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Curious about the (quite good!) analog input performance: does anybody know what ADC & DAC chips are used? I believe the Sharc ADSP-21489 DSP is pure digital, correct?
ADC chip: TI PCM4202 https://www.ti.com/lit/ds/symlink/pcm4202.pdf
DAC chip(s): TI PCM1795 https://www.ti.com/lit/ds/symlink/pcm1795.pdf
Or velcro.That's what BluTak is for, no?
I just use a cheap laptop--some HP plastic cheapie that I bought on sale at Best Buy. I was about to abandon it, because the fan started getting noisy. But I found a replacement fan on Amazon for $8 and it only took ten minutes to replace it, and blow out all the cat hair that was making it noisy in the first place. It's silent again. I think I'll buy several of those fans for the future--by the time I use them up, I'll have to replace the thing anyway. It connects to my home network via WiFi, and the Music Bee player software I use can access the library on my home server. I suppose it could also access the online streaming service.
The good news is that I can also run Vinyl Studio on it for making needledrops, and it works fine running REW, Audacity, and Presonus DAW software, at least for the simple things I do.
With a device like this, I can still use my Benchmark ADC (which has superb front-panel indications and controls) for making needledrops, and use this as the input for other devices.
Rick "cheaper than many streamers, even with the price of the DAC" Denney
I have no doubt it does for some.So Darko was right? Does it improve the tone though?
Good post, thanks. I wonder if this is due to comparing 4V balanced vs 2V unbalanced input levels?Regarding using unbalanced input adapters on the balanced Flex, I noticed miniDSP recommends specifically not doing this due to a 15 dB SINAD drop, so be aware that while it'll work, they do call out a performance issue when doing so:
WARNING: This connectivity work (TRS to RCA) workaround is ONLY to be used for outputs. We've noticed a performance drop on outputs (15dB SINAD drop) for that reason will not recommend customers to use an unbalanced to balanced cable on the "input" side of the Flex. If you want to have unbalanced in/out for both inputs and outputs, it's strongly recommended that you just use the miniDSP Flex unbalanced version. The miniDSP Flex was engineered with best performance in mind and it's therefore our intention to stay consistent on making sure best audio quality is kept for this platform!
It tends to be confusing...in some (most?) cases it would be better to buy the unbalanced version if you are using unbalanced inputs, then connect the unbalanced output to the balanced input on the amp/monitors via properly terminated cables. This is frequently misunderstood (most often by me)...there is no real downside feeding the unbalanced output to the balanced amp input.
Doing the conversion on the input side can be more problematic (though of course, not always).
MiniDSP recommends purchasing the unbalanced model for mixed use cases like this.
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If I made use of this, I would need balanced outputs to my main speaker amp (Pufifi) and unbalanced to my subs (SVS), so I would probably use something like a Benchmark Balanced to RCA with a floating ground for the sub channels. I would need a balanced TRS to Balanced XLR cable to connect the XLR end of the Benchmark cable.Good post, thanks. I wonder if this is due to comparing 4V balanced vs 2V unbalanced input levels?
My own use case for Flex device(s) would be for my music/HT setup (colocated but separate 2-ch and AVR systems, up to the shared 2.x preouts to shared amps/speakers/subs). If I use a 4V clean unbalanced out AVR (i.e. one of many Denon's, etc.) that already are in sub-100dB SINAD range, the Flex unbalanced SINAD drop even if either 2V or 4V level should be of no audible consequence?
Thank you for explaining this. Still learning a lot here. So, unbalanced is really the way to go if one wants to plug their old analog gear in. The SNR will get chopped down on the TRS version when using single ended (RCA) inputs.My thoughts on this are similar to the response you got from Feynman.
Full scale input and output on the RCA version is 2.0 Vrms
Full scale input and output on the Balanced version is 4.0 Vrms.
Consider the output levels of your legacy RCA equipment and to what extent of full scale they are able to drive the analog inputs of the Flex.
For example, the Zone 2 output of my Yamaha AVR drives at 200 mV. Hooking them up directly, I'm going to be throwing away a lot of SNR / ADC bits and won't be getting a lot of volume out of my amp. I haven't tried it yet, but suspect I will need to find a gain stage to put in between. It would be better to attenuate balanced outputs into RCA inputs in my opinion.
you will lose roughly 18dB of S/N. but since i already run my master volume at -20 dB with no hiss whatsoever i don't think it's an issue at all.For example, the Zone 2 output of my Yamaha AVR drives at 200 mV.
Yes. MiniDSP has free PC software that connects to the Flex via USB where you can set LP and HP crossovers for all 4 channels as well as time delay, etc. It's great for bass management with up to two subs. Dirac works like a next step, additional software functionality that generates a target curve (that you can modify) based on measurements of the room.
OK does this mean that I can shove the FIR tap into the unit?
I have always thought of Dirac more like speaker correction and the PEQ stuff as room correction.
Thanks, but I am not seeing any unbalanced signal to Flex balanced input connection (and the associated Flex SINAD drop question) in this scenario at all.If I made use of this, I would need balanced outputs to my main speaker amp (Pufifi) and unbalanced to my subs (SVS), so I would probably use something like a Benchmark Balanced to RCA with a floating ground for the sub channels. I would need a balanced TRS to Balanced XLR cable to connect the XLR end of the Benchmark cable.
You have a choice of either having Dirac Live functionality or sticking to the cheaper Flex without Dirac Live and having manually adjustable FIR filter capability. You can't have both.
I'd suggest more the opposite personally. I've used the PEQ filters on other miniDSPs to apply speaker correction based on quasi-anechoic measurements, whilst I'd view Dirac Live an principally software to adjust the in-room response. Yes it does its impulse correction thing as well, although I find it impossible to judge its value since you can't choose to turn this aspect on/off in isolation.
Personally I like the results of using Dirac Live just in the low-bass region rather than over the full frequency range. Others like the latter but I would encourage anyone to experiment with both to see what they enjoy most.
Ok, so if I want to use something like rePhase or Eclipse’s-FIR Creator or FIR-Designer (or something else), and I can show the FIR taps in with only the cheaper option?
And with Dirac I cannot get the taps/weights out? And can also get the weights pushed in?
or is it… why would I want Dirac if I only want to push the taps/weights in?
I would like to use it for a 2-way XO, and also the sub’s XO.