5 Jun
2013
5 Jun
'13
4:25 p.m.
hi *!
in case someone is looking for a similar problem solver:
i just received an esi gigaport hd+, which is a usb1 class-compliant,
bus powered audio interface that provides 8 discrete unbalanced audio
outs. at 135€, it's not quite a steal, but it solves one problem: to be
able to listen to 5.1/7.1 content with a laptop.
it works with jack out of the box and comes with two headphone outs, one
of which plays outs1/2, the other plays a pair-wise mix of all eight
outs. there is a row of flashing blue leds as "signal present"
indicators, although their threshold is a bit on the high side.
sound quality is appropriate, i gave it a quick listen and there is
nothing obviously wrong.
i bought it for use with a raspberry pi, which is the next thing i have
to try - will report back. for now & on my laptop, it runs fine at
124x4, haven't tried to push the latency down more, but since it only
has outputs, what's the point anyways?
best,
jörn
--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487
Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT
http://stackingdwarves.net
5 Jun
5 Jun
6:35 p.m.
On 06/05/2013 04:25 PM, Jörn Nettingsmeier wrote:
i bought it for use with a raspberry pi, which is the
next thing i have
to try - will report back.
works like a charm for now, at 512x4. i did manage to lose the main
filesystem once during my tests, but a reboot fixed it. can't say if
this is directly related to the USB device... might have been a power
issue - i'm not using a powered up, relying on the 1A mini-usb input
instead (which, according to the famous internet, should be ok on revB
models).
for the record, jack will of course require the patch to remove packed
structs, jeremy's repo works fine for me.
--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487
Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT
http://stackingdwarves.net
10:57 p.m.
On Wed, Jun 05, 2013 at 04:25:56PM +0200, Jörn Nettingsmeier wrote:
in case someone is looking for a similar problem
solver:
i just received an esi gigaport hd+, which is a usb1
class-compliant, bus powered audio interface that provides 8
discrete unbalanced audio outs. at 135€, it's not quite a steal, but
it solves one problem: to be able to listen to 5.1/7.1 content with
a laptop.
it works with jack out of the box and comes with two headphone outs,
one of which plays outs1/2, the other plays a pair-wise mix of all
eight outs. there is a row of flashing blue leds as "signal present"
indicators, although their threshold is a bit on the high side.
sound quality is appropriate, i gave it a quick listen and there is
nothing obviously wrong.
Interesting device... If and when you find the time, could you hook it
up to a Micstasy line input and Jaaa... ?
Ciao,
--
FA
A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)
6 Jun
6 Jun
1:32 p.m.
On 06/05/2013 10:57 PM, Fons Adriaensen wrote:
On Wed, Jun 05, 2013 at 04:25:56PM +0200, Jörn
Nettingsmeier wrote:
ok. now running on my laptop at 64x4 w/o xruns but at very low load.
for the measurements, i'm running off the battery to avoid hum issues,
but plugging it did not make any noticeable difference to me.
gigaport hd+ connected to a micstasy line in at normal Z (5.6kOhm
unbalanced) with a crappy rca to jack cable.
i chose 21.0dB amplification, because that should correspond to 0dBu at
full scale. indeed, it makes a -1.0dBFS sine wave from the gigaport come
out at roughly -14dBFS on the hdspm, which is what i'd expect going from
consumer (-10dBV) to pro equipment (+4dBu).
jnoisemeter reports -88.4 dB in flat mode with DC filter and slow
averaging response.
now if i feed it a white noise signal from JAAA at -1.0dBFS, the other
end reports a flat noise level of -13.1 dB, which as a rough guesstimate
gives us about 70dB of usable dynamic range. not great, but ok.
the -1.0dbFS sine tone at 1kHz shows a first harmonic at -95dB, and the
upper harmonics barely show in the noise, so we're fine here.
however, there is a thumping DC impulse every few seconds which clearly
shows up on the scope. it's clearly audible, not a show stopper, but
needs looking into. it's signal-dependent: when you don't generate a
sine-wave, it stops. complex signals either don't cause it or mask it
completely. might be a power issue. here's what it looks like (peak hold
and freeze, imagine this as a transient):
http://stackingdwarves.net/download/GigaportHD+%20Thumping%20noise%20over%2…
a white noise steady-state spectrum shows a slight raise of 2.5dB around
6khz, and another hefty boost of 3.5dB around 14khz.
so much for a quick run-through. if you want specific measurements or
have a pointer to proper measurement techniques, let me know.
best,
jörn
--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487
Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT
http://stackingdwarves.net
in case someone is looking for a similar problem
solver:
i just received an esi gigaport hd+, which is a usb1
class-compliant, bus powered audio interface that provides 8
discrete unbalanced audio outs. at 135€, it's not quite a steal, but
it solves one problem: to be able to listen to 5.1/7.1 content with
a laptop.
it works with jack out of the box and comes with two headphone outs,
one of which plays outs1/2, the other plays a pair-wise mix of all
eight outs. there is a row of flashing blue leds as "signal present"
indicators, although their threshold is a bit on the high side.
sound quality is appropriate, i gave it a quick listen and there is
nothing obviously wrong.
Interesting device... If and when you find the time, could you hook it
up to a Micstasy line input and Jaaa... ? 
2:13 p.m.
On 06/06/2013 01:32 PM, Jörn Nettingsmeier wrote:
On 06/05/2013 10:57 PM, Fons Adriaensen wrote:
some more measurements at
http://stackingdwarves.net/download/GigaportHD+/
--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487
Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT
http://stackingdwarves.net
On Wed, Jun 05, 2013 at 04:25:56PM +0200, Jörn
Nettingsmeier wrote:
ok. now running on my laptop at 64x4 w/o xruns but at very low load.
for the measurements, i'm running off the battery to avoid hum issues,
but plugging it did not make any noticeable difference to me.
gigaport hd+ connected to a micstasy line in at normal Z (5.6kOhm
unbalanced) with a crappy rca to jack cable.
i chose 21.0dB amplification, because that should correspond to 0dBu at
full scale. indeed, it makes a -1.0dBFS sine wave from the gigaport come
out at roughly -14dBFS on the hdspm, which is what i'd expect going from
consumer (-10dBV) to pro equipment (+4dBu).
jnoisemeter reports -88.4 dB in flat mode with DC filter and slow
averaging response.
now if i feed it a white noise signal from JAAA at -1.0dBFS, the other
end reports a flat noise level of -13.1 dB, which as a rough guesstimate
gives us about 70dB of usable dynamic range. not great, but ok.
the -1.0dbFS sine tone at 1kHz shows a first harmonic at -95dB, and the
upper harmonics barely show in the noise, so we're fine here.
however, there is a thumping DC impulse every few seconds which clearly
shows up on the scope. it's clearly audible, not a show stopper, but
needs looking into. it's signal-dependent: when you don't generate a
sine-wave, it stops. complex signals either don't cause it or mask it
completely. might be a power issue. here's what it looks like (peak hold
and freeze, imagine this as a transient):
http://stackingdwarves.net/download/GigaportHD+%20Thumping%20noise%20over%2…
a white noise steady-state spectrum shows a slight raise of 2.5dB around
6khz, and another hefty boost of 3.5dB around 14khz.
so much for a quick run-through. if you want specific measurements or
have a pointer to proper measurement techniques, let me know. in case someone is looking for a similar problem
solver:
i just received an esi gigaport hd+, which is a usb1
class-compliant, bus powered audio interface that provides 8
discrete unbalanced audio outs. at 135€, it's not quite a steal, but
it solves one problem: to be able to listen to 5.1/7.1 content with
a laptop.
it works with jack out of the box and comes with two headphone outs,
one of which plays outs1/2, the other plays a pair-wise mix of all
eight outs. there is a row of flashing blue leds as "signal present"
indicators, although their threshold is a bit on the high side.
sound quality is appropriate, i gave it a quick listen and there is
nothing obviously wrong.
Interesting device... If and when you find the time, could you hook it
up to a Micstasy line input and Jaaa... ?
10:57 p.m.
On Thu, Jun 06, 2013 at 01:32:08PM +0200, Jörn Nettingsmeier wrote:
gigaport hd+ connected to a micstasy line in at normal
Z (5.6kOhm
unbalanced) with a crappy rca to jack cable.
i chose 21.0dB amplification, because that should correspond to 0dBu
at full scale. indeed, it makes a -1.0dBFS sine wave from the
gigaport come out at roughly -14dBFS on the hdspm, which is what i'd
expect going from consumer (-10dBV) to pro equipment (+4dBu).
jnoisemeter reports -88.4 dB in flat mode with DC filter and slow
averaging response.
So dynamic range should be 88.4 - 13 or around 75 dB.
No really impressive...
now if i feed it a white noise signal from JAAA at
-1.0dBFS, the
other end reports a flat noise level of -13.1 dB, which as a rough
guesstimate gives us about 70dB of usable dynamic range. not great,
but ok.
That would be a really invalid measurement. Peak / RMS ratio for
jaaa's noise generator is something like 12dB, so noise at -1 dB
RMS will be clipping as hell. That 12 dB is an implementation
limit, real gaussian noise has (in theory) an infinite peak / RMS
ratio. So better stay at -20 dB RMS or so.
the -1.0dbFS sine tone at 1kHz shows a first harmonic
at -95dB, and
the upper harmonics barely show in the noise, so we're fine here.
OK.
however, there is a thumping DC impulse every few
seconds which
clearly shows up on the scope. it's clearly audible, not a show
stopper, but needs looking into. it's signal-dependent: when you
don't generate a sine-wave, it stops. complex signals either don't
cause it or mask it completely. might be a power issue.
Very suspect. Should be interesting to record the waveform and
have a look at it (zita-scope would be handy, but not yet ready
for the real world).
a white noise steady-state spectrum shows a slight
raise of 2.5dB
around 6khz, and another hefty boost of 3.5dB around 14khz.
Again suspect, but see above. Could you try with a lower noise
level ?
General remark about the Jaaa screenshots: to measure noise you
should really use the noise, not peak, markers.
Ciao,
--
FA
A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)
5 Jun
5 Jun
11:18 p.m.
On Wed, Jun 5, 2013 at 3:25 PM, Jörn Nettingsmeier <
nettings(a)stackingdwarves.net> wrote:
it runs fine at 124x4, haven't tried to push the
latency down more, but
since it only has outputs, what's the point anyways?
Live performance using MIDI input is a use case.. I'd be intrested what
latencies it can do if you wouldn't mind testing? One of 128 * 2, 128 *
3, 64 * 4 or 64 *3 would probably run best... 64 * 2 would be
amazing for the channel count though :D
On another topic, how would using 2 of these fare for WFS applications? It
would make the cheapest 16 output channel external soundcard that I know
of.. but I fear that the non-sample accurate sync would throw off source
perception?
6 Jun
6 Jun
1:36 p.m.
On 06/05/2013 11:18 PM, Harry van Haaren wrote:
On Wed, Jun 5, 2013 at 3:25 PM, Jörn Nettingsmeier
<nettings(a)stackingdwarves.net <mailto:nettings@stackingdwarves.net>> wrote:
here be plasma-breathing plutonium dragons with infrared laser eyes.
it runs fine at 124x4, haven't tried to push
the latency down more,
but since it only has outputs, what's the point
anyways?
Live performance using MIDI input is a use case.. I'd be intrested what
latencies it can do if you wouldn't mind testing? One of 128 * 2,
128 * 3, 64 * 4 or 64 *3 would probably run best... 64 * 2 would
be amazing for the channel count though :D
On another topic, how would using 2 of these fare for WFS applications? It would make the cheapest 16 output channel external
soundcard that I
know of.. but I fear that the non-sample accurate sync would throw off
source perception?
definitely.
rule of thumb: if you are considering WFS and the price of the
_interface_ is an issue, you don't really want to be doing WFS.
--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487
Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT
http://stackingdwarves.net
4217
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7 comments
3 participants
participants (3)
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Fons Adriaensen -
Harry van Haaren -
Jörn Nettingsmeier