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Hi Kids,

Dunno how many of you are using 2 nanoAVRs in a Full-Gonzo setup as I've described here. (I'd be really interested in hearing about it if you are!) But I had a brief bit of weirdness the other night that I thought I'd share, just in case.

I've recently purchased a Pioneer BDP-80FD Blu-Ray player, which is one of the recent units found to be "teachable" to rip SACDs to .iso files, which can then be played from Foobar2000, etc. As a result, I've been purchasing and enjoying lots of SACDs (mostly multichannel) over the last few months. (I'll leave the irony of this scenario for another discussion, heh.)

Anyway, I was listening to the reissue of the original quad mix of Jeff Beck's Wired album, when I noticed the balance was all messed up between the front & rear, Since I use one nano for front and the other for rear, I figured the IR remote volume settings had gotten out of sync between the units somehow. Sure enough, after booting up the laptop and looking at the plugins for the two units, they were off by several dB. This has been an extremely rare occurrence, as I've described in previous posts above.

Fortunately, the cure is simple enough: I just held the volume down button on the old Sony remote I use until both units' volume settings bottomed out at -123 dB or whatever it is, then back up to normal listening level, and every thing was fine. Until later in the evening when it happened again! Oh no, I thought. If these units have suddenly decided to not stay in sync anymore, I'm going to have to rethink the whole setup! What is going on here?

After a few minutes of head scratching, I finally discovered that the batteries in my remote were almost dead.

- Jim

Hi Jim

Not too many hardcore users like yourself it seems!
There is a great news though... Did you check out that we released a new app for android/IoS? It's called the "miniDSP Controller" and does support control for multiple nanoAVR/PWR-ICE unit. i.e. master volume control /preset sent to multiple "linked" units..

Pretty cool hey? Have a trial maybe?

DevTeam

I have tried the phone app, and I don't mean to sound ungrateful for your efforts there. It's just that in order to use it, I have to unlock my phone, switch to the app if it's not up, then work the virtual slider - a lot of steps just to change the volume. Much quicker and easier to just grab the remote and push a button - I don't even have to look at it. Also, the volume buttons on the remote give me a solid 1.5 dB change with each press - more accurate & predictable than the virtual slider in the app. Again, hardly any of this is the fault of your app. It's just the nature of the beast with Android and touch screens.

Dunno how old this thread is, but your use of nanoAVR HDAs is interesting. I am particularly interested if you find the DAC quality adequate.

I am also using two nanoAVRs but quite differently: I am daisy chaining them to do Dirac Live procesding in one and bass management in another in a 7.1 system. The output feeds an HDTV Supply HDMI to SDI converter from which I deembed 8 channels of digital audio on four AES3 lines that feed a Lucid 8824 8 channel DAC and then my amps. Works well.

I was wondering if the HDA DAC could hold its own against the Lucid 8824 with 105 db SNR and 0.017% THD. Some have said it is noisy.

Hi rhollan,

I have no gripes with the DACs in the nanoAVR-HDAs. There is some additional noise compared to the previous setup, as described in the top post of this thread (see: THE BAD), but it's really not a problem for me. As for sound quality, I think they sound lovely, and by that I mean they don't seem to have any sound of their own at all. I suppose it could be an issue with higher-gain power amps and/or high-efficiency speakers.

You mentioned the noise floor was up about 10 dB. Compared to WHAT?

I don't run hyper-efficient horn speakers: mine are 88 and 90 db/W/m. But I found AJA ADA-4 DACs with 95 dB SNR too noisy and a Lucid ADA 8824 at 105 db fine. I could probably live with the ADA-4s with some gain structure tweaking, but would rather not. I think a 100 dB SNR figure is about as poor as I could go for theatre duty.

rhollan wrote:

You mentioned the noise floor was up about 10 dB. Compared to WHAT?

Compared to the previous setup, where I was using dual Yamaha AVRs primarily for DAC and analog master level.

I don't run hyper-efficient horn speakers: mine are 88 and 90 db/W/m. But I found AJA ADA-4 DACs with 95 dB SNR too noisy and a Lucid ADA 8824 at 105 db fine. I could probably live with the ADA-4s with some gain structure tweaking, but would rather not. I think a 100 dB SNR figure is about as poor as I could go for theatre duty.

Over the years I've come to the conclusion that most power amps just have too much gain, and if they don't have any kind of input sensitivity adjustments (as many don't, mine included), then some sort of external input attenuation is just a fact of life if I don't want to spend thousands of dollars on DACs (which I dont, heh). If done properly, this attenuation needn't have any adverse effect on sound quality.

Thanks. Not knowing the model of AVR I still dont know what your reference is. I think you mentioned it, so I'll look back through the thread.

It's not about amp gain as much as system gain structure. One of the nice things about pro amps (well, that and SpeakOn connectors) is that they have input attenuators so you can run your interconnects hot and tone the signal down. This helps against noise from the previous stage and picked up on the interconnect (which should be minimal with a balanced line).

Hello,
see here, if you like:
Measurements on the nanoAVR HDA
The DAC _is_ noisy, at least in the configuration, used by the actual firmware.
And there is no hardware mute or similar to avoid crackling noise in an event of power down or off.
Additionally, the nanoAVR HDA relies on the etxernal grounding by the HDMI-cabling, which is neither reliable nor sufficient. Disconnecting the HDMI produces much hum. Due to the Cinch-connectors the signal outputs aren't "ground-free", so any noise on the ground adds to the audio signal, independent of symmetric/balanced amplifier inputs.
The remote volume control steps are 0.5dB, not 1.5dB. The latter may happen, if the remote TX sends three commands instead of one. One can configure that at a Logitech Harmony (Companion), I did. But the nanoAVR HDA's DSP soft mutes from -100.5dB down.
Cheers, Timo

This is very interesting and useful! Thanks.

It looks like the minidsp folks, DSP mavens that they might be, lacked experience with analog circuitry when this was designed. The performance of the SHD suggests they acquired it somewhere along the way.

In all fairness, though, proper grounding over HDMI cabling, unbalanced connections, and the small space in the enclosure make it difficult to keep noise out of analog signals. The AJA ADA-4 AES/EBU to analog DACs similarly sport poor (to my standards) SNR performance.

I had been considering an HDA upgrade to a nanoAVR DL to replace a Lucid 8824 DAC but will likely not. Right now I am going through an HDMI to SDI converter and SDI AES audio deembedder, so I can choose the DAC of my choice. I suspect the jitter is higher than desirable and might benefit from sample rate conversion to clean it up even if using a better DAC. Then again, the nanoAVR sample-rate converts on input and it is not clear how good it's clock is.

There is a space for HDMI to high resolution analog audio that miniDSP could fill (I really don't like using a converter to SDI that strips HDCP and limits me to 48 kHz) over balanced connectors, with volume control. Dolby, DTS, DSD, and Atmos codecs could be separately licensed plugins (as each has licensing costs) in the same way Dirac Live is. A software-configurable preamp.