Murata regs + Caiman = Problem??

[paul_cz]

a hacksaw!!! you make it sound so cheap and brutal. I am sure that it was done with a delicate touch and the use of a fairy's brom

... well, that is my weapon of Choice ;-)

[HighFidelityGuy]

The improvement?
Apart from the obvious removal of the background tone I have a more solid soundstage with better placement.
Also the front to back stuff seems more obvious to me.
Biggest change though (in my system) is that it plays tunes better.
Rythyms flow better, it seems smoother but with more detail?

Maybe the hallmarks of cleaning up the power going to the dac chip?
Dunno..but it works.

I was going to hold back on my comments on sound quality but after doing some listening tonight and then reading the above comments I felt that I ought to chip in and say that I'm hearing pretty much the same improvements. I've got a bigger sound field, more detail and texture but with a smoother presentation that's not fatiguing. I'm finding I can crank the volume a bit more and get a bigger sound without things getting too forced.

I think that some of this will be due to the lower noise floor now that I've not got a constant hiss and whistle muddying everything but I'm surprised by the sound field improvements. I wasn't expecting that, so it's a nice bonus. As I also replaced the ribbon cables with solid silver wire I guess that change could be playing a part in what I'm hearing but I can't be sure. Either way I don't really care as I'm loving the sound I'm getting now, it's definitely the best I've heard from my system yet and with any luck it might improve further over the next week or so as the new bits run in.

So now the only thing I want to do is cool down the 5V reg a bit and I'll be very very happy.

[Gazjam]

Dave?

Ironic thing is that it was you who organised the group buy on the Murata's....
what goes around comes around...

[maniac]

Regarding the Murata background noise, best theory I've heard came from Jimmy Dripps of Tirna (and I no doubt misquote), who thought it was a case of both regulators operating at a frequency too close to each other (just bad luck) and this caused an audible "beat" which manifested itself as the noise.

Hi Gazjam, I'v tried two different pairs of muratas, one pair from Tirna and later one pair directly from US (tried to resolve the whistle), but both pairs had the same issue so it would be quite surprising if in both cases I'd hit some specific frequency. I'll probably try to combine those pairs in between them before buying Dexas if my PCB would allow me to experiment further because I also Melted junctions of PCB for 5v reg already :/
btw I had to replace ribbon wire too, seems to Br quite common issue when modding too much

Tomas

[Gazjam]

Hi Tomas,

Honestly?
I'd go for the Dexa's and be done with it.
They should improve the sound of your Dac as well as removing the whistle noise.

I attempted to fit the Dexa's myself, got as far as being unable to remove the Murata's properly before realising its time to call in an expert!

[HighFidelityGuy]

Dave?

Ironic thing is that it was you who organised the group buy on the Murata's....
what goes around comes around...

Yeah, hindsight's great isn't it. It seemed like a good idea at the time with the info that was available back then. I guess the Murata's turned out to be a bit of a waste of time and money for some people but at least they provided an improvement for a year or so.

I think this experience proves quite well just how difficult it is to choose components that complement each other to produce the best end results in a product. You really can't rely on the spec sheets to tell you how components are going to work together. So I'm now starting to understand why some manufacturers spend years developing some products by trying hundreds of combinations of components until they find the perfect balance. It's more of an art than a science in some ways I guess.

[HighFidelityGuy]

I decided to do some heatsink butchery of my own and took a hacksaw to an old graphics cart. I ended up with some L shaped sections with lots of little fins on the back. Due to the space restrictions around the 5V reg I had to trim that heatsink down quite a lot but I have some small memory chip sinks which I'm going to attach to the main one with thermal adhesive. The 5V reg now runs much cooler so that's put my mind at rest. Here's what it all looks like so far:



The sink on the 12V reg is waaaay bigger than it needs to be and currently obscures one of the screws that secures the PCB to the chassis. So I'm going to tweak that later. As you may have noticed I've removed the two pairs of output connectors. I removed the fixed output a while ago as I wanted to hard wire that output to a short home made silver interconnect that connects to my passive preamp below. I then removed the variable output to make space for the 5V reg's heatsink. I've also removed the headphone output socket to allow me to solder the Gator board in place and I've removed the USB input to make way for an extra optical connector. What with them and all the other mods there's not many original parts left in my Caiman.

[Canetoad]

Dave, when you do replace the USB with a toslink let me know where you sourced the parts. I'm thinking of doing the same thing myself.

I've just replaced the Maplins CB supply on mine with a bespoke PSU I put together myself. I'm running it at 15.8v so that the Dexas should now be getting round 15v. The sound has improved even more! I actually heard something I hadn't heard before on the Steely Dan - Do It Again track. There's definitely extra detail now that the noise floor has obviously improved. Music has more impact and dynamics too. I'm very pleased with my setup now! Even my wife noticed the difference with the new PSU.

I'm going to build another PSU to power my Touch now.

[HighFidelityGuy]

Dave, when you do replace the USB with a toslink let me know where you sourced the parts. I'm thinking of doing the same thing myself.

No probs. I bought some Toslink sockets ages ago to do this but I've just not got round to it. I'm hoping the ones I got are the right ones. I think I got them from Farnell but I'm not sure now. I'll have to check. I think there may be a slight issue with the chassis cut-out for the USB socket being slightly in the wrong place for a Toslink socket but I think it will be easy to get round with a little metal working. I'll let you know how I get on.

[HighFidelityGuy]

Dave, when you do replace the USB with a toslink let me know where you sourced the parts. I'm thinking of doing the same thing myself.

I've just dug out the Toslink socket I have. It's THIS one from Farnell. I'm in the progress of modifying my regulator heatsinks a little more so I'll hopefully install the Toslink socket tomorrow when I build the DAC back up. I'll let you know how I get on.