb). It is also preferred that the signal to noise ratio of the system of the present invention is less than about 87 dB.

Typically, the sound hardware will have a line input (such as a stereo line input), a MIDI input and a MIDI output. The sound hardware may also have a MIDI thru. In most instances, the line input is from either a microphone or a tape. Additionally, it is desired that the line input is sampled at a rate of least about 11 Hz, it is more preferable that the input is sampled at a rate of at least about 22 Hz, and it is further preferred that the input is sampled at a rate of at least about 44J kHz (i.e., CD quality), and it is most preferred that the input is sampled at a rate of at least about 48 kHz. In an alternative embodiment of the present invention, the sound hardware has 2 or more digital audio inputs. For instance, the sound hardware of the device of the present invention could have between 3 and 48 digital audio inputs. The device of the present invention having between 3 .and 48 digital audio inputs could be utilized to record live music as raw data. Currently, despite using a plurality of audio inputs, live music is recorded as a combined mixed audio data file, typically 2 stereo tracks, so that the sound engineer cannot remix the audio data once it is recorded. However, by using the system of the present invention to record the live music as raw data, the sound engineer can, after the recording is completed, mix and remix the audio data until the desired sound is obtained.

In another alternative embodiment of the present invention, the digital audio data files are recorded on a large data reservoir, for instance a 9 GB hard drive with a fast access time. In this manner, 60 plus minutes of 24 tracks of digital audio input sampled at 44J Hz unmixed live music could be concurrently recorded. At a latter date, a sound engineer can then mix these digital audio files to obtain the optimum sound for recording onto the master disk.

In yet another embodiment of the present invention, unmixed digital audio data may be stored on a removable data reservoir, such as a 2GB JAZ (by Iomega) Disk.

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SUBSTΓΓUTE SHEET (RULE 26) While it is desired that the recording device of the present invention has pair of speakers, substantially any conventional speakers that can be driven by the devices output may be use, particularly useful speakers are the Fiber Acoustics model MMS-1 speakers.

The recording device of the present invention additionally has at least one mastering unit. Typically, the mastering unit is a drive capable of recording onto a high quality audio recording media such as CD ROM, DVD mini-disk or DAT. A preferred drive capable of recording onto a high quality audio recording media is the Ricoh MediaMaster CD-RW MP6200S dual function rewritable-recordable CD recording drive, which has a data transfer rate of about 5 MB/sec, an about 1 MB buffer and a SCSI 11 interface. In a typical embodiment of the present invention, the creation of the high quality audio recording media master uses Adaptec's Easy CD Pro 95 and Adaptec Direct CD.

The recording device of the present invention requires a software operating system that is effective to support the processing of the audio data files. Typically, the software operating system is either: Windows (3.0 or higher, including Windows 95), NT (3.5 or higher), Unix, or OS/2 (waφ or higher) (collectively, hereinafter, a "Windows operating system"). Preferredly, the software operating system is a Windows 95 (or a more recent version) operating system.

Additionally, the recording system of the present invention utilizes a conventional audio processing software capable of utilizing both MIDI and *.WAV files (or the equivalent of these files). The ideal processing software is configured to have a DMA value of that least about 25,000. A preferred audio processing software is the Cakewalk Pro Audio program. If the

Cakewalk Pro Audio program is used, the program should be at least version 4.0. However, it is also preferred that if the audio processing software is the Cakewalk Pro Audio program that the version is not version 6. Version 5.0 is the more preferred version of the Cakewalk Pro Audio program for use in the device of the present invention. It is also desired that the device of the present invention includes a conventional high

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SUBSTΓΓUTE SHEET (RULE 26) quality audio data reader such as a DVD, a mini-disk or a CD-ROM reader or a DAT player. In an alternative embodiment, the high quality audio data reader is a second drive capable of creating a master.

In addition to the above enumerated components, the device of the present invention also has the appropriate conventional controllers. For example if the data reservoir is an IDE hard drive, the system has an IDE controller hardware. Or, if the mastering unit is a SCSI devise, the system has SCSI controller hardware. Desirably, any such controllers are surface mounted on the motherboard.

It is also preferred that the digital audio data is not compressed by a program such as DoubleSpace and Stacker. However, it is desirable that the digital audio data is compacted. A preferred means of compacting the digital audio data is by deleting the dead space in the *.WAV files. The dead space may be deleted by using the edit feature in an audio processing program such as Calkwalk Pro Audio. In such a process, the *.WAV file is typically split and the split containing the dead space is deleted. After deleting the dead space, the *WAV file may occupy half, or less, of the space on the data reservoir originally occupied by the *.WAV file.

After deleting the dead space, the *WAV files are mixed, i.e., combined, to form a 2 track stereo *.WAV file. As a result of eliminating the dead space and mixing, the 600 MB that are required to store 5 minutes of 24 track digital audio are reduced to about 50 MB of a 2 track stereo *.WAV file. By cutting out the dead space in such a manner, the amount of storage space necessary to store the master files is dramatically reduced. Moreover, after eliminating the dead space, the *.WAV file so prepared is quieter and cleaner than the *.WAV file before this step. Furthermore, by eliminating the dead space, the system's cpu is able to operate on the digital audio and the MIDI files more efficiently. After the dead space has been eliminated from the relevant files, in a preferred

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SUBSTΓΓUTE SHEET (RULE 26) embodiment of the present invention, the dead space eliminated *.WAV files are mixed to produce an appropriately mixed audio data file. In a further preferred embodiment of the present invention, this new mixed digital audio files are stored on a staging area before being written to a high quality digital audio recording media. It is still further preferred that this staging area is not part of either the logical drive containing the application programs or the logical drive containing the *.WAV files.

As shown in Fig. 1, the preferred system of the present invention is substantially mobile. Specifically, it is desired that the system of the present invention has a volume of less than about 1700 cubic inches, it is preferred that the system of the present invention has a volume of less than about 600 cubic inches.

It is also preferred that the system of the present invention has a mass of less than about 30 pounds and it is further preferred that the system of the present invention has a mass of less than about 15 pounds.

Turning now to the drawings, Fig. 1 shows a front view of a device 100 according to the present invention. On the bottom, and on one side, there are mounted on device 100 a plurality of feet 110. On the side without feet 110 is handle 120. Front panel 130 is secured to device 100 by a plurality of hex screws 140. Built into front panel 130 is grating 150 which abuts an unseen 10 intake fan mounted within the device next to grating 150. Also seen in this view is 3.5 inch floppy disk drive 160 and a means of recording onto high quality digital audio recording media 165. Additionally, power switch 170 and reset switch 176 are on the front panel 130 under their corresponding LEDs 172 and 174. Finally, front panel 130 has release button 155 which released an unseen engagement means that keeps pivotable panel 180 in a close position until released.

Pivotable panel 180 holds and protects LCD display panel 190.

Fig. 2 schematically illustrates a motherboard 200 that is useful in the device of the present invention. Functionally connected to motherboard 200 are a mouse connector 210, a

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SUBSTΓΓUTE SHEET (RULE 26) SCSI controller 220, an IDE controller 230, a Cyrix class CPU 240, an Intel HX 430 chipset 250, an on-board cache 260, a sound hardware 270 and a video controller 280.

Fig. 3 presents an exploded view of a device 300 according to the present invention. As assembled, components 320 - 340 reside within case 350 with screen 310 desirable pivotably attached to one edge of case 350. In a preferred embodiment of the device of the present invention, in back of screen 310 is a shell that when screen 310 is pivoted so that it is substantially parallel and im proximity to keyboard 320 the shell on the back of screen 310 acts with case 350 to form a protective casing.

Within case 350 and typically substantially on the bottom of the inside of case 350, is mounted a motherboard 340. Motherboard 340 is mounted in a conventional manner. Above motherboard 340 within case 350 are a variety of conventional components. Fig. 3 illustrates the presence of a mouse connector 331, a MIDI IN/OUT connector 332, a line out 333, a mike in 334, a CD-ROM 335, a hard disk 336 and a mastering drive (e.g., a CD-R drive) 337.

In an alternative embodiment of the present invention, a pointing device is used either to supplement or to replace the keyboard. For instance, a Manta brand pointing device which connects via a serial port may be effectively used in the practice of the present invention.

Fig. 4 shows a top view of device 100 shown in a front view in Fig. 1. In this view, on one side are feet 110 and on the opposite side is handle 120. Also in this view, pivotable panel 180 is in a closed position. Fig. 5 shows a side view of device 100 shown in a front view in Fig. 1. In this view, feet

110 are on the bottom and handle 120 is on the side from which this view is taken.

Fig. 6 is a see through side view of a portable device 100 according to the present invention in the closed position. In this view, on the top and in a closed positing, pivotable panel 180 rests and protects and supports LCD display 190. Below LCD display 190 is an input device 610, such as a keyboard and/or pointing device. Floppy disk drive 160 and a means of

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SUBSTΓΓUTE SHEET (RULE 26) recording onto high quality digital audio recording media 165 as well as handle 120 are each seen in this view. Additionally, functionally attached to motherboard 650 are cpu mountings 640, cards 630 which include the sound and the video hardware as well as the SCSI controller, and power supply 621. Fig. 7 is a see through top view of device 100 taken at about handle 120. Again, floppy disk drive 160 and a means of recording onto high quality digital audio recording media 165 are each seen in this view. Also seen in this view is motherboard 650, cpu mountings 640, cards 630, and power supply 620. Motherboard 650, which is held and positioned by mountings 720, has a plurality of ISA slots 730 and PCI slots 740 as well as memory banks 750. Additionally, data reservoir 760 can be seen in this view.

Fig. 8 is a rear view of device 100. Again, feet 110 are mounted on the bottom and on one side of device 100 and handle 120 is mounted on the other side. The rear panel is also mounted to device 100 by a plurality of hex screws 140. This drawing shows power connection 810 and 815 which provide for male and female connections. Next to power connections 810 and 815 is grating 850 which abuts an unseen output fan mounted within device 100 mounted next to grating 850. Lower and to the right of grating 850 is external input device connector 820 to which an external keyboard or mouse could be connected. Next is external video port 840 and parallel port 860 which are under serial ports 865. SCSI connector ports 870 are next followed by sound card ports 830. In a preferred windows 95 operating system environment, desirably, the system is configured using the Windows 95 Network Setting to alter the stacks and buffers and not to link the system to any other system. This configuration increases and reapportions the RAM utilization in the device.

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SUBSTΓΓUTE SHEET (RULE 26) COMPARATIVE EXAMPLE I

A Compaq Presario model 9546 mini tower personal computer with an Intel 120 MHz cpu was purchased from a retail outlet with a 256 K cache, a 2J GB Quantum Fireball AV hard drive, and an S3 video driver. The sound card that came with the system as purchased was replaced by an Audiotrix Pro sound card sold by Mediatrix and the system memory was increased to 64 MB RAM.

The hard drive was partitioned into 3 logical drives, one (1 GB) containing the system and application files, and two (500 MB each) containing only MIDI and *.WAV files. The operating system, Windows 95 and a copy of Cakewalk Pro version 5.0 was installed on the logical drive containing the system and application files.

Using the wave profiler (the auto-configuration aspect of the Cakewalk program), and recording at a 44J Hz sampling rate, the system became unstable as the third track was added and the system invariably froze during the addition of a fourth track of digital audio.

When the sampling rate was reduced to 22 Hz, more tracks of digital audio could be processed. However, the system became unstable as the tenth track was added and the system invariably froze during the addition of an eleventh or twelfth track of digital audio.

Manually configuring this system to have a DMA value of 330,000 and a scrub value of 20 produced the same results: an unstable system.

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SUBSTΓΓUTE SHEET (RULE 26) COMPARATIVE EXAMPLE II

A system built from a Tyan Tomcat 3 motherboard model 1563D with a socket 7 Intel HX 430 chipset, a Cyrix P150+ (according to Intel the P150+ operates at the same clock speed as the Intel 120 MHz Pentium of the Compaq Presario) with an internal cache of 512K, and 48 MB of RAM installed on the motherboard.

The system had a 3.8 GB fast ATA-2 EIDE hard drives which was partitioned into 5 logical drives, one (499 MB) containing the system and application files, three (546 MB) containing only MIDI and *.WAV files, and one (1.49GB) containing mixed and edited audio files. The operating system, Windows 95 and a copy of Cakewalk Pro version 5.0, Adaptec's 10 Easy CD Pro 95 and Adaptec Direct CD were installed on the logical drive containing the system and application files.

An Avid ROM 12S31 video card connected to an SVGA monitor and an Audiotrix DXG sound card sold by Mediatrix (variously connected to speakers, a mike, and MIDI devices) were installed in the system as was a CD-ROM reader. Connected to an installed SCSI controller was a Ricoh MediaMaster CD-RW MP6200S dual function rewritable-recordable CD recording drive.

The wave profiler (the auto-configuration aspect of the Cakewalk program) established a DMA of 4096 for this system. Using this system with the 4096 DMA value, and recording at a 44J Hz sampling rate, up to 6 tracks of digital audio could be temporally processed. However, in less than about 30 minutes of operation, the system invariably froze.

The Cakewalk manual recommended a DMA setting of 11J00. Using the 11J00 DMA value, and recording at a 44J Hz sampling rate, up to 16 tracks of digital audio could be temporally processed. However, after less than 15 minutes of operation, the system invariably froze. Increasing the DMA value to 22,400 produced substantially the same results as the

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SUBSTΓΓUTE SHEET (RULE 26) 11,200 DMA value: an unstable system that invariably froze.

Changing the scrub value from the Cakewalk recommended value of 100 to 20 produced substantially the same results.

Other default values were used including the following: No offset buffers;

A polyphony setting all that least about 24; A que buffer value of about 20; and A freeze frame setting of about 20. EXAMPLE I Using the system of COMPARATIVE EXAMPLE II, but manually setting the DMA value to 30,000 produced a system that has processed more than 70 tracks of digital audio at a sampling rate of 44 J MHz and operated for days without becoming unstable. This system was operated with a scrub value of 20.

Other default values were used including the following: No offset buffers;

A polyphony setting all that least about 24; A que buffer value of about 20; and A freeze frame setting of about 20. While the invention has been illustrated and described as embodied in an improved recording device and method, it is not intended to be limited to the details shown, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details -of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various

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SUBSTΓΓUTE SHEET (RULE 26)

Claims

applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

What is claimed is: 1. A recording system capable of substantially concurrently processing at least 16 tracks of

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SUBSTΓΓUTE SHEET (RULE 26) digital audio comprising: a personal computer having a Cyrix class CPU having a clock speed of at least about 75 MHZ, said personal computer configured in a conventional manner comprising the following components to: at least 2 logical data reservoirs; video hardware; a video display device functionally connected to said video hardware; sound hardware; an audio input device of functionally connected to said sound hardware; a mastering unit with functionally connected controller hardware; at least about 32 MEG RAM; a Windows operating system; a software recording application effective to record audio data files on a master media in said mastering unit; and a software application effective to process audio data files, said software application effective to process audio data files configured to have a DMA value of at least about 25,000.

2. The recording system of claim 1 in which said DMA value is less than about 3 3 5,000.

3. The recording system of claim 1 comprising at least about three logical data reservoirs.

4. The recording system of claim 3 in which each of said logical data reservoirs' has a storage capacity about least about 450 MB.

5. The recording system of claim 4 in which said personal computer operating system is configured to have all of its application software installed on a first logical data reservoir and all of its audio data files stored on a second logical data reservoir.

6. The recording system of claim 3 further comprising a high quality audio data reader. 7. The recording system of claim 1 wherein said Windows operating system is not Windows NT.

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SUBSTΓΓUTE SHEET (RULE 26)

8. The recording system of claim 1 wherein said personal computer comprises at least two Cyrix class CPUs.

9. The recording system of claim 1 having between about 3 and 48 digital audio inputs.

10. The recording system of claim 1 having at least about 48 MEG RAM. 11. The recording system of claim 1 wherein said recording system is portable.

12. The recording system of claim 11 wherein said recording system occupies of volume of less than about 1700 cubic inches.

13. A method of recording audio input on to a playable media comprising the steps of: activating a mobile recording system comprising at least one Cyrix class CPU with a Windows operating system having a plurality of logical storage drives, at least one of said logical storage drives having been designated for audio data files and substantially free of any application files; activating on said mobile recording system a software application effective to process audio data files; inputting an audio signal into said mobile recording system for processing by said software application effect to process audio data files; storing said processed audio data files on said logical storage drive designated for audio data files; mixing at least about 16 audio data files located on said logical storage drive designated for audio data files; and recording said mixed audio data files on a playable media.

14. The method of recording audio input of claim 13 wherein said mixing step comprises mixing at least about 24 audio data files.

15. A recording system capable of substantially concurrently processing at least 16 tracks of digital audio comprising:

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SUBSTΓΓUTE SHEET (RULE 26) a personal computer having a Cyrix class CPU having a clock speed of at least about 75 MHZ, said personal computer configured in a conventional manner comprising the following components to: at least 2 logical data reservoirs, the first of said logical data reservoirs being configured to contain substantially all of the operating and application software and substantially none of the audio data files installed on said s stem and the second of said logical data reservoirs being configured to contain substantially all of the audio data files and substantially none of the operating and application software installed on said system; video hardware; a video display device functionally connected to said video hardware; sound hardware; an audio device of functionally connected to said sound hardware a mastering unit with functionally connected controller hardware; at least about 48 MEG RAM a Windows operating system; a software recording application effective to record audio data files on a master media in said mastering unit; and a software application effective to process audio data files, said software application effective to process audio data files configured to have a DMA value between about 25,000 and 35,000.

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