I have managed to get my Windows 10 machine to talk to the DAM1941.
I purchased a new USB to TTL serial adapter which uses the FTDI FT232RL chip, this has drivers compatible with W10, MAC OS X, Linux etc (see the FTDI site).
So drivers loaded, cable plugged in, Windows 10 gave me a connection on COM4, ExtraPutty recognised the DAM1941 - happy me!
I purchased a new USB to TTL serial adapter which uses the FTDI FT232RL chip, this has drivers compatible with W10, MAC OS X, Linux etc (see the FTDI site).
So drivers loaded, cable plugged in, Windows 10 gave me a connection on COM4, ExtraPutty recognised the DAM1941 - happy me!
Soekris,
Just to be on the safe side:
In the manual it is written "...There is no requirement for a specific load, but low impedance loads will reduce the output voltage."
So, a small impedance like 10 ohm or 20 ohm is fine as well ? Reason I ask is that I use a tube output stage to get to 15Vpp output. Not sure what the right impedance to get toright voltage level will ne, ne I do not want to damage the 1941with a too low load.
Just to be on the safe side:
In the manual it is written "...There is no requirement for a specific load, but low impedance loads will reduce the output voltage."
So, a small impedance like 10 ohm or 20 ohm is fine as well ? Reason I ask is that I use a tube output stage to get to 15Vpp output. Not sure what the right impedance to get toright voltage level will ne, ne I do not want to damage the 1941with a too low load.
The output is really a voltage source with a output impedance of 625R per resistor network string.... You can parallel them, you can short them to ground, which is what my mute jfets are doing, it doesn't matter, no damage. Output voltage will of cource be much lower into that low load, ohms law do apply.
But why a low impedance load ? You can connect the outputs directly to tube grids....
But why a low impedance load ? You can connect the outputs directly to tube grids....
I will connect them directly, but the input signal needs tobe attenuated to approx. 0,6V in order not to have a too high signal atthe end of the tibe stage...I just wanted to be sure I can use your dac basically like the buffalo-III whichis driving it now...will be very interesting to compare...i am very excited...
Mine is working now (USB-Input) without any issues right from the start...how great is that ? IN the end I have now used 1.1k grid-to-ground before it goes into Dfferential stage of the 801A and LL1692A OPT, so a very high resolving DHT output stage.
I need to align the levels between the BIII and the Dam1941 before getting into serious listening tests plus I will give the DAM a week burn-in (24h/day) before really comparing.
The nice thing is that I can switch the output-stage via connectors and bring both DACs to the exact same output-level.
My very first impression:
- Both play different with their own character, it is less about better or worse, it is more about do you prefer tonight St. Emilion with high Merlot percentage or St. Julien with high Cabernet percentage.
- The Dam1941 seems to have more macro-dyamic, brutal force in the bass region, really great. No doubt about rhythmn. Really impressive.
- The BIII (dual Mono) seems to have a finer treble region, more micro-dynamics, simply finer structures.
- Tonal wise / tone colours the DAM seem to be more natural and "fuller", I like the body of instruments.
- Clarity is excellent in both. No comparison to normal DACs you would buy in a shop with their OP-amps in the output.
I will burn it in for a week now, measure the level of both and adjust the resistor network to ground at the tube grid to have both at the same level and than serious listening will start....
By the way: My BIII is pretty much tweaked out: Shunt-Regs, Dual Mono-Psu,Ian's fifo2, pulsar clocks, WaveIO etcetc...so not completely fair comparison...given this effort, the DAM is really unbelievable easy to implement and so much cheaper.
I need to align the levels between the BIII and the Dam1941 before getting into serious listening tests plus I will give the DAM a week burn-in (24h/day) before really comparing.
The nice thing is that I can switch the output-stage via connectors and bring both DACs to the exact same output-level.
My very first impression:
- Both play different with their own character, it is less about better or worse, it is more about do you prefer tonight St. Emilion with high Merlot percentage or St. Julien with high Cabernet percentage.
- The Dam1941 seems to have more macro-dyamic, brutal force in the bass region, really great. No doubt about rhythmn. Really impressive.
- The BIII (dual Mono) seems to have a finer treble region, more micro-dynamics, simply finer structures.
- Tonal wise / tone colours the DAM seem to be more natural and "fuller", I like the body of instruments.
- Clarity is excellent in both. No comparison to normal DACs you would buy in a shop with their OP-amps in the output.
I will burn it in for a week now, measure the level of both and adjust the resistor network to ground at the tube grid to have both at the same level and than serious listening will start....
By the way: My BIII is pretty much tweaked out: Shunt-Regs, Dual Mono-Psu,Ian's fifo2, pulsar clocks, WaveIO etcetc...so not completely fair comparison...given this effort, the DAM is really unbelievable easy to implement and so much cheaper.
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Thank you for your report Blitz
If i had to compare mine: ESS vs 1021, it would read similar, minus the "brutal force in the bass region", so i guess an out of the box 1941 is already better than a tweaked out 1021 at least in this area.
As USB/i2s convertors may sound dramatically different it would be interesting id you get the chance to use the same with both dacs using the newly operational i2s port. Unless it is too much trouble.
If i had to compare mine: ESS vs 1021, it would read similar, minus the "brutal force in the bass region", so i guess an out of the box 1941 is already better than a tweaked out 1021 at least in this area.
As USB/i2s convertors may sound dramatically different it would be interesting id you get the chance to use the same with both dacs using the newly operational i2s port. Unless it is too much trouble.
Well...both use an Xmos chip, waveio and the Dam...nevertheless, there is nothing done than unpacking it and put the standard power board in place, which is basically 7805 stuff, so the most standard power suppy you can think of....a lot of tuning fun alone there...
I will enable the 1.24 firmware and the second i2s port in the future and will feed the DAM what comes out Ian's fifo2...I know normally youwould think a fifo before a fifo ? waste of money. But it is already here and why not giving the DAM the same data quality as the buffalo ?
Than there is the filter topic...I guess there are filters which sound more robust like the standard out of the box and maybe others which give more resolultion in the trebles ? and hints are welcome.
Last but not least, are there any analog filters in the output to filter nasty HF stuff as some DACs used to have ? Maybe there is as well an opportunity to gove the trebles a little bit more life....as we talk not about more trebles, it is more about the fine vibrations of a cymbal which sound more realistic on the ESS...
I will enable the 1.24 firmware and the second i2s port in the future and will feed the DAM what comes out Ian's fifo2...I know normally youwould think a fifo before a fifo ? waste of money. But it is already here and why not giving the DAM the same data quality as the buffalo ?
Than there is the filter topic...I guess there are filters which sound more robust like the standard out of the box and maybe others which give more resolultion in the trebles ? and hints are welcome.
Last but not least, are there any analog filters in the output to filter nasty HF stuff as some DACs used to have ? Maybe there is as well an opportunity to gove the trebles a little bit more life....as we talk not about more trebles, it is more about the fine vibrations of a cymbal which sound more realistic on the ESS...
Some optimistic assumptions why this should not matter seem to have been made...
I doubt there is filtration other than a horrid pF ceramic right at the output. Best removed, not much point replacing it knowing what you have downstream.
Interestingly i tried the fifo at the input and did not like it much. Weird.
I have some different PSUs to try...by the way: are there any insides regarding on-board regs of the 1941 ? I guess there are some ?
By the way...is there any documentation on what you can control using the display board ? Can I select the digital filters there or do I need always to use the umanager ?
By the way...is there any documentation on what you can control using the display board ? Can I select the digital filters there or do I need always to use the umanager ?
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Doublechecked the wiring and tested the I2S signal with a dam 1021.
- The I2S signal works with the dam 1021.
- No lock with the dam1941
Don´t know where to search next to get the I2S port work.
Hope the firmware update worked well (see attachement)
Attachments
It do look like that the fpga firmware is an old version, something must have gone wrong merging and moving the files....
A correct 1.23 is now on the website, please try again.
At least the second I2S port is working as expected
The FPGA firmware is now 1.23 too.
Attachments
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Hi, somehow I'm a bit unsure now ... I follow this discussion for a while and actually thought I had read all posts. Obviously I have read something over. The second I2S input works with the fw 1.23? I thought the current fw is 1.23 and sören is working on the 1.24, with the second input should work then. Can someone clarify that - maybe the developer will say a clarifying word!