The KillerDAC Audio forum

Great resistors, but new they can sound a bit dark for a few days, but clean out nicely, i use them in tuning,  in only the right positions till the balance is right. Let us know what you think of them, but only after run in.

I have been doing some serious listening to Danny's Computer transport and its incredibly clean and clear, You can certainly hear a lack of mechanical noise, and a certain smoothness results. But after listening to the Wadia transport with the vintage chips, the same chips as the marantz 94s ect. These early chips are made like the TDA1541 and it shows. These are bigger than the TDA and have the same kind of lower midrange weight and gut gravel in the voice. They are coarser and a little ruff but so real with real flesh and bone, real body, and most impressive...... Dynamics. Its a shame we can not have the best of both worlds. Pictures of Danny working on the computer transport.

I moved from a PC and DAC to vinyl, and now to a CD player, I'm not in a hurry to move back to PC as a source for similar reasons.

When I used a PC I had what I perceived as a quieter background but I lost something else.

We ran 48kHz into the KillerDac, I have never heard it sound do good. Computer audio has arrived. It just annihilated any computer audio system i have ever heard. No actually it annihilated any front end i have heard. I guess it always should have in theory and it finally did.

I have been doing some serious listening to Danny's Computer transport and its incredibly clean and clear, You can certainly hear a lack of mechanical noise, and a certain smoothness results. But after listening to the Wadia transport with the vintage chips, the same chips as the marantz 94s ect. These early chips are made like the TDA1541 and it shows. These are bigger than the TDA and have the same kind of lower midrange weight and gut gravel in the voice. They are coarser and a little ruff but so real with real flesh and bone, real body, and most impressive...... Dynamics. Its a shame we can not have the best of both worlds. Pictures of Danny working on the computer transport. 

You are not quite understanding how the whole thing works.

As I pointed out in last post, the 'old' JLsounds board (that you have) reclocks all I2S signals with a discrete flip flop chip. From memory it was LVC (but can't recall exactly).

So in fact your I2S lines to DAC have only 1 LVC logic chip between clock and DAC. That's why it sounds so good.  
Given this, the MUX switching chip could well make quite a difference. The only way to know is try.
 
The new board I2S has reclocking inside FPGA chip. I believe they take great care to keep jitter low but it won't be as good as a discrete FF logic chip.

Terry,

I understand exactly what you are saying wrt the differences implemented in the clocking o/p's of the two boards.
I'm not using the old board in this project.
Saving it for something else.

Ideally it would be best to have the USB board mounted right above the TDA1541 and extend the USB port to the rear panel instead but this is a retrofit project and I'm taking into consideration some practicality with the fitout.
Time to enjoy the results, using foobar2000remote on my phone. This is brilliant, it gives you full control of the system and allows full access in to the PC's directory structure. Can play whatever you have on your laptop, maybe network drives too, I will have to check this.

Fun fun fun!

Terry,

The switching of SPDIF & USB feature was implemented purely for convenience as some would still prefer for their DAC to be compatible with legacy SPDIF devices, so that's my thought about that.

Yes, that's right. My point was by having spdif compatibility, you give away some amount of performance in USB mode. The difficult thing with
all this clocking / jitter biz is it's hard to get a perspective on what really matters. We are for the most part just listening which gets really tricky
with jitter. It would be great to have a phase noise test set but that's a lot of money    

In regards to the logic type used, I used HCT series which is what I had available, sure ACT would have been faster but I wasn't going to fuss over a single logic chip when compared with the digital signal traveling through LSI IC's like the Xmos > Xilinx which contains zillons of them.

You are not quite understanding how the whole thing works.

As I pointed out in last post, the 'old' JLsounds board (that you have) reclocks all I2S signals with a discrete flip flop chip. From memory it was LVC (but can't recall exactly).

So in fact your I2S lines to DAC have only 1 LVC logic chip between clock and DAC. That's why it sounds so good.  
Given this, the MUX switching chip could well make quite a difference. The only way to know is try.
 
The new board I2S has reclocking inside FPGA chip. I believe they take great care to keep jitter low but it won't be as good as a discrete FF logic chip.

With regards to the USB bridge, I am using the latest I2SoverUSB v.III board from Lyuben with the Xilinx re-clocking. (I ordered them just a month or two ago, they're a lot more versatile.)

http://jlsounds.com/products.html

I have one of the old boards too which I'm planing for another project.

I've only been able to get the old board working up to 96kHz with the TDA1541. Have you tinkered with these older ones? (using the  TDA1541)

Yes, I've had new and old boards working fine with TDA1541.

You should be able to get 192k / I2S from both and 384k / simultaneous from the new one.
Yep the new one is very flexible for just about any DAC out there.

My aim is to get a PCM1792 running native DSD256 (11MHz) with new board. 

All good fun.

TCD