DSP Xover project (part 2)

When I solve the HD powering issue, I'll be in the position of posting a step-by-step tutorial for those who'd like to try but haven't yet, if there's interest for that. I think it's a cool and funny project.

For a test you should be fine with an USB stick. USB HD's with power supply are also fine so as solid state disks should be. For HD's without power supply you must use a powered hub. To play from a network share is also no problem by wlan or wired net.
 
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Travelbug,

You win!!! I'll have to buy a Pi now... It seem to be a squeezebox crusher.

One question, Did you make a direct comparison with Volumio and piCorePlayer?? Could there be a winner??? I will probably try both and let my ear decide.

Also could one of those setup handle DSD files???

Thank you
 
Travelbug,

You win!!! I'll have to buy a Pi now... It seem to be a squeezebox crusher.

One question, Did you make a direct comparison with Volumio and piCorePlayer?? Could there be a winner??? I will probably try both and let my ear decide.

Also could one of those setup handle DSD files???

Thank you
PiCorePlayer is an option if you have a running Squeezebox system because it implements a very basic system with a squeezelite player. Advantage: fast boot and does not need a shutdown when switched off. Disadvantage: needs a Logitech media server. Volumio runs stand alone but I have no experience with it. Another option can be a media center on the Pi (RaspBMC, OpenELEC). This can also run a squeezelite player in the background if somebody needs the squeezebox option but also can playback audio and video up to full HD. Native DSD is possible with Volumio and I don't doubt with with squeezelite (piCorePlayer) too but I did not check it because I don't have such files. Native 96khz flacs are no problem.
 
Conclusion:

Standalone I would opt for Volumio. I just read that it has also a network multi room option.

If you have a running media server with some power (some NAS can do it too but can be sluggish in database performance) a Logitech media server is a nice option because there are some other nice (used - because Logitech stopped the hardware production) devices like the radio or the Boom box for the garden or terrace. But you can also run a Pi on batteries (<3 Watt) and connect it to your good old ghetto blaster :D . I've seen lithium ion packs for the pi. That should work with Volumio too.

Multimedia wise the XBMC brands for the Pi (RaspBMC, openELEC) do a good job with some more options to fiddle around with like surround playback via HDMI in addition to the high quality stereo with Najda.
 
IR Support

Eventually I've got the IR sensor working :). Some days ago I killed one because I used a wrong pinout so guys beware: There are different pinouts for the TSOP... types.


@chaparK Is it possible to add the switches commands to the IR commands? The small Apple remote has all buttons I need for configuration (up, down, right, left, set, menu). The play/stop command could be either used for mute or on/off.
 
Eventually I've got the IR sensor working :). Some days ago I killed one because I used a wrong pinout so guys beware: There are different pinouts for the TSOP... types.


@chaparK Is it possible to add the switches commands to the IR commands? The small Apple remote has all buttons I need for configuration (up, down, right, left, set, menu). The play/stop command could be either used for mute or on/off.

which ir sensor are you using? Is it different type respect the recommended?
V
 
Any chance you could comment on the projected size of this? I assume it will be quite small. I will leave space on my current build on the chance I may add this.

I second this Nick, please give us the design of the rear face !

I'll post the info by end of this week. I expect to have the expansions ready to ship (and of course supported in firmware/software) some time in March.

No, I have a TSOP38238 but it has a different pinout than eg. the other recommended TSOP39338. It will not kill Najda but the sensor.

Eventually I've got the IR sensor working :). Some days ago I killed one because I used a wrong pinout so guys beware: There are different pinouts for the TSOP... types.

Yes, indeed. Sometimes the only difference between 2 Vishay's references is just the pinout. Always check carefully the documentation of that precise part that you have purchased (applies also to LCDs, I2S expansions, rotary encoders etc ;) ).
Otherwise glad to read the problem is fixed now.

Is it possible to add the switches commands to the IR commands? The small Apple remote has all buttons I need for configuration (up, down, right, left, set, menu). The play/stop command could be either used for mute or on/off.

We could do this, but I'm afraid you don't have enough buttons on the Apple remote for that. The menu management requires 6 switches (4 directional + Set + Menu/Escape). That leaves you with a single button available...

Also, is that really something we'd want? For example, if you want another source now, you just assign that source to a switch on your remote and it's done.
If you emulate the menu on the remote, you need to:
- Press to enter the menu
- Press x times to get the source you want
- Press again to validate the selected source
... ?
 
Also, is that really something we'd want? For example, if you want another source now, you just assign that source to a switch on your remote and it's done.
If you emulate the menu on the remote, you need to:
- Press to enter the menu
- Press x times to get the source you want
- Press again to validate the selected source
... ?
It's just an option to remove the buttons on the front panel. With that, a stand by button and an encoder with switch you'd have all to control the whole thing. The encoder switch can be used for the mute function.
 
Hi,
I tried som FIR phase correction in front of Najda. It was hard to produce a good filter With rephase so I measured Acoustic phase at 1 meter and used this in Acourate. The red trace is Najda only and blue is Najda with fir frontend.

I have to make some switching possibility to compare with and without phase correction.

Nick,
do you know how many taps we can expect?
Will it be in the input section? (2-channels in front of IIR?)

best,
Paal
 

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The great thing about the Rpi is that it is so flexible GPIO wise. Even with I2S out, an IR receiver, some buttons AND a 9-pin ili9341 spi display connected, there's still a few gpios/uart and even an i2c bus free! Now, how'bout that i2c Najda uC control Nick? :)

I need more time until I can make this available. If you're coming with something implemented on the rPi that's already doing something, that's surely going motivate me to raise the priority of this task ;)

Hi,
I tried som FIR phase correction in front of Najda. It was hard to produce a good filter With rephase so I measured Acoustic phase at 1 meter and used this in Acourate. The red trace is Najda only and blue is Najda with fir frontend.

I have to make some switching possibility to compare with and without phase correction.

Nick,
do you know how many taps we can expect?
Will it be in the input section? (2-channels in front of IIR?)

best,
Paal

Hi Paal,

The FIR part of the mix will indeed come in the input section - so basically it's going to work similarly to your current setup with Acourate.
If you have questions on how to use rePhase, you should probably post them in the dedicated rePhase thread. I'm sure someone there can help you.
The number of available taps will depend on your sampling frequency and on the use you make of the IIR section. If you give me this info along with the DSPs load, then I can let you know how many approximately.

Nick
 
So from this picture I found:

An externally hosted image should be here but it was not working when we last tested it.



Your device's Data Out = P9/28 ( SP_1_CS0 )

Your device's FSync (or L/R) = P9/29 ( SP_1_DO )

Your device's SCLK (or BCLK) = P9/31 ( SPI_1_SLCK )

Thanks :)

Edit: I realise this is somewhat OT but if it works good it will take place in the dsp cabinet so......
 
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