Another project, all digital DDX amplifier

[hifimediy]

Originally Posted by AlexScan

I know that, but if I have 3 or 4 I²S signal pre-filtered (for example with this multichannel I2S board), how I can connect the different Tripath board in PWM mode ?

hi, I think that will be another product. We can build some board with I2S inputs then you can use it. but I prefer make the decoder and DDX together, which means we will have a S/PDIF or USB input and output multi-channels. Because I2S signal is sensitive that not recommended to travel long.

[hifimediy]

Basic functions for DDX320 board:
1. S/PDIF signal (Optical and Coaxial) input, 192kHz24bit acceptable and inner 96kHz24bit processing.
2. Channel switch by pressing button of rotary encoder, with LED indicate.
3. Long press button to enter standby (power down) mode, and again exit.
4. Rotary volume control, from -127dB to 20dB, 1dB/step. with 5x LED level display.
5. Setting data auto saving when power down, and restore when power on again.
6. Output relays for DC protection. And relay to turn on/ instant off.
7. On board 3rd channel cross over frequency setting(by 4x DIP switches). 80~360Hz with 20Hz/step. And pass through option.

anything I missed?

[SoldierAnt76]

Originally Posted by hifimediy

2. Channel switch by pressing button of rotary encoder, with LED indicate.
3. Long press button to enter standby (power down) mode, and again exit.
4. Rotary volume control, from -127dB to 20dB, 1dB/step. with 5x LED level display.
5. Setting data auto saving when power down, and restore when power on again.

anything I missed?

Is the "rotary encoder" you mention in #2 the same as the "rotary volume control" in #4? If you're using just one control for both power and channel selection, people might get confused - e.g., accidentally switching channels when they want to power down, or turn up the volume.

About #5 and #3 - will the settings be saved if there's a cold shutdown (i.e., power is completely disconnected), or only when the unit is in standby (i.e., the unit still consumes a trickle of power, even though it appears to be off)?

[AlexScan]

It's possible to add a second "sub out" for make a 2.2 DDX ?

[hifimediy]

Originally Posted by SoldierAnt76

Is the "rotary encoder" you mention in #2 the same as the "rotary volume control" in #4? If you're using just one control for both power and channel selection, people might get confused - e.g., accidentally switching channels when they want to power down, or turn up the volume.

About #5 and #3 - will the settings be saved if there's a cold shutdown (i.e., power is completely disconnected), or only when the unit is in standby (i.e., the unit still consumes a trickle of power, even though it appears to be off)?

Hi, yes we use one rotary to control. And there is no trouble because when control volume, we turn it, while channel switch we press it. If long press(about 2sec), it will be be a power down/on function. That is what we do on VC23 board.
And sure, it will remember the settings when cold off.

Originally Posted by AlexScan

It's possible to add a second "sub out" for make a 2.2 DDX ?

no now, it's just 2.1.

[SoldierAnt76]

Originally Posted by hifimediy

Hi, yes we use one rotary to control. And there is no trouble because when control volume, we turn it, while channel switch we press it. If long press(about 2sec), it will be be a power down/on function. That is what we do on VC23 board.
And sure, it will remember the settings when cold off.

My guess is that most people won't be switching channels often, and quite a few (myself included) will use a separate power switch wired to the SMPS for on/off instead of the standby function. But as long as the knob can't be pressed accidentally, it's probably okay.

How soon will units be available for sale?

[AlexScan]

Originally Posted by hifimediy

no now, it's just 2.1.

Ok but it is not possible to connect the 0.1 channel to two amplificator in PWM mode ?

[hifimediy]

Originally Posted by SoldierAnt76

My guess is that most people won't be switching channels often, and quite a few (myself included) will use a separate power switch wired to the SMPS for on/off instead of the standby function. But as long as the knob can't be pressed accidentally, it's probably okay.

How soon will units be available for sale?

I'm preparing the first batch, and soon you will find it on hifimediy.com.

[hifimediy]

Originally Posted by AlexScan

Ok but it is not possible to connect the 0.1 channel to two amplificator in PWM mode ?

Yes we can do that. The 0.1 channel we use an sta508 (mono mode) to drive now, and can drive 4ohm, or 2X 8ohm in parallel.

[AlexScan]

Originally Posted by hifimediy

Yes we can do that. The 0.1 channel we use an sta508 (mono mode) to drive now, and can drive 4ohm, or 2X 8ohm in parallel.

Ok the power chip was include inside the board !!!

This is not good for me I have two 4Ω/10" speaker for the bass in my system