Khadas tone board Generic vs tone board VIM

[Blackhawk]

Hello Everyone, I have been reading about the Khadas tone board. If I understand it correctly, the VIM edition can do everything the generic edition can do, plus it supports SPDIF OUT and connectivity to VIM boards.
Is this correct?

The generic edition can be converted to a VIM edition, simply by soldering the 20 & 40 pin headers to the board. Doing so will enable it to function exactly like a VIM edition. Is this correct?

How is the SPDIF OUT enabled on the VIM edition?

Where do I find the casing for TB VIM?

Thank you in advance for your input.

[wanthalf]

Yes. The only difference is that the VIM version has the headers already soldered on.

The SPDIF-out works if (and only if!) the ToneBoard is connected to the VIM through its header, because it does not actually depend on the ToneBoard version, but on the presence of the VIM. It is not the ToneBoard, but the VIM that provides the SPDIF output signal technically! The ToneBoard only provides the physical connector and routes the SPDIF output signal from the VIM to the connector. So, you actually do not need the ToneBoard for this purpose at all, you can just use the SPDIF output of the VIM directly as well using a very simple adapter with a connector.

That’s at least how I understand it. I hope I am correct.

[RDFTKV]

Hello, You are correct.
Makes sense, as TB’s job is digital to analog conversion.

[Blackhawk]

Great. Thank you guys for taking your time to reply.

How about the casing for TB VIM. I believe it uses a different casing from the generic. Audiophonics only carries the generic casing.

[Blackhawk]

Okay, I have read about the casing for the TB VIMS. I understand I have to fabricate it. Maybe I will make a box using plastic and chlorofoam or just place it in a cardboard box and hide it behind the furniture.

[RDFTKV]

The VIMs’ DIY case(clear with metal plate used here(SKU: KCS-T-001)) can be reconfigured to house the TB, as long as you are not hung up on the whole sides thing.

The case could also be made into a vertical enclosure.

If sides and front are desired, some could be fashioned from something like Band-It veneer edging, balsa or other material.

While this would cost a few dollars more than the cardboard box, it’s only a few.

(Tone board VIM version used)

[Blackhawk]

Simple and fantastic design.

It looks like the VIMS transparent case placed upside-down without the side cover.
And I need to buy the 4 corner metal connectors separately.

Also, is the TB screwed to the top metal plate?

Do I need to modify anything?

Many thanks.

[RDFTKV]

Yes, clear case, turned upside down. I did that because I like the metal plate and logo look. Also, the TB VIM version has the GPIO header mounted, I had to invert the case top(used as bottom) to allow the header clearance, and that would not be as pretty if if were on the top.

As to the nuts, bolts and threaded brass standoffs, all fasteners came from Khadas products(VIM1,VIM2, DIY case and Tone board), not sure what came with what at this point. Both the DIY case and TB come with some fasteners, check their respective product pages for details.

Fasteners are all M2-.4, aka 2mm. You may have to purchase some fasteners from the Bay or Amazoon to complete the fastener list. Suggested search term: m2 brass fasteners(or standoffs). Kits are available with a multitude of M2 fasteners for around $10 on the aforementioned sites and elsewhere.

Hole spacing on the VIMs and the TB are the same, so yes, mounted the TB to the case bottom(used as top), metal plate is attached to case, metal plate and TB don’t share fasteners. Added studs for board and attached metal plate prior to mounting the TB. I had to double up the brass corner standoffs because I had none long enough. Since you might be buying those, you can pick a suitable length. Standoffs could be substituted with bolts and nuts if you preferred, but to avoid electrical shorts, make sure the fastener does not extend past the pads on the PCB’s bolt holes.

Nothing has to be cut or physically modded, however, if you want to get all three control nuts on the output connectors, some material removal may be required. The nuts are cosmetic in this instance, so I just left one off(right channel). Could also make the studs that hold the board longer, so the Control nuts would clear the case section.

It is certainly easier than it sounds here.

If you have questions about the case after you get your TB, I will attempt to answer them.
Have fun.
Some pics to show some assembly detail…

[Blackhawk]

Thanks a million for the illustration.

I will check it out when I have got it.

[wizardofoz]

I used this…pretty happyy with the results for not many $

Khadas tone board case by -Frost-

[Blackhawk]

Do you mind sharing some close up photos?

[wizardofoz]

[Robert]

Very neat should be able to find a hobby box about that size:
Looks Great what you have done

[Lumpy]

Spent quite a bit to work out if the TB can be fed from USB and output to SPDIF, so that kind of ruins my plan , was supposed to arrive today, guess it’s going back.
The specs sheet says in/out but doesn’t say you need the VIM and that it’s just passthrough not actually using the DAC. My amp only has digital inputs, so guess will stick with the built in USB DAC.

[Vladimir.v.v]

Welcome!
in fact, you don’t have to have vim. Please tell us what will your connection diagram be?

[Lumpy]

Pi Zero for now, was looking at a VIM 3L, but maybe in a separate case to the TB, so I can use the TB with other SBCs.

Pi Zero W (Volumio) -> TB via USB -> NAD D7050 via SPDIF coax

The NAD has 24/96 on USB DAC and 24/192 on Digital inputs. Guess the question would be, is feeding the source via SPDIF sound better than the USB, different DACs used inside the amp?

[Vladimir.v.v]

I won’t guess, I know that people like the sound of TB

[Lumpy]

So in that “diagram” would the TB act as an USB DAC and send a digital out over the Coax/SPDIF?
Or would this not work and defeat the purpose if not using the analog RCAs out?

[Vladimir.v.v]

@Lumpy

USB DAC and send a digital out over the Coax/SPDIF

Yes,will transmit to RCA, this is DAC

[Electr1]

@Lumpy it will work, no problem,
The “NAD D7050” you are using is going to basically going transmit the audio signal from the Toneboard DAC, there should be no problems,

@Lumpy

is feeding the source via SPDIF sound better than the USB

That is questionable, The DAC basically can have a max sample rate of 384000Hz, If you can feed the data that fast, you can have that much better of a audio signal…

Going with a RPi zero, it seems like a good combination for listening to just music, streaming might struggle due to the processer bottleneck, we recommend using a bit more powerful system (if streaming is going to be done)

good luck with your project…