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Old 3rd October 2010, 03:18 PM   #61
sendler is offline sendler  United States
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Default 2mv

Quote:
Originally Posted by TC Goh View Post
Hi Scott

Hope you are having a good weekend.

The DC offset is set by 2 (5K, I think) variable resistors on each board. So far (touch wood), the offset is close to 0 with a variation of about +/- 2mV but hovers around +/- 1mV most of the time. It doesn’t vary much though, even during use (on my set, at least) but that could be because my Fluke can't detect it! Its resolution is only up to 1 mV.. Ha ha.

I think if it stays within this range, it should be ok, right? Anyway the speakers and amps are still functioning, which is always a good sign.

Oh, OCL is also slightly louder. I guess this is because this is the path of least resistance.

Best wishes

TC
2mv is excellent. Most circuits should have no problem if it stays that low.
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Old 3rd October 2010, 07:58 PM   #62
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Hi TC,

yes, those are line transformers. I put the two Jensen JT-11P-1 to connect the balanced output with the SE input of my DNM pre-amp.

Daniel
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Old 3rd October 2010, 08:02 PM   #63
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The transformers should not affect the sound too much. There is always some loss, and it would be interesting to test further transformers but at the moment I am just happy.
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Old 3rd October 2010, 11:25 PM   #64
TC Goh is offline TC Goh  Hong Kong
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Quote:
Originally Posted by sendler View Post
2mv is excellent. Most circuits should have no problem if it stays that low.
Hi Scott

Thanks.

I guess this will need to be checked regularly like tube biases....

Having said that, there is a circult relay that should prevent DC leaks in the event of an unexpected spike.

Best wishes

TC
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Old 3rd October 2010, 11:43 PM   #65
TC Goh is offline TC Goh  Hong Kong
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Quote:
Originally Posted by c1cc1ccc1 View Post
Hi TC,

yes, those are line transformers. I put the two Jensen JT-11P-1 to connect the balanced output with the SE input of my DNM pre-amp.

Daniel
Quote:
Originally Posted by c1cc1ccc1 View Post
The transformers should not affect the sound too much. There is always some loss, and it would be interesting to test further transformers but at the moment I am just happy.
Hi Daniel

Ah.... I am guessing here again but as you have a balanced set, the line TX are probably to step-down the output from the 3V to 1.5V, right? I actually tried using 3V output feeding my pre-amp's SE RCA and it sounded distorted probably from being overloaded!

Would the dynamic range be still at 133db? If it maxes out at this, then the TX is a wonderful addition as you get the best of both worlds!!!

Best wishes

TC
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Old 7th October 2010, 06:35 AM   #66
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Quote:
Originally Posted by TC Goh View Post
Ah.... I am guessing here again but as you have a balanced set, the line TX are probably to step-down the output from the 3V to 1.5V, right? I actually tried using 3V output feeding my pre-amp's SE RCA and it sounded distorted probably from being overloaded!

Would the dynamic range be still at 133db? If it maxes out at this, then the TX is a wonderful addition as you get the best of both worlds!!!
TC
Hi TC,

not really to step-down, the turns ratio of the TX is 1:1. I need the DAC's output galvanically separated since my preamp is single-ended, so I have different grounds between the source and the sink. With the setup I let the DAC operate into a virtual ground.

I have no problems with distortions but of course there are transformers with different turn ratios that can solve this issue.

To keep the dynamic range you should place the TX as close to the single-ended sink as possible, AFAIK.

(Note that I am not an expert in the field of transformers.)

Regards, Daniel
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Old 7th October 2010, 06:46 PM   #67
sendler is offline sendler  United States
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Default 24/96 usb to I2S converter

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Originally Posted by TC Goh View Post
Hi Scott
Thanks for your reply. I will do more research on e transports.
Here are a couple new 24/96 usb converters to compete with the HiFace.
.
New 24/96 usb converters
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Old 11th October 2010, 06:04 AM   #68
TC Goh is offline TC Goh  Hong Kong
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Quote:
Originally Posted by sendler View Post
Here are a couple new 24/96 usb converters to compete with the HiFace.
.
New 24/96 usb converters
Hi Scott

Looks interesting and this seller is in HK too. That should prove convenient for me Click the image to open in full size..

Wow ...1 ppm clock! I think this should mate well with the 1794A DAC.

The seller also lists some sites where we can get high res 24*96 flies. In a capable system, the music should be great!

I will certainly take a good look at this.

Thanks.

Best wishes

TC
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Old 11th October 2010, 07:33 AM   #69
Calvin is offline Calvin  Germany
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Hi

why settle for 24/96 when You can do 24/192 already?

jauu
Calvin
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Old 12th October 2010, 08:35 AM   #70
skseah is offline skseah  Singapore
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Hi T C,
Finally finished my DAC...now 'burning' it in...initial sound very promising...unfortunately, one of my amp just broke down..so now have to solve the amp before I can listen to DAC. Will try to roll the caps later.
Best Regards
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