Need Your Advice on Developing a 5.1 Channel DAC

[Times]

I have to agree with the members saying a 5.1 might not be the right product to focus on. I'd like to see you guys going more into that direction:

Sorry Fosi, HDMI input and USB, 2.1 Amp with 10 band peq is more attractive to me.

A 2.1 Amp / Pre-Amp (maybe both, the same platform with the amping section being internal or external) with the following features:

Inputs:
- 2x unbalanced RCA
- 1x balanced XLR
- digital Coaxial and Toslink
- Bluetooth
- Ethernet

Outputs:
- Headphones (front)
- 1x unbalanced Pre-Out
- 1x balanced Pre-Out
- 1x Sub Out
(- Speaker out, if it's an amp)

Other:
- Volume and Input knobs on the front
- Standby button on the front, power switch on the back
- Remote (optional, optional if there's app control)
- Room Correction (!) maybe optional through additional license (Dirac, Audyssey,…)
- Firmware upgrades
- Color options black and silver

Would love to see something like that. The new miniDSP Flex balanced is almost a perfect fit for me, but I think some competition would be great.

thanks,
Times

 

[Guddu]

if this product turns out a decent dac/decoder, and I hope it does, then it may not be for everyone but will surely be a great low cost alternative for smaller deployments.

If there aren’t any additional licensing costs implication for DD/DTS 5.1 decoding then a decent low noise/distortion decoder for low price isn’t a bad product.

 

[Fosi Audio]

Hi all,
Based on your advice, we have redefined the product.
We look forward to your further suggestions.

The picture below shows the concept design of this product. Besides the I/O, it will also have/support：
1. remote control
2. capable of decoding Dolby True HD and DTS HD
3. 100W*3(CEN、FR、FL channel）+50W*2（RL、RR channel）
4. display screen
5. two HDMI eARC interfaces

 

[Graham849]

@Fosi Audio This is getting very interesting. Thank you for moving this concept along.

I think that there is one or two controls still to be added to the front panel.

Firstly a choice of using stereo or 5.1 output and also decoding choice - DTS, Dolby Digital, and normal stereo.
Or maybe these choices are provided by the remote control?

Also a USB input , thank you!

Looking forward to the next iteration!

 

[voodooless]

That’s a totally different product . I haven’t seen anyone advocating for putting amps in the thing.

 

[TonyJZX]

yeah why does it have amps in it now?

 

[Guddu]

Hi all,
Based on your advice, we have redefined the product.
We look forward to your further suggestions.

The picture below shows the concept design of this product. Besides the I/O, it will also have/support：
1. remote control
2. capable of decoding Dolby True HD and DTS HD
3. 100W*3(CEN、FR、FL channel）+50W*2（RL、RR channel）
4. display screen
5. two HDMI eARC interfaces
View attachment 320112

The 5.1 output section in pic doesn’t look right, previous pic had correct 5.1 pre-outs layout.
1) It’s unbalanced out, so each RCA is 1 channel. Example, FR should be 1 RCA not a pair.
2) Subwoofer or .1 channel out is missing.
3) What is the separate 3.5 “PREPUT” in the pic? Headphone out?
4) You have shown “watts” in the description, it’s not applicable on a DAC or pre-amplifier.
5) 2 HDMI eARC input is good addition, but eARC can also do 5.1 DD+ ?
6) Will each channel have volume control through remote?
7) No stereo vs 5.1 selection switch, will remote has option to switch and select 5.1 or stereo?

Thanks for the concept

 

[Vini darko]

Competition is fierce in the AV market. Good luck.

 

[jhaider]

1. remote control
2. capable of decoding Dolby AC-3 and DTS
3. display screen

View attachment 317411

A few things to make it useful:
1) much better UI - master volume on the front, small pots or digital interface for individual channel volume. Web-based UI to control nos. 2-5 discussed below.
2) level adjustment for each channel, not just pairs
3) useful bass management (per channel selectable freq and slope)
4) useful PEQ for each channel - let’s say 8-12 bands per channel with selectable shelf or bell filter shape.
5) loudness compensation (see, e.g. Monoprice HTP-1, RME ADI-2)
6) 2V preout minimum, a little more is better.

An upmixer would be nice too - is Dolby Pro Logic II a reasonable license fee? It’s old, but good.

 

[Jeromeof]

Hi all,
Based on your advice, we have redefined the product.
We look forward to your further suggestions.

The picture below shows the concept design of this product. Besides the I/O, it will also have/support：
1. remote control
2. capable of decoding Dolby True HD and DTS HD
3. 100W*3(CEN、FR、FL channel）+50W*2（RL、RR channel）
4. display screen
5. two HDMI eARC interfaces
View attachment 320112

Interesting - are those Speaker binding posts as they look like RCA outputs but it wouldn't make sense to have 2 for FR and 2 for FL etc?

Where is the subwoofer output? As preout might work but only if you have some crossover filters and obviously the volume controlled on the preout?

Why 2 HDMI EARC inputs? Not that many people have 2 TV's in the same room but maybe if one was input and the other HDMI was the output - i.e. chain the device between a Fire stick or an Apple TV and someone's TV?

 

[hex168]

A few things to make it useful:
1) much better UI - master volume on the front, small pots or digital interface for individual channel volume. Web-based UI to control nos. 2-5 discussed below.
2) level adjustment for each channel, not just pairs
3) useful bass management (per channel selectable freq and slope)
4) useful PEQ for each channel - let’s say 8-12 bands per channel with selectable shelf or bell filter shape.
5) loudness compensation (see, e.g. Monoprice HTP-1, RME ADI-2)
6) 2V preout minimum, a little more is better.

An upmixer would be nice too - is Dolby Pro Logic II a reasonable license fee? It’s old, but good.

"An upmixer would be nice too - is Dolby Pro Logic II a reasonable license fee? It’s old, but good." Great idea.

 

[GXAlan]

Hi all,
Based on your advice, we have redefined the product.
We look forward to your further suggestions.

The picture below shows the concept design of this product. Besides the I/O, it will also have/support：
1. remote control
2. capable of decoding Dolby True HD and DTS HD
3. 100W*3(CEN、FR、FL channel）+50W*2（RL、RR channel）
4. display screen
5. two HDMI eARC interfaces

What is your target price point for this? Is it cheaper if you drop the amplifier and have 5 balanced XLR outputs?

This is great esp. if you also have HDMI CEC for volume control.

A web based interface or OSD would be great.

Agree with Dolby Pro Logic II.

 

[tinnitus]

Hello @Fosi Audio ,
what is missing is a flexible modular multichannel DAC. I use digital crossovers for my stereo system. In my two way system that is 4 channels.
I have a Topping DM7 as DAC but use only 4 channels of it. I would like to have a DAC that can be upgraded with plug-in units. DAC units with 2 or 4 channels, which can be installed several times.

Basic DAC with one olug.in with 2 channels "standard stereo".
Two plug-in units each 2 channels for a two-way system.
Or one insert with 4 channels and an insert with 2 channels, altogether 6 channels for a three-way system or a 5.1 Sourround system.
Four times 2 or two times 4 for 7.1 for a four-way system........

That's what I mean by flexibility. For analog balanced output per channel I would suggest 3.5 trs, otherwise it will probably be a little tight on the back ;-)

 

[dannut]

@Fosi Audio - thank you for having the courage to bring something useful to the market.

MiniDSP has a FlexHT in the pipeline, now you have something brewing - a simple solution (eARC audio processor/DAC/AMP?) for simple multichannel needs.
I would gladly make a shortlist of features that are minimally needed for proper TV-based system setup:

• eARC input wiht bitstream (E-AC-3/AC-3) decoding, and DolbyMAT (for AppleTV) support
• some 'simple' DSP (implemented in this order):
  • upmixing for 2ch sources (please license Dolby Prologic2 - this suite has a useful 'Music' mode in it. Should be a bundle with DolbyDigital/AC3 decoding)
  • bass management for all audio channels
  • delay/level/EQ for all speaker-channels (would be nice to have 3-5 band parametric EQ per channel)
    • bonus point for having 2-3 independent SUB-Out channels with separate processing and/or
    • 'Advanced' user mode for uploading Biquads/FIR coefficients.
• If you want to implement amplification stages, great! 7ch TPA3255 please
• Balanced TRS for line-level out, Speakon NL2 for speaker level
• A remote. Volume and 'bass'/'treble' controls.
• Make it modular?:
  • TIER 1 - 5.1
  • TIER 2 - 7.1 (3 separate sub-out)
  • TIER 3 - 7.3.4 support with Dolby Atmos suite licence

 

[Fosi Audio]

yeah why does it have amps in it now?

Hi there, this is a 5.1 channel amp+dac. We can connect it to the TV via HDMI eARC, and then connect passive speakers through an amplifier to create a 5.1 home theater system, decoding and playing Dolby/DTS movie resources.

 

[phoenixdogfan]

As long as you are starting from scratch, why not a 10 channel USB Dac? While Atmos over Windows and Mac Pc's is not yet a thing, it's entirely possible that it could materialize someday soon. If it does, a 10 channel Dac would allow an LPCM decoded 5.1.4. Atmos signal to be passed directly to your DAC and from there to the amps which would obviate the necessity for a bulky, expensive AV Atmos receiver. Just imagine: A Mele Quieter 3 rendering a Netflix Atmos audio feed via JRiver to your Dac and from there to five Aiyima A7s and a powered sub! Cheap, compact home theater in a small room!

In the meanwhile, 10 channels would allow for a 7.3 surround set up with three distinct subs, or even a software based 5 way stereo setup. So 10 channels at a minimum please!

Edit: Or a ten channel Fosi Audio Amp. Didn't realize who the OP was!

 

[GXAlan]

Hi there, this is a 5.1 channel amp+dac. We can connect it to the TV via HDMI eARC, and then connect passive speakers through an amplifier to create a 5.1 home theater system, decoding and playing Dolby/DTS movie resources.

What is your target price? There may be value in having this as a 5.1 channel processor for use with active speakers.

If this is $100, it's one good option. If it's $1000, the 2.1 Sonos Amp might be a better option when paired wireless rears.

 

[MCH]

Hi there, this is a 5.1 channel amp+dac. We can connect it to the TV via HDMI eARC, and then connect passive speakers through an amplifier to create a 5.1 home theater system, decoding and playing Dolby/DTS movie resources.

So this is now a sort of small AVR, but with no DSP capabilities, stereo line level out only...Does the USB input support multichannel?
Like everything, there will be people needing something like this, but I don't think the ASR audience will jump on it.

Btw, you are missing one channel. 5.1 means 6 channels. You are missing the subwoofer unless it is the line level output.

 

[TikBLang]

This device should have at least, in my own opinion, a 7-channel device plus the sub-output (7.1 minimum.). The setup is 5.1 plus the two speakers pointing upward (toward the ceiling) and can be placed on top of the front left and right floor speakers (or on the sides as aux left and aux right respectively) . 5.1 is, I think more than two decades old.

 

[voodooless]

The setup is 5.1 plus the two speakers pointing upward (toward the ceiling

What’s the point? There is no decoding for anything with height channels..