Mod your Beresford 7520

[therockst4r]

Larry, I am not sure exactly what your problem is. Could you please clarify what exactly your problem is?

[larry]

Hi,

I have 2 THS4032 installed on my TC 7520. I brought is on eBay from tirna electronic. I am using the build in headphone amp to drive HD600. When lisenting at low volume at 9 o'clock. There is noticetable distortin in the sound. It seem to be unstable to me. But when listening at a higher volume. let's say 11 o'clock. The distorion is minimise but the distortion is still there but less noticetable. I try using toslink(desktop pc) and USB(netbook) both have the same problem, meaning my source is ok. So what is the real problem I have?

[StanleyB]

I happen to have a few THS4032 opamps and decided to test each one of them.
I get a nasty sounding break up of the sound on one, but it is OK on the others. So I reckon that one of my THS4032 is duff.

I would suggest that you try one THS4032 at a time and see if both of them produce the same distortion. That would tell you if one is dodgy.

STan

[larry]

Hi,

I have try installed 4032 on the line and 5532 on head and listen sound normal. Follow by 5532 on line and 4032 on head and it sound normal too.
I do this test for the 2 4032 chip. when even I put both together the distortion come.

[StanleyB]

In that case I would use only one THS4032/ Get a LM4562NA to partner it. I got a few, so you can PM me if you can't buy just one piece off eBay.
I personally think two of the THS4032 in the DAC is over powering. On my system it sounds far too cramped. That's why I use the LM4562 to balance it out.

Stan

[larry]

Hi Stan,

Oh I see, I have a few question. Hope it is not too much =D

1) If I choose to install a 4562, How does 4562 on line and 4032 on head compare to 4032 on line and 4562 on head in your opinion?

2) I have read that installing a 4562 is better to have the surrounding cap remove, what is the different with the surrounding cap remove or not?

3) If you recommend to put 4562 on the line with cap remove, then the MLC5/6 is to be remove?

4) If I have 4562 on the head, which cap do I actually remove?

I saw two 4562 at different price. So which is the correct one?
http://sg.farnell.com/jsp/search/bro...questid=577440

[StanleyB]

There are no hard and fast rules. But the THS4032 needs the caps next to it on the PCB, unless you want a lot of RF break through.

As for the price of the LM4562NA. If it is £5 or less, then you can't complain.

STan

[therockst4r]

Would it be possible to replace the DAC chip with a AK4396?

[StanleyB]

No, but why would you want to go down market with the DAC chip?

[therockst4r]

One of my friends recommended that DAC chip, so I just thought I'd ask.