SDTrans 384?

[adolfo.a.aguiar]

Here's my SDTrans384 + Soekris combo.



Both are as bought, without upgrades. I'm using a 5VDC reg for the SDTrans instead of the wallwart.
The SDTrans improves a lot with burn-in and I'm delighted with the SQ. It's very detailed, tonally accurate and dynamic. My heavily optimized PC sounds as detailed but clinical in comparison.
I will enjoy my collection for a few more days before start modding.

[nige2000]

at last pictures:)
What usb to i2s did you have on the soekris?
Seems less noisy ?

[Sligolad]

Had a feeling 2016 was going to be a real interesting year for digital audio....great work guys!
I have been following all these threads with great interest.

[adolfo.a.aguiar]

at last pictures:)
What usb to i2s did you have on the soekris?
Seems less noisy ?

DIYINHK isolated.
Much less noisy. I keep on hearing things that surprise as not heard before in well known recordings. And this without mods.

[gstew]

From the picture on page 1, I think IC1 is the I2S to LVDS converter, since it is right next to the HDMI connector (unless I am looking at it incorrectly)

So, it seems you should be able to remove IC1 (or 4 the LVDS converter), and IC6 at least. This assumes you only use I2S directly from the SDTrans.

I might also try bypassing IC7, and see if it sounds better without IC7. If so, you could remove that part also.

Randy

Randy, you are correct, it is the IC1 that is the LVDS converter... see picture. Sorry!

If it were me, I'd first try un-powering the S/PDIF & I2S output chips by pulling CN7 and removing the I2S series Rs from the FPGA... looks like R22-R24 for the I2S lines, not sure on the clocks, probably R40 & R47 coming directly from the clocks. Then get I2S from the input pads of those resistors. That would do the same with the least amount of component removal... though it would still leave the feeds to the S/PDIF and LVDS chips active. Rather than remove them, I'd suspect if those of us interested approached the designer for a custom ROM that would not output to the S/PDIF & LVDS chips, he'd do it (for a price, but that should provide additional benefits).

Based on what both Rick and Adolfo wrote, I suspect mine needs more run-in as my still-stock SDD being fed via an R-Pi is more tuneful than the also stock one being fed via my SDTrans. As I've also got more music transferred to SD cards now, it'll go back into a system!

[randytsuch]

A slight mishap delayed shipping, but my sdtrans shipped today from Switzerland, figure I'll have it next week.

I'm thinking about a future project to use an Arduino as a remote control for this board.
Using the Remote I/O interface connector, it seems like it should be fairly straightforward to do this.
I've made some project with an Arduino a few years ago, so I think I can figure this out.

Randy

[gstew]

A slight mishap delayed shipping, but my sdtrans shipped today from Switzerland, figure I'll have it next week.

I'm thinking about a future project to use an Arduino as a remote control for this board.
Using the Remote I/O interface connector, it seems like it should be fairly straightforward to do this.
I've made some project with an Arduino a few years ago, so I think I can figure this out.

Randy

Glad yours is on the way. VERY interested in what you come up with on the Arduino remote, perhaps a single unit that will control the Soekris SDD (filter changing and normal/inverted) and the SDT (ESPECIALLY if it could enable fast-forward/reverse) would be very interesting.

I'm watching what everyone else does to these. I added Panasonic SMD PPS caps across all of the post-reg electrolytic and damped the metal shield over the reader and all of the electrolytics. All that plus some run-in time made it smoother.

The Panasonics were my low-cost alternative to the Sun-Ring copper foil PPS caps, which I am sure are better, but I had the Panasonics here and as such, the price was right.

Greg in Mississippi

[randytsuch]

Glad yours is on the way. VERY interested in what you come up with on the Arduino remote, perhaps a single unit that will control the Soekris SDD (filter changing and normal/inverted) and the SDT (ESPECIALLY if it could enable fast-forward/reverse) would be very interesting.

I'm watching what everyone else does to these. I added Panasonic SMD PPS caps across all of the post-reg electrolytic and damped the metal shield over the reader and all of the electrolytics. All that plus some run-in time made it smoother.

The Panasonics were my low-cost alternative to the Sun-Ring copper foil PPS caps, which I am sure are better, but I had the Panasonics here and as such, the price was right.

Greg in Mississippi

You'd probably get a bigger improvement by using lifepo4 batteries in place of the 3.3 and 2.5 v regs on the board.
There is one 1.2v reg that lifepo4 won't do directly. It's pretty easy to make a 1.2v reg though, I did it for the FPGA on the Soekris dac.

I forget about soekris control, but that should be pretty easy, just need to send rs 232 commands from the arduino to the dac.

And play, ff and reverse should be pretty easy too, it is just grounding the pins at the remote connector.

I would also like to be able to read what's on the screen, not sure if that's possible or not.

The harder part is controlling the arduino, if you don't have a PC connected to it. You can make an arduino read a IR remote, but I haven't tried that yet.

Randy

[gstew]

Randy,

Thanks for all the tips. I'm hopeful you do get to the point of being able to remote-control the SDTrans AND the SDD through an Arduino... I think dimdim already has posted some stuff on his SDD-Arduino interface. Me, I'd just like to be able to change the filters and invert the output of the SDD without having to whip-out a computer!

Also, note that FF/Reverse is not available AFAIK on the switches on the SDTrans. I'm wishfully hoping it is available if you do a direct interface, but I'm not holding my breath!

On batteries, yah, I'll get there. My intention is the try and get a mains-powered setup working and sounding as good as I can, THEN going to battery power in a limited way on a couple pieces of gear to see how well I did. I'd like to stay mains-powered, so if I can get things really close, I'd keep them there. OTOH, I fully expect to be converting it all to battery power after I try them!

Later!

Greg in Mississippi

[randytsuch]

Randy,

Thanks for all the tips. I'm hopeful you do get to the point of being able to remote-control the SDTrans AND the SDD through an Arduino... I think dimdim already has posted some stuff on his SDD-Arduino interface. Me, I'd just like to be able to change the filters and invert the output of the SDD without having to whip-out a computer!

Also, note that FF/Reverse is not available AFAIK on the switches on the SDTrans. I'm wishfully hoping it is available if you do a direct interface, but I'm not holding my breath!

Greg in Mississippi

I have a dimdim adapter board for the Soekris which I may or may not use for this project. And I've looked at his code, I think I understand what he is doing.

Maybe I misunderstood the buttons, I will be able to make it look like you're pushing any of the buttons on the sdtrans card, play/stop, forward, reverse and mode. I won't be able to add anything that is not already there.

Randy