Audio Improvements

Hi everyone,

Is there anywhere I can get a list of improvements to the RISC OS 5 sound system? without having to read through the massive threads on here…

Most importantly I would like to know if the issue with crackling sound on the Iyonix has been fixed? (see http://www.drobe.co.uk/article.php?id=1438&hlt=iyonix if you don’t know the issue I’m talking about)

I’m thinking about buying a second hand Iyonix and want to use if audio playback so any info would be gratefully received…

Thanks in advance,

Lee

The basic problem with the Iyonix hardware is that the hardware clocks samples at 48k whatever sample rate you specify/play/capture. This means samples are simply repeated or skipped to fit. The result is poor quality unless you use 48k. And the hardware also clips the largest samples. So even 48k is less than ideal.

If you want good quality audio from an Iyonix, see the threads, etc, on USB audio and consider using an external USB audio device. That way you can get results as good as with Linux/Windows/Macs. Even a Behringer UCA202 (about 20 quid) used with an Iyonix will give far better results (and let you record well).

Jim

And for 50 quids, what can we use? :)

So if I use a USB audio adaptor with the correct drivers will all the sound output be played through it? ie if I playback an Mp3 with DigitalCD will the output go through the USB soundcard?

And for 50 quids, what can we use? :)

Not sure about 50. For recording, I’m currently using a Scarlett 2i2 which is just over a hundred quid but does 96k/24. I put details of what I’ve used or tested here

http://www.audiomisc.co.uk/HFN/ADC/USBrecording.html

CJE I think have the UCA202. They may also now stock the 2i2 but I bought mine from 247 com.

For replay I’m using a Cambridge Audio Dac Magic Plus. This delivers excellent results, as good as you’d get with ‘other operating systems’ (ahem!). ;→ This does cost more than 50 quid, but puts the results into the serious hifi quality range, though.

This all works with my Iyonix as well as with my ARMiniX.

So if I use a USB audio adaptor with the correct drivers will all the sound output be played through it? ie if I playback an Mp3 with DigitalCD will the output go through the USB soundcard?

Problem there I’m afraid. At present the only software that can play or record via USB works only with wave files. Not mp3. At present the established apps like DCD or PlaySound can’t send their output to USB. I and some other people have developed some player/recorder software that uses the USB devices. But DCD/PlaySound haven’t taken this new ability on as yet. USB Audio is a relatively new development for RO.

However you don’t need a ‘driver’. You do need a USB device that works using the USB audio device ‘class’ 1 or 2 standards. There are a number of these. You then just load the modules developed by Colin Granville and Dave Higton.

Jim

Quite pricey hardware, but very interesting informations. Thanks.

I think the UCA202 is only about 20 – 30 quid. Which seems pretty reasonable given what it does. I’ve just been told the Behringer XENYX 1024 also works, but as yet I don’t know anything else about it!

There are also a number of other cheaper devices which will probably work. The problem is being able to check them and find out. Retailers and even makers seem not to say in many cases.

A couple of days ago I told Focusrite their 2i2 worked nicely with Linux and RO and asked them to let me know if any of their other devices followed the USB ‘audio class’ standards. The response was simply “we don’t support Linux or RO”. …which didn’t actually deal with my question.

I pointed out that millions of people have bought RPi’s and that runs Linux and RO not Windows or Mac. So maybe they should know the answers to such questions and let people know. Maybe even ensure their kit does where it doesn’t. But many makers/dealers seem to have a real blind spot about such matters, alas. They seem unable to grasp that they don’t have to “support” Linux or RO if they just follow the standards and can say so. So even when they do make devices that will work, they can’t say. Weird given the potential market share they’re ignoring these days.

Jim

…which didn’t actually deal with my question.

Dear Sirs, from the behaviour when connected to my hardware your 2i2 unit appears to conform to USB audio class standards, can you confirm that other products in your USB audio product range behave in a similar way?
Could you highlight the USB control for any additional features in other units?

No mention of any OS or any proprietary drivers that might be in any specific OS

FWIW I made my comment re the RPi, etc, to them after they’d replied to my question. I’m baffled by makers who fail to see a potential market like that. However…

I suspect the only way we’ll get makers to deal with this is when they see that one of them is selling in decent amounts to people who specify they rely on the relevant USB standards. In the past that’s put us in a ‘chicken and egg’ situation, but maybe the RPi will change this in time.

Whatever, it seems mad to me that makers don’t say in the equipment handbooks, and either ignore or duck the question even when their devices DO work in accord with the standards.

Of course, this can work against Windows users as well given the problems that OS-specific drivers bring. But at least they are habituated to every ‘computer’ item they buy probably becoming ‘obsolete’ within a few years. So I guess they just curse and accept it like the weather. :-}

From my POV I’d be happy to test candidate devices and list the ones that work. The problem is that I’m not going to buy every possible candidate only to find I’m spending money on many that don’t work.

Jim

Whatever, it seems mad to me that makers don’t say in the equipment handbooks, and either ignore or duck the question even when their devices DO work in accord with the standards.

Not really. Depending on the standard in question, there’s a world of difference between making your product comply with the standard and stating that your product complies with the standard. The former requires a copy of the standard and care when developing your product. The latter could well require expensive test systems or off-site accreditation, plus lots of development time to fix obscure edge cases that 99.99% of your customers will never see.

The question then is whether the sales to Linux and/or RISC OS users will cover the costs of that extra investment, plus a useful profit margin. Given the size of the Windows market compared to that of Linux plus RISC OS combined, selling the hardware along with dedicated software for Windows is likely to win out many times over.

And again, depending on the standard body concerned, even saying to a customer that you believe product X “should follow the standard, but we haven’t confirmed that” could get you into a lot of legal hot water if said customer finds one of those edge cases and then complains to the standard’s originating body with some evidence of your original communication to them.

Depending on the standard in question, there’s a world of difference between making your product comply with the standard and stating that your product complies with the standard. The former requires a copy of the standard and care when developing your product. The latter could well require expensive test systems or off-site accreditation, plus lots of development time to fix obscure edge cases that 99.99% of your customers will never see.

Actually, the reality is probably more likely to be that most makers will be using one of the common USB interface ICs which has been built to follow the standards. And so far as I know, you don’t have to pay the USB Forum to use the standards or validate, to say you’re using them.

Again the reality is that various makers say things like the device is/uses USB 1 or USB 2. Which could easily lead buyers to assume that meant the same as Audio ‘Class’ 1 or 2. So they may get complaints anyway for not following the standards. I suspect they then give the reply they’d give anyway. “Its OK here. Must be something wrong at your end.”

But I do realise that many makers may think as you describe.

Add to that: To be specific. When I first tried USB DACs from Cambridge Audio they were interested to see what results I got to check out that the devices they sent me did work using the standard methods. And they modified some test devices to sort out initial problems. Their POV was that it helped them check the kit would work reliably with Windows and Macs as well as other OSs. So this comes down to a question of attitude I think.

If they wanted to duck responsibility or the work, they could also allow someone else – e.g. me in some cases – simply to try one on loan and report on it. Makers do send out kit for reviews for that very reason. Then they could reply, “We can’t say for sure, but judge for yourself given the review(s)” and give a relevant URL or whatever. But although some makers do this, others won’t. Again, I think this comes down to their mindset.

Obviously, its their choice in the end. But it stills seems crazy to me to rebuf what has become a steadily larger potential market. Its not as if the RPi has had no publicity about the sheer scale of its success, for example.

Jim