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AK4490 USB Dac with dsd support.

Some comments.

Graviton power amplifier:

It will work with up to +/-50V. So output power depends on class A or class AB mode selected. Class A means less power as the dissipation is higher.

Output power is depending on the above configuration. I it uses 2 pairs of output transistor per channel to give good current drive.

And of course it has a build in SSR output protection circuit...
Thanks for your reply. I am in bed with pain so my brain is not functioning optimal: Is Graviton about as powerful as the TSSA V2? I choose the V2 boards back then due to them being more powerful than the TSSA 1.7 / 1.8. Thanks for your patience with me. All the best, Per
 
Yes it is.

In comparison to the TSSA V2 which have 4 mosfet of 125W/Package the Graviton has 4 BJT of 200W/Package.

So the heattransfer capacity of the Graviton is better. But as said, it depends on the heatsinks and supply voltage and VA/W rating of the powersupply.

BR

Sonny
Thanks for your answer. Very exciting :) Happy new year to you and all the folks in here. BR Per
 
Hi All.

There has been some who had told me that they did not have finance to buy before January. So i have decided to make extra coupon codes for the products on www.mirand-audio.dk

For those who have been late on sales we have the following coupons.

20%_discount_week1_2017 - 20% until end of week 1 in 2017

15%_discount_week2_2017 - 15% until end of week 2 in 2017

10%_discount_week3_2017 - 10% until end of week 3 in 2017

5%_discount_week4_2017 - 5% until end of week 4 in 2017


Now they cannot be used together. They are all active now, so remember to choose the right coupon to get max discount.
 
Can the spdif Dac be used without the fronpanel?
I mean can I fex update the firmware without it?



The new dac will have the feature to control a simple front panel consisting of only LED's and Buttons. If a bit more advanced frontend is needed and you don't want to have a display then it is also possible


Sent from my iPhone using Tapatalk
 
Hello Ryssen, Grunnet and Olebul. And all the rest.

The new DAC board is updated a lot.

USB side is isolated. Choices are:

1) USB powered USB
2) on board DC/DC converter on a picky bag board
3) external +5V power for the USB.

And also:

1) +5.5V power consumption is raised a little. ~50mA. -> more hardware on the board
2) Clocks are better.
3) reclocking.
4) SRC for SPDIF, Optical and I2S port
5) Backwards compatible
6) Support for a wide range of frontpanels-> new frontpanels on the tap
7) RPI adapter for feeding the I2S from the RPI to the DAC.

BR

Sonny
 
During xmas I had been following, quite amused, the debate about the qualities of Sonny-s discrete output in the Mirand dac.

I had been traveling, and had to get access again to Factory2nd's Mirand dac, but wishing to have a better look at it..

Here it is the performance of Sonny's Mirand Dac+discrete shield into my EMU1616m sound card.
Usually I'm testing at a lower than maximum output level, more relevant to real listening situation. The sweet spot in my EMU card is usually at -10db wit respect to Full Scale.
The dac is having an above average output level, so it's -10dB FS is fitting well to the ADC 0 dB full scale in the EMU card. The Single Ended output is used, and he EMU card is set to Consumer level input, -10dB setting.
Also, I'm using 44.1 kHz sampling, so as to be able to reveal this low levels of distortion..
The performance get's more 'real world' like at higher frequencies. I got 0,0002% THD at 5kHz, and 0.0003% THD at 10kHz.

Also, work is in progress for eliminating the residual hum still visible.
Not an easy task because of the large ground loop created in the measurement. (DAC is not isolated, and the measurement is not balanced)

Concluson: I got quite much baffled when I first had seen this. It's kind of better than most opamp outputs..

Ciao, George
 

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During xmas I had been following, quite amused, the debate about the qualities of Sonny-s discrete output in the Mirand dac.

I had been traveling, and had to get access again to Factory2nd's Mirand dac, but wishing to have a better look at it..

Here it is the performance of Sonny's Mirand Dac+discrete shield into my EMU1616m sound card.
Usually I'm testing at a lower than maximum output level, more relevant to real listening situation. The sweet spot in my EMU card is usually at -10db wit respect to Full Scale.
The dac is having an above average output level, so it's -10dB FS is fitting well to the ADC 0 dB full scale in the EMU card. The Single Ended output is used, and he EMU card is set to Consumer level input, -10dB setting.
Also, I'm using 44.1 kHz sampling, so as to be able to reveal this low levels of distortion..
The performance get's more 'real world' like at higher frequencies. I got 0,0002% THD at 5kHz, and 0.0003% THD at 10kHz.

Also, work is in progress for eliminating the residual hum still visible.
Not an easy task because of the large ground loop created in the measurement. (DAC is not isolated, and the measurement is not balanced)

Concluson: I got quite much baffled when I first had seen this. It's kind of better than most opamp outputs..

Ciao, George

Thanks for the measurements you have done, It is better to have a non affiliate to do such measurements.

Thanks again.

BR

Sonny