Re: [LAU] Small instrument hardware module

On Wed, October 22, 2014 10:06 pm, Leonardo Gabrielli wrote:
>
> On 22/10/2014 11:45, linux-audio-user-request@email-addr-hidden wrote:
>> In my experience there's a greater risk of overheating without a fan and
>> the ARM (allwinner) chipsets are prone to that. My bet is a low power
>> x86
>> processor/unit with a (quiet) fan will out perform and outlast an ARM
>> chipset without.
> I did some simple benchmarks on a Allwinner A20 board (cubieboard)
> recently. The benchmark consist of computing a bunch of sine oscillators
> (second order resonator filter), generally used for modal synthesis and
> other types of sound synthesis. The results I got from the A20 when
> clocked at 1GHz are suprisingly good: 1000 theoretical oscillator can be
> computed in a 128 samples period, while on my quad core-i5 I get 1500.
> On a 7-years onld Centrino Duo I get about 850. While this don't stand
> as a real-world benchmark (buffer transfers are not taken into account)
> and I haven't optimized for the architectures (but just let g++ go with
> -O2) you get the idea.
>
> I didn't experience overheating on the A20 but the tests are not
> continuous as you would during a performance, so I won't bet it will
> last long. :)
>

I have been working with a20's for about a year and the biggest problem we
have is overheating. However that can be associated with a number of
design decisions so I can't blame the a20's entirely. I have observed that
they always run hot unless they are put into standby mode.

> I have a sensation that generally the kernel is also quite unstable on
> most platforms unless a silicon manufacturer is there to help (as it
> happens with some TI chips) and in general I would prefer Intel for
> reliable live performance. However as a researcher I am trying to
> squeeze ARMs to perform as musical instruments and I think they can work
> well if the industry supports kernel development. But I'm wondering if
> this will continue to happen, since the eastern mobile market is
> crushing the sales of the reliable manufacturers.
>

Allwinner have recently joined up to the Linaro consortium so that bodes
well for their future offerings in regards to standardising on kernel
support. FWIW, I have found that their customer service dept is completely
useless but if you get in touch with their developers directly they are
very helpful and knowledgable.

> Going slightly OT: I really hate how the market is pushing on short
> products lifecycles, following the trend of the mobile industry. On one
> side the audio and music market is similar to the consumer market as
> users want to have ever new and fancy products with appeal. On another
> side it is similar to the industry/autmotive market as you need reliable
> products that last for years. What you should find inside is sturdy
> electronics with a support of >10 years and the possibility to find new
> pin-compatible ICs after those 10 years from the manufacturer. There's
> too much consumerism in the silicon industry following the mobile
> "revolution" meaning that everything contains electronics is destined to
> last less and die shortly. Or enter the market in pre-beta stage (which
> nowadays is considered a "feature"). The only way to get long term
> support is sticking to the old good silicon manufacturers, hoping they
> won't discontinue your MCU/CPU/DSP soon (as they are doing to cut costs).
> I hope someday people will realize that not all electronic products are
> like smartphones.
>

You might want to look at the microchip range. They are bringing back the
old school attention to the vendor that many chipset manufacturers have
abandoned these days. They support android on some of their line and also
provide an open source RTOS which they develop in house. They are also in
the process of supporting a bunch of Linux distro's.

We have tested their PIC32 line and found them to be extremely well
designed with the attention on the things that matter as priority. However
they are not as advanced in the software department as ARM offerings but
they do provide excellent support to make up for that.

--
Patrick Shirkey
Boost Hardware Ltd
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