Gator aid. Or how to get the most from your Gator.

[chrism]

Just check the voltage at each Murata poition as you need a voltage differential through the regulator. The 5v one should be fine but just check the 12v one. If you only have 12v to it and 12v out it may cause the noise you are hearing.

Regards

[maniac]

Just check the voltage at each Murata poition as you need a voltage differential through the regulator. The 5v one should be fine but just check the 12v one. If you only have 12v to it and 12v out it may cause the noise you are hearing.

Regards

Hi chrism, you mean during caiman powered up and fed with signal to use the voltmeter to measure voltages between GND and Vin and then between GND and Vout, right? I'll do that this afternoon, thank you!

[maniac]

For the burson, I think M. Beresford didnt recommand using bursons in its dac because they need -15/+15 power supply to work properly. I made a separate PS for it, that's why I use it in the caiman. The Burson is plugged in the socket using a bent extension, so the lid is closed. It was actually used in my previous dac, and I couldn't stand not using it in the beresford.

If you tried the passive output mod, I would say that the burson as headphone opmap brings the headphones output to nearly the same level of truth / dynamics / impact / lifelike reproduction, but that's just my perception trough my own ears

Anthony

Hi Anthony thank you!
I can see that you are using original module, just the headphone opamp replaced wit Burson. With this board and standard opamp I'm not hearing the background tone. I can hear it only with Gator module http://www.beresford.me/products/GatorEU.html .


I'll first try to measure voltage on regs as suggested by chrism then start to think about shortening power cable or adding 330uF cap to murata.

[chrism]

Hi Anthony thank you!
I can see that you are using original module, just the headphone opamp replaced wit Burson. With this board and standard opamp I'm not hearing the background tone. I can hear it only with Gator module http://www.beresford.me/products/GatorEU.html .


I'll first try to measure voltage on regs as suggested by chrism then start to think about shortening power cable or adding 330uF cap to murata.

Sorry to appear to be clever but take care when touching the pins with the multimeter probes - don't short anything or you will be really cross with me!

I had a strange noise with my Caiman when changing PSU's as the voltage was not high enough into the 12v Murata (I only had about 13v in to it).

This is one of the reasons why I went for two PSU's and scrapped the internal regs completely but that's another story.

Regards

[maniac]

Sorry to appear to be clever but take care when touching the pins with the multimeter probes - don't short anything or you will be really cross with me!

I had a strange noise with my Caiman when changing PSU's as the voltage was not high enough into the 12v Murata (I only had about 13v in to it).

This is one of the reasons why I went for two PSU's and scrapped the internal regs completely but that's another story.

Regards

Thanks for notice - this was really delicate task to not shorten anything
Here are my measurements:

12V reg: input=14.76V output=11.98V
5V reg: input=14.75V output=5.00V

Should be 14.76V on 12V input be enough? I'm not quite sure if 11.98V on output is OK, but could be also my cheapo multimeter not measuring 100% correct..

[chrism]

The measurements are spot on so this is not the cause of the problem. I must say though in general that the Murata 12v data sheet infers that a little more headroom on the input is desirable.

I will have another think about what to test next.

Regards

[maniac]

My mistake, it's 70 cm long, corrected in my previous post (I definitly have to read my posts before sending them).

I soldered a spare 330uF elna silmic II 25V ( but 16V will be fine), soldered directly the first reg pin and ground of the output cap. I must confess I'm not sure it is the root cause of the problem, as I am not a electronics expert, but adding this cap solved the problem for me.

As I have no 330uF caps I've just applied 220uF 25V caps to both 5V and 12V regs because applying to just either one did not removed noise enough.

Now the 964Hz noise is nearly completely removed as also can be seen on this recording of pink noise I've made after applying the caps.



Now I would be really interested if people with Gator and Murata regs with default caiman power supply have the same issue as I had

Photo with caps on Muratas installed:


One thing telling me that this is just a workaround and not really solved is that now when listening to headphones with volume know on VERY low level i can hear quite loud high frequency tone in headphones. But i'm not listening to headphones on such very low volume levels, so not a big deal for me.

[dthp]

One thing telling me that this is just a workaround and not really solved is that now when listening to headphones with volume know on VERY low level i can hear quite loud high frequency tone in headphones. But i'm not listening to headphones on such very low volume levels, so not a big deal for me.

Glad It worked for you. I would be surprised if we were only two having had this issue.
I think the low volume noise is an other issue, not linked to the murata. I actually met the same noise with a 32ohms generic headphone, but it has completely disappeared with my 62ohms K701, so I didn't go further.

Anthony

[Recoil]

Stan, any idea on the hiss issues?

[StanleyB]

Stan, any idea on the hiss issues?

If you have a hiss issue, email me and we'll go through it . In which thread did you mention that you had a hiss?