• Disclaimer: This Vendor's Forum is a paid-for commercial area. Unlike the rest of diyAudio, the Vendor has complete control of what may or may not be posted in this forum. If you wish to discuss technical matters outside the bounds of what is permitted by the Vendor, please use the non-commercial areas of diyAudio to do so.

Introducing the bit "Teleporter"

Teleporter with MiniDSP MiniSHARC.

Hi,

I'm currently designing an active 3-way stereo loudspeaker pair with a MiniDSP MiniSHARC, Teleporters and Opus DACs.

Anyone have experienced with connecting the MiniSHARC I2S output lines to a Teleporter and passing them on to an another MiniSHARC? See the proposed connection scheme in the attached image. The MiniDSP devteam asked to verify that the Teleporter can work in I2S Slave mode with the MiniSHARC. Should it work like this?

Btw, I couldn't find any manuals or spec sheets of the Teleporter? Do we have any available?

Thanks in advance,
Timo
 

Attachments

  • digital.JPG
    digital.JPG
    71 KB · Views: 403
Great news!
I just borrowed a really good 50 foot shielded cat 6 cable and all of my dropout issues are history. Everything works perfectly. If you have experienced problems with momentary dropouts from lights or fans or ovens or chairs, a quality shielded cable may be all you need. I am jumping the ground to the connector on the transmitting side but leaving it open on the receiving end so the cable only grounds to the chassis. Of course I do have a single star ground between power and the chassis and 3rd wire earth power ground.
 
Hi, I read the thread and looked at the topics in TP support, has any manual been created for these modules?

The specific questions I have are, can this module do SE to Balanced/Diff conversion? or am I limited to whichever ins/outs I use? Also, there was mention of 10kohm on the SE outs, is that to ground or in series?

Thanks
 
Did a bit more digging. the SE ins/outs are tied down to ground with 10k ohm resistor, no series R between in/out and the chip.

No this device doesn't do any SE to Bal conversion, it does buffer, isolate using differential pairs, transmit. No common ground unless you want it via closing jumper J2 AND using a shielded cable.
 
Not sure that's quite right. These take digital clock and data signals that all share a common ground and convert them into up to four differential balanced low voltage digital pairs over eight wires in twisted pairs for robust transmission over up to several hundred feet. The receiving end unbalances and buffers the four signals providing a new common ground replica of the original signals. So connections both into and out of each are single ended digital clock or data, but the transmission is in fact balanced. Sort of the whole point of the things.
 
Member
Joined 2007
Paid Member
Ah, yes that is true. But in the end it is only usable as SE. For my needs It is fine as I will feed these signals into TVC which can do the SE to Balanced. It's nice that it is buffered does it also increase the signal level?

The digital output is either 3.3v or zero, of course, but the buffering helps drive it into lower impedance environments.
 
I have a wiring question.

I am buffering eight channels of I2S with four Teleporters. It would be very convenient to stack them and buss the clocks, power and grounds. Of course this would create a different length signal path to each Teleporter. My assumption is that while it is important to maintain consistent length data and clock signal lines to each individual Teleporter, the differences between Teleportes would be less significant. My thought is to trim the length of the individual data lines to match the total length of the clock lines including the bussing. Assuming the shared clock signals attach in the middle of the stack the data lines for the top and bottom Teleporters would simply be longer by the added length of the buss wire to insure that all signals arrive as synchronously to each Teleporter. Any thoughts about this or should I star equal length wires from the multichannel XMOS to each Teleporter?

Thoughts?
 
I have a wiring question.

I am buffering eight channels of I2S with four Teleporters. It would be very convenient to stack them and buss the clocks, power and grounds. Of course this would create a different length signal path to each Teleporter. My assumption is that while it is important to maintain consistent length data and clock signal lines to each individual Teleporter, the differences between Teleportes would be less significant. My thought is to trim the length of the individual data lines to match the total length of the clock lines including the bussing. Assuming the shared clock signals attach in the middle of the stack the data lines for the top and bottom Teleporters would simply be longer by the added length of the buss wire to insure that all signals arrive as synchronously to each Teleporter. Any thoughts about this or should I star equal length wires from the multichannel XMOS to each Teleporter?

Thoughts?

I've never really bought into the I2S line length thing, except for keeping them short to prevent noise.

Timing-wise, it is not really an issue... electrons move pretty fast. Traversing transistors (logic gates, etc) can be an issue with timing, but for wiring, I would keep them as short as you can and away from power/gnd leads and be happy.
 
I am buffering eight channels of I2S with four Teleporters. It would be very convenient to stack them and buss the clocks, power and grounds. Of course this would create a different length signal path to each Teleporter...or should I star equal length wires from the multichannel XMOS to each Teleporter?

Thoughts?

I have done such a buss arrangement and it worked fine. As Brian said, the main issue with I2S is wire length (short as poss) and positioning away from interference.

BTW you only need 6 lines for 8 channel so you only need 1.5 Teleporters each end to do this - unless you are feeding multiple DACs that can't be positioned closely of course. I attempted the latter but ran into problems with interference when lights/washing machine/dryer etc were switched on/off (even with shielded cabling). I eventually gave up and use AVB over Ethernet instead (which is far more flexible - you can run it over an existing network). Unfortunately AVB never took off as it requires special Ethernet switching to prioritise real-time traffic, but I still think its the best DIY solution out there for transmitting high quality audio any distance (Dante is expensive, proprietary, and DIY modules aren't reasdily available)
 
Thanks for the replies. They are distantly spaced DACs. I have also experianced dropouts from lights and the electric stove. Running a power extension from the receiver to the transmitter so there is a direct common ground and using cat 6 cable seems to have done the trick. Unfortunately AVB doesn't support 32 bit and is a much more elaborate and expensive solution. Why 32 bit you may ask? The digital EQ and crossover uses up 5 bits as there is a little over 24 db variance between drivers. Then the overall listening level is typically -36db or another 6 bits. Add 3 bits to preserve the resolution from creating all new data and 1.5 bits for dither and its transparent on a 16 bit original with 1/2 a bit to spare.
 
...Why 32 bit you may ask? The digital EQ and crossover uses up 5 bits as there is a little over 24 db variance between drivers. Then the overall listening level is typically -36db or another 6 bits. Add 3 bits to preserve the resolution from creating all new data and 1.5 bits for dither and its transparent on a 16 bit original with 1/2 a bit to spare.

If you do the digital xover/eq volume control after transmission you can get the same quality result using a 32 bit Sharc processor and the Sabre's volume control (I use MQTT/WiFi and an arduino to sync settings in my quad monoblocks).

But yes, using teleporters is way less complex and cheaper if you can resolve the glitch issue :). I wanted to use my system for musical instruments as well so AVB was worth it for me.
 
I hope this is a new question...

I have a new DAC that's made by PS Audio. 2 of the inputs are I2S using older LVDS chips.

I'm hoping I can install a Teleporter in my CD player to connect it to the PS Audio DAC I2S in. But I noticed the Teleporter uses an MLVDS chip which has higher voltage swings and different offsets than the older LVDS drivers. Will it work with my PS Audio DAC? Will it damage anything if I try?

Hugh
 
Member
Joined 2007
Paid Member
I hope this is a new question...

I have a new DAC that's made by PS Audio. 2 of the inputs are I2S using older LVDS chips.

I'm hoping I can install a Teleporter in my CD player to connect it to the PS Audio DAC I2S in. But I noticed the Teleporter uses an MLVDS chip which has higher voltage swings and different offsets than the older LVDS drivers. Will it work with my PS Audio DAC? Will it damage anything if I try?

Hugh
Good and new question. Thus, I would not expect a lot of general knowledge nor experience to help you. I would pull together the data sheets for the two LVDS chips and look at the minimum and maximum swing for each chip. If the receiving chip can handle the teleporter signal, at least you could directly test. If it seems dangerous, do you have any way to just use a second teleporter with the DAC?