[mirror_ubuntu-bionic-kernel.git] / Documentation / sound / cards / emu10k1-jack.rst

=================================================================
Low latency, multichannel audio with JACK and the emu10k1/emu10k2
=================================================================

This document is a guide to using the emu10k1 based devices with JACK for low
latency, multichannel recording functionality.  All of my recent work to allow
Linux users to use the full capabilities of their hardware has been inspired 
by the kX Project.  Without their work I never would have discovered the true
power of this hardware.

	http://www.kxproject.com
						- Lee Revell, 2005.03.30


Until recently, emu10k1 users on Linux did not have access to the same low
latency, multichannel features offered by the "kX ASIO" feature of their
Windows driver.  As of ALSA 1.0.9 this is no more!

For those unfamiliar with kX ASIO, this consists of 16 capture and 16 playback
channels.  With a post 2.6.9 Linux kernel, latencies down to 64 (1.33 ms) or
even 32 (0.66ms) frames should work well.

The configuration is slightly more involved than on Windows, as you have to
select the correct device for JACK to use.  Actually, for qjackctl users it's
fairly self explanatory - select Duplex, then for capture and playback select
the multichannel devices, set the in and out channels to 16, and the sample
rate to 48000Hz.  The command line looks like this:
::

  /usr/local/bin/jackd -R -dalsa -r48000 -p64 -n2 -D -Chw:0,2 -Phw:0,3 -S

This will give you 16 input ports and 16 output ports.

The 16 output ports map onto the 16 FX buses (or the first 16 of 64, for the
Audigy).  The mapping from FX bus to physical output is described in
sb-live-mixer.rst (or audigy-mixer.rst).

The 16 input ports are connected to the 16 physical inputs.  Contrary to
popular belief, all emu10k1 cards are multichannel cards.  Which of these
input channels have physical inputs connected to them depends on the card
model.  Trial and error is highly recommended; the pinout diagrams
for the card have been reverse engineered by some enterprising kX users and are 
available on the internet.  Meterbridge is helpful here, and the kX forums are
packed with useful information.

Each input port will either correspond to a digital (SPDIF) input, an analog
input, or nothing.  The one exception is the SBLive! 5.1.  On these devices,
the second and third input ports are wired to the center/LFE output.  You will
still see 16 capture channels, but only 14 are available for recording inputs.

This chart, borrowed from kxfxlib/da_asio51.cpp, describes the mapping of JACK
ports to FXBUS2 (multitrack recording input) and EXTOUT (physical output)
channels.

JACK (& ASIO) mappings on 10k1 5.1 SBLive cards:

==============  ========        ============
JACK		Epilog		FXBUS2(nr)
==============  ========        ============
capture_1	asio14		FXBUS2(0xe)
capture_2	asio15		FXBUS2(0xf)
capture_3	asio0		FXBUS2(0x0)	
~capture_4	Center		EXTOUT(0x11)	// mapped to by Center
~capture_5	LFE		EXTOUT(0x12)	// mapped to by LFE
capture_6	asio3		FXBUS2(0x3)
capture_7	asio4		FXBUS2(0x4)
capture_8	asio5		FXBUS2(0x5)
capture_9	asio6		FXBUS2(0x6)
capture_10	asio7		FXBUS2(0x7)
capture_11	asio8		FXBUS2(0x8)
capture_12	asio9		FXBUS2(0x9)
capture_13	asio10		FXBUS2(0xa)
capture_14	asio11		FXBUS2(0xb)
capture_15	asio12		FXBUS2(0xc)
capture_16	asio13		FXBUS2(0xd)
==============  ========        ============

TODO: describe use of ld10k1/qlo10k1 in conjunction with JACK
Commit	Line	Data
e7030c96 TI	1	=================================================================
	2	Low latency, multichannel audio with JACK and the emu10k1/emu10k2
	3	=================================================================
	4
9c220a31 LR	5	This document is a guide to using the emu10k1 based devices with JACK for low
	6	latency, multichannel recording functionality. All of my recent work to allow
	7	Linux users to use the full capabilities of their hardware has been inspired
	8	by the kX Project. Without their work I never would have discovered the true
	9	power of this hardware.
	10
	11	http://www.kxproject.com
	12	- Lee Revell, 2005.03.30
	13
9c220a31 LR	14
	15	Until recently, emu10k1 users on Linux did not have access to the same low
	16	latency, multichannel features offered by the "kX ASIO" feature of their
	17	Windows driver. As of ALSA 1.0.9 this is no more!
	18
	19	For those unfamiliar with kX ASIO, this consists of 16 capture and 16 playback
	20	channels. With a post 2.6.9 Linux kernel, latencies down to 64 (1.33 ms) or
	21	even 32 (0.66ms) frames should work well.
	22
	23	The configuration is slightly more involved than on Windows, as you have to
	24	select the correct device for JACK to use. Actually, for qjackctl users it's
	25	fairly self explanatory - select Duplex, then for capture and playback select
	26	the multichannel devices, set the in and out channels to 16, and the sample
	27	rate to 48000Hz. The command line looks like this:
e7030c96	28	::
9c220a31	29
e7030c96	30	/usr/local/bin/jackd -R -dalsa -r48000 -p64 -n2 -D -Chw:0,2 -Phw:0,3 -S
9c220a31 LR	31
	32	This will give you 16 input ports and 16 output ports.
	33
	34	The 16 output ports map onto the 16 FX buses (or the first 16 of 64, for the
	35	Audigy). The mapping from FX bus to physical output is described in
e7030c96	36	sb-live-mixer.rst (or audigy-mixer.rst).
9c220a31 LR	37
	38	The 16 input ports are connected to the 16 physical inputs. Contrary to
	39	popular belief, all emu10k1 cards are multichannel cards. Which of these
	40	input channels have physical inputs connected to them depends on the card
	41	model. Trial and error is highly recommended; the pinout diagrams
	42	for the card have been reverse engineered by some enterprising kX users and are
	43	available on the internet. Meterbridge is helpful here, and the kX forums are
	44	packed with useful information.
	45
	46	Each input port will either correspond to a digital (SPDIF) input, an analog
	47	input, or nothing. The one exception is the SBLive! 5.1. On these devices,
	48	the second and third input ports are wired to the center/LFE output. You will
	49	still see 16 capture channels, but only 14 are available for recording inputs.
	50
	51	This chart, borrowed from kxfxlib/da_asio51.cpp, describes the mapping of JACK
	52	ports to FXBUS2 (multitrack recording input) and EXTOUT (physical output)
	53	channels.
	54
e7030c96 TI	55	JACK (& ASIO) mappings on 10k1 5.1 SBLive cards:
	56
	57	============== ======== ============
9c220a31	58	JACK Epilog FXBUS2(nr)
e7030c96	59	============== ======== ============
9c220a31 LR	60	capture_1 asio14 FXBUS2(0xe)
	61	capture_2 asio15 FXBUS2(0xf)
	62	capture_3 asio0 FXBUS2(0x0)
	63	~capture_4 Center EXTOUT(0x11) // mapped to by Center
	64	~capture_5 LFE EXTOUT(0x12) // mapped to by LFE
	65	capture_6 asio3 FXBUS2(0x3)
	66	capture_7 asio4 FXBUS2(0x4)
	67	capture_8 asio5 FXBUS2(0x5)
	68	capture_9 asio6 FXBUS2(0x6)
	69	capture_10 asio7 FXBUS2(0x7)
	70	capture_11 asio8 FXBUS2(0x8)
	71	capture_12 asio9 FXBUS2(0x9)
	72	capture_13 asio10 FXBUS2(0xa)
	73	capture_14 asio11 FXBUS2(0xb)
	74	capture_15 asio12 FXBUS2(0xc)
	75	capture_16 asio13 FXBUS2(0xd)
e7030c96	76	============== ======== ============
9c220a31 LR	77
9c220a31 LR	78	TODO: describe use of ld10k1/qlo10k1 in conjunction with JACK