Chameleon DAC listening and modifications - Page 8

Hi

Welcome Chris, look forward to your contribution!

I do notice more Hiss on this chameleon then my old valab had. Im hoping it clears up a little with break in. In my 2.1 I get hiss but not until the volume is up to unlistenable levels. I can hear it more easily on Chameleon, at loud but not crazy volumes, at the volumes you listen to Classical at.

Hey Bill, hows your power supply holding up? Have you done anything to it other then put big feet? It sounds like a nice mod, but I really hate to ugly up this nice chassis with holes, guess I could try to find a local machine shop that could do it pretty. Not doing anything for a couple weeks though, perhaps longer. Not by choice though, I lost my job today (laid off), yet again. It's not a good time to be a Locksmith in San Antonio. Tax time is coming, really puts the crunch on small business.

Edit: I had the combo Stacked and recently took them apart, they run much cooler this way. Especially the Dac, I was experimenting with this, thinking maybe the heat from the DC-30 would transfer to the Dac and it would act as a larger surface area to keep the whole thing cooler. Does not seem to work that way though, ashame as the pair looks excellent stacked.

MikeW, sorry to hear about your job, hope all goes well soon... I have my DC-30W yellow wire running without issues and DAC voltage at 7.85VDC..

Hi Mike,

What do you exactly mean with hiss? Do you mean noise? Assuming you do:
You are right that the Chameleon is more noisy and this is explicable because we are now listening to 16 paralleled DAC chips, all with their own noise floor. In the previous post you can see that it has a signal to noise ratio of -78dBu. If I recall correctly the Valab has a signal to noise ratio of approx. -85dB (unmodded) and is a few dB's quieter with a very low noise power supply.
I would use the word hiss when there would be a (distortion) problem with the high frequencies which are 'smearing' more (making a 'sss' sound instead of a single 's')
If you indeed mean hiss then I can't give you a proper answer yet: At the moment my Chameleon has been on for 8 hours or so and although it does sound better than the Valab in stock form it is not coming even close to my modded Valab. But I won't give a judgement until It's fully burned in.

Dream?

If by your modded Valab, you mean your dreamdac, tour de force, that stunned us all, then I am not suprised.

Looking forward though, to the dreamdac2

Not talking about sibilance Rhodes, but the noise you get when there's no music playing and you crank up the volume. I somehow had the expectation that this would be less then the old valab not more. Is there anything that can be done to make it a little quieter? some kind of bypass or filter cap maybe (without destroying the music in the process). I can live with it, but would be more satisfied if it was not there.

There's not much you can do about it except a few things:
1. Be sure your 115V or 230V source is clean. A good power filter really helps. It first of all makes your equipment sound (much) better and it will also reduce noise.
2. The power supply. The lower the noise and ripple of the supply, the better.
3. Connect your 115V/230V power cable the correct way in the power point. This also helps.

I think the noise floor of my Valab went down with 4 or 5 dB when connected to a clean power source and my Paul Hynes design power supply.
For your records: every 6 dB is twice as loud (or softer) for the human ear which means that bringing down the noisefloor with 4 or 5 dB is quite a lot..

LOl Thanks. The Dreamdac 2 is planned but won't see the daylight before may or june I think.

After serious listening to the Chameleon tonight I came to the conclusion that it definitely has the capability to be a big big winner.
The soundstage is already very good by the way. Just out of the box and unmodded it is already almost as huge as the fully modded Valab. The only difference is that the Chameleons stage is still blurry but i'm sure that will dissapear once burned in and modded.

I already love this DAC, despite of the hum.

yeah I believe in power conditioning, I use a PS Audio Duet /w decent quality power cords. The Duet is not the be all end all, but it's no slouch either. Guess i'll just have to resign myself to it. Can anyone else confirm more noise then the old valab? Before on my amp's volume pot, I started getting noticeable noise around 1 o'clock now it's there at 11. The amp itself has a much lower noise floor, I can barely hear hiss with the volume at 100%, when nothing is attached. Guess it just gives more of that record-like nos flavor lol

I wonder where your hum is coming from? Is it the transformer itself? I saw where you said there was some AC on the DC line.

Hey guys please try a simple experiment for me -:

Lift one leg from each of he 2 large brown .01uf Chiclet looking caps on the DAC board, take a listen and tell me what you think.

I hate to play devils advocate, but it takes some ears to notice a change like that. Just one RCA jack? on your transport? Really?

That is not just one jack, it has at least four electrical connections that potentially are crap (most manufacturers of consumer electronics do not care about this sort of sound quality tweaking unless they can sell it as a feature). Just a different piece of wire, just one resistor, it adds up.....also for the devil and his advocate ;-)