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.
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?
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?
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.
no now, it's just 2.1.
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?
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 ?
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
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
But we also have more powerful chips, when sta510 or 517B used, we can handle down to 2ohm speakers.
Any chance we can ask at checkout for 2 optical inputs to be soldered on or can this be easily done by the end user? I have 2 optical sources and no spdif coax sources
BTW hifimediy, i would love to see your version of a miniDSP hopefully running with a lower cost and preferably with digital input and outputs built in, hell i wouldnt care if it had no analog inputs, 6 bands of parametric per channel or a good 32 channel graphical paired with this amp would be a sweet little system. Really doesnt need a physical interface either, Id set and forget over a usb from comp.
Fully digital sound, including high bit rate EQ would make a very happy customer of me
Next project maybe? *nudge nudge*
Thanks for what is hopefully a nice amp here though!
BTW hifimediy, i would love to see your version of a miniDSP hopefully running with a lower cost and preferably with digital input and outputs built in, hell i wouldnt care if it had no analog inputs, 6 bands of parametric per channel or a good 32 channel graphical paired with this amp would be a sweet little system. Really doesnt need a physical interface either, Id set and forget over a usb from comp.
Fully digital sound, including high bit rate EQ would make a very happy customer of me
Next project maybe? *nudge nudge*
Thanks for what is hopefully a nice amp here though!
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Yes it would be nice. But I would happily settle for a nice simple three or four channel power stage that could additionally take i2s inputs direct from the miniDSP or DAC etc. In fact, although total costs would be higher, I would prefer this for the flexibility it would give. Bit of a shame that the DDX isn't being built like this really - it could sensibly be an i2s coupled pre and power stage .
With the minidsp and the minidigi plugin for it you will essentially have that system when combined with hifimediy's ddx amp. Minidsp will accept analog or 2 optical inputs and will output on another optical spdif to the ddx amp. All set. I just imagine hifimediy's won't cost $160-$170.
Obviousoy though you are still limited to a 2.1 system. Minidsp does output upto 4 channels via i2s we just need someone to build a bigger version of the miniAmp.
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Of course we will not Limit here, DDX320 will be our first step, and we will have more later, different boards for different use.
Of course we will not Limit here, DDX320 will be our first step, and we will have more later, different boards for different use.
I look forward to it !
Ok so 3 questions.
First the big one! Can't believe I forgot to ask this, what slope is the cross over filter for the .1 channel? I hope it's -18dB or better as a -6dB or some such would be near useless for my purposes.
2) will the amp chipset you will first ship with be able to handle a 5.6ohm load for the main speakers and a 6ohm sub load? Or will I have to wait till you start using different amp chips?
3) is there a seperate volume control for the .1 channel (or main channels) or will I have to control all my bass output via EQ? This could be limiting for those who do not plan to buy a miniDSP or who have a 16band GEQ on their comp.
Thanks,
Mitch
First the big one! Can't believe I forgot to ask this, what slope is the cross over filter for the .1 channel? I hope it's -18dB or better as a -6dB or some such would be near useless for my purposes.
2) will the amp chipset you will first ship with be able to handle a 5.6ohm load for the main speakers and a 6ohm sub load? Or will I have to wait till you start using different amp chips?
3) is there a seperate volume control for the .1 channel (or main channels) or will I have to control all my bass output via EQ? This could be limiting for those who do not plan to buy a miniDSP or who have a 16band GEQ on their comp.
Thanks,
Mitch
I'm preparing the first batch, and soon you will find it on hifimediy.com.
I keep checking
any updates for us?Hi Mitch.
The filter is about -12dB.
And the amp can handle 6ohm stereo and 4ohm sub. So, it's ok to use for 5.6ohm when you keep the supply voltage a little lower.
We can add some code to control the bass volume separately.
Thanks for your ideas.
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