TOPIC:

What would be most useful for me is having the ability to output the audio to the DAC via USB, then have the dac able to understand the volume position of the host system be it windows, mac or linux / android and adjust the loudness contour based on that. I run an Nexus 7 android tablet in my car, so that would make my life much easier.

Lots of ideas! For optimum fidelity, I would love for the loudness function to be calibratible to a certain flat volume level while having FIR filter to keep phase flat at 0, while also maintaining this phase response regardless which volume setting it used with the loudness curve. This should be a good technical challenge! Perhaps just volume determined multiple FIR filters?

From a device point of view, I am set to try hooking a TPlink blue tooth audio receiver to the 2x4HD, this seems to allow for selection between either wired or wireless input.

Still thinking out loud... What about a loudness plugin for the 2x4HD? Analog/Digital I/O plus FIR. I like the idea of FIR linear phase loudness control. That would be awesome.

Dedicate the 2x4HD to loudness. Eliminate compression, EQ, Delay and all other effects if necessary. Create banks for Linear FIR loudness curves and Minimum Phase IIR curves. Option for both would be nice. User creates an individual loudness curve and then sets the volume level where that curve is 100% active. Then they create the next curve in another bank and set the volume where that curve is active, and so on.

The 2x4HD will serve as the volume control for the system. As the volume is increased or decreased, the 2x4HD would fade between curves if between the setpoint of 2 curves. I'm not sure if a volume control with loudness with FIR exists on the market, but if this could be implemented that would be the ultimate. Linear phase customizable loudness control. Then create some presets so that different banks of loudness could be selected. This would be good for car audio. I could have loudness curves for engine on or engine off, etc.

The SHD added the display, streamer, and digital outputs which resolves many of the longstanding wishes for a all-in-one product. Thanks @devteam for listening to customers! Keeping my fingers crossed for loudness controls : )

Loudness on SHD when?

Perhaps with SHD mk II?

1. Basically a DDRC-98DA (9 inputs [ONE input EXCLUSIVELY mapped for dedicated calibrated Mic input], 8 outputs)
2. At least Six SHARC chips.
3. Ample DSP power to do whatever you want to in the digital domain.
4. A removable (maybe optional?) streamer module.
5. A dedicated network interface for the device which can be easily terminated into wireless/wired connections that will share it's connection to the (optionally?) plugged streamer unit.
6. One DSP chip for DIRAC processing
7. One DSP chip Matrix mixer and Crossover
8. One DSP chip for EQ, lots and lots and lots and lots of parametric EQ bands per channel
9. One DSP chip for the dynamic loudness
10. One DSP chip for Compressor, especially many many instance of multiband compressor can be made per-input/output channel
11. One DSP chip for Reverbs, and whatever you want to do, open the platform for 3rd party plugin developer ?!?!?!?!?

Honestly, this reminds me of Sonic Core's Scope Platform with it's crazy array of SHARC DSPs... Hahahaha.

By doing this, miniDSP can start selling add-on software compressors, reverbs, EQs, and many many more plugins (starting to sound eerily similar to Universal Audio) to fund the development of even crazier hardware for (from normal - to mildly crazy - to those who "went bananas") enthusiasts !!
OMG, I'm salivating...

The product will be split into 4 product lines:

1. Basic (costs around 1500 USD) - comes with only 3 DSP chips, limited inputs and outputs, does what the current SHD does but with the added dynamic loudness, cannot install 3rd party plugins, 1U enclosure
2. Advanced (costs around 1800 USD) - comes with 5 DSP chips, full array of inputs and outputs (excluding the dedicated calibrated Mic input), compressors, EQs, and capable of installing the 3rd party plugins, 2U enclosure
3. Ultimate (costs around 2500 USD) - the full experience, full inputs and outputs, dedicated calibrated Mic input for real-time dynamic loudness with the mic feedback loop for more accurate dynamic DSP processing, 2U enclosure with premium finish?
4. Developer (costs around 3000 USD) - all the Ultimate can do, with a license to develop plugins for the miniDSP platform, 2 extra DSP chips and a dedicated developer channel, connected to the internal developers for fast plugin incubator programs, 2U enclosure with premium finish

I'd take the Developer line in a flash and I think the rest of the product line will be INTERESTING enough to be used, either standalone - or with other miniDSP products

Damir.

As I type this. I am manually EQing the loudness curve on a 2x4 HD to compensate for loss in Bass/Treble at lower volumes
I was wondering if any progress was made on the loudness curve implementation?
it could just be a simple multiplier to the gain of an eq filter with a checkbox.

The eq gain would have the optional loudness multiplier thats linked to master volume.
Sorry for a bit convoluted explanation, I do image processing for a living and thought how I would approach this in my own domain.
Ofcourse this relatively simple math could be quite different to implement on hardware but throwing some ideas.

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loudness compensation setup(via the plugin)

Inputs:
-MV(Current Master Volume)
-MVh(Master Volume High cutoff: User defined)
-MVl(Master Volume Low cutoff: User defined)
-Exp(power exponent to implement a non-linear curve if needed: User defined)

Loudness Multiplier = Pow[Clamp[(MVh-MV)/(MVh-MVl)], Exp]

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# Clamp[] : clips the output between 0 and 1
# Pow[a,b] : a raised to the exponent power b

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Thank you for reading.

Sure do. I would also love to see a "Loudness setting

The exponent seems a bit difficult to control but why not have the linear interpolation between two correction curves?
That would be very easy to control and computation costs are controllable as well based on the amount of allowed peqs.
Would be fantastic to have on the 2x4 hd.
 


 

Got a monoprice HTP-1 with Dirac that has a loundness curve.  It sounds so much better than my SHD at low to normal listening volumes.  You can come up with different SHD dirac curves with the bass boosted but it's not the same. 

I would just like to add my +1 to this request. In my head the perfect implementation of this would be to have a user configurable set volume point where the full loudness eq curve was deployed (for example -30dB and down) and another set point where it was completely off (for example -10dB and up) and between these set points the eq would be gradually applied. 
My Clarion car stereo head unit over 20 years ago had a DSP with volume adjusted loudness and I still miss it Should be a relatively low hanging fruit with the SHD´s fantastic DSP?