[Newk Yuler]

Quote:

Originally Posted by PatOMalley /img/forum/go_quote.gif You see the output caps where you have the wires going to + and - ?

Heh... Won't be long before all the stragglers on the Valab thread come over here because you guys abandoned that thread....

 

[MikeW]

I read these teflons can take 600 hrs to fully burn in, does anyone know when they start to "open up" how long until I can expect them to be fairly stable. Im trying not to judge them yet, as they only have about 40 hrs burn in.

 

[PatOMalley]

the larger values up to .1uF can take a month of continuous playing to settle but the smaller values of like .015uF make their impression right away and don't go really negative. What they do is over time they sort of disappear. Meaning the sparkle you notice at first, the increase in obvious dynamics, is replaced by just clean extension.

I never counted the time on the small ones because I like they way they sound at startup and they start to change as I start to get tired of their initial obviousness/distraction.

Nothing does cymbals like Teflon. Or things that go clackity clack.

 

[Wood]

Quote:

Originally Posted by MikeW /img/forum/go_quote.gif I read these teflons can take 600 hrs to fully burn in, does anyone know when they start to "open up" how long until I can expect them to be fairly stable. Im trying not to judge them yet, as they only have about 40 hrs burn in.

Don't know where this came from but I found it to be pretty accurate Mike.



'Teflon capacitors take a solid 400 hours to reach about 90% of their true potential and their true colors open up at the 600 hour mark (25 days). It has also been established that they will even continue to change, ever so slightly, up to 1200 hours (50 days). You may not notice these changes and I only mention it to give you an indication of the characteristics of Teflon.

During the break-in cycle of these capacitors, they will go through different stages. During the initial 150 hours (6 days) , you will notice these capacitors will do a two steps forward, one step back routine. What you will notice is that one day you system may sound fine while the next day (after it's one step back) it will not sound as good as it did even the day before. This is the stage where the capacitors can actually sound broken. Don't be alarmed, it's simply the nature of Teflon.

What you will notice is a 2 dimensional sound. The bass may be uncontrolled, the midrange a bit foggy and a lack of air and extension. Absolutely no coherency.

After 150 hours (6 days), the capacitors start to stabilize. From this point onward, they will be more consistent in their progress. They will still only be at about 50% of their sonic potential but the one step back issue is gone. This stage will last to about the 200-250 hour mark (8-10 days). This is where they start to become more 'listenable' but you are till only half way there.

The bass should start getting better here and the highs a bit more extended but the midrange is not quite there yet.

Now that you have gone through the ugly stages and have reached the 300 hour mark (12 days), things are starting to come into focus. Teflon capacitors start coming into their own between 300 and 400 hours (12-16 days). You may still noticed a few quirks but they should be minimal at this point. You have have more control down below, the midrange is becoming more real and the upper end is starting to extend further. This is when I usually receive the phone calls telling me I was absolutely correct about what to expect.

One you reach the 400 hour mark (16 days), you are starting to reach sonic nirvana and it will not be long before you are experiencing the truest potential of Teflon capacitors. It's been a long road but you will probably find the journey well worth it. This is the point where the midrange magic is apparent. You should notice a sense of texture and realism that is uncanny. The bass is quick and firm and the highs extended with a great sense of air. You will now start realizing a wide, spacious presentation as well. At this point, I don't receive any phone calls at all as you will be too involved in your music to want to waste time talking to me.

After 400 hours........... Heaven.'

 

[PatOMalley]

Burn Notice

For me I have not yet heard a cap that changed into something completely different from what I might expect when I heard it at startup. Yeah, it opens up, loses sludge, drops some edge, but I can tell right off what the character of the thing is.

 

[skibum]

Sorry to intrude but it appears the VALAB thread is about dead.....

I have 340 Ohm Texas Component resistors installed in my VALAB 3.0 and my output voltage is very low. I have adjusted the blue variable resistor for maximum output but it is still VERY low.

What options do I have to get more output voltage out of my VALAB?

Thanks as always,

Skibum

 

[MikeW]

We need numbers skibum. Do you have a Multimeter you could use to get a voltage reading on the output of the dac? It should be around 1.8-2.0 volts AC.

The only thing that effects output voltage, to my knowledge is, the variable resister, the voltage the dac chips are running at, and how many dac chips there are.

Be careful with the variable resister, you can damage it by turning it to many times in one direction.

 

[skibum]

Quote:

Originally Posted by MikeW /img/forum/go_quote.gif We need numbers skibum. Do you have a Multimeter you could use to get a voltage reading on the output of the dac? It should be around 1.8-2.0 volts AC. The only thing that effects output voltage, to my knowledge is, the variable resister, the voltage the dac chips are running at, and how many dac chips there are. Be careful with the variable resister, you can damage it by turning it to many times in one direction.

Yes I have a multimeter. So should I send something like a 1 kHz signal at 0 dB (I have that in a file) through and measure that? Where is the best place to probe? I currently have the digital output of a Squeezebox connected to my VALAB. The output level is variable on that - I will set that to maximum.

 

[MikeW]

I normally take the measurement at 40 hrz, and it's around 1.8-2.0 volts. I connect my leads to the ground connection and the primary, with the dac open, directly from the RCA jacks.

Definately max the volume on the Squeezebox, it's not good to "Digitally Attenuate" the signal before it reaches the dac, you lose bit's (detail, resolution) this way.

 

[errnst]

wood ----thanks for that detailed description of teflon burn-in

 

[Wood]

Quote:

Originally Posted by errnst /img/forum/go_quote.gif wood ----thanks for that detailed description of teflon burn-in

Happy to oblige

Just got back from a classical concert, and found that some of the problems I thought I had, like dry sound, not enough colour were not problems. The SQ of this dac is actualy very like real life. Limitations are really elsewhere, like not having a listing room the size of a concert hall, and not having 40 speakers playing just one instrument each.

Real life suffers from muddiness in the midrange, and not enough tightness on acoustic bass, timpany is a touch boomy and muddy, its very hard to seperate individual violins with your ears, even when you looking straight at them. And yes indeed some dryness at the top end. Odd.

But one thing for sure is the musical enjoyment of live performance gives no more then what this dac puts out. Remarkable!

So all this modding is just about trying to recreate a clone of the 'original', but all the time the ability to comunicate performance was already here, in the stock dac.

I will still continue to 'perfect' this dac, but really its was already doing whats important despite my fiddling.

Its win win, thanks Teradak

 

[PatOMalley]

In certain ways the DAC is better/different in that you get closer, little better on inner detail, can hear voices so close and intimate.

Live performance has the gestalt, the event, the atmosphere which can not be reproduced. As Hegel would have it phenomenologically, a live performance provides an authentic being towards music.

But take some Lycergic-DAC and you virtually get the same head. ... in-authentically. But who's counting?

 

[qusp]

there is an interesting surprise from one of our favorite companies all set to take the world by storm. I have ordered some already. VCAP CuTF copper with teflon filml caps. mine are on their way, i'm a good customer of theirs so I got in on the prerelease. personally I cant think of a better idea for a capacitor. thought some of you guys with big commitment and devoted pocket-books might be keen

 

[Bill Allen]

Quote:

Originally Posted by PatOMalley /img/forum/go_quote.gif But take some Lycergic-DAC and you virtually get the same head. ... in-authentically. But who's counting?

Ok I have to bite after that comment; it just made me laugh out loud. Good one Pat!

Speaking of natural and organic, until you put in Dueland VSF coupling caps & naked foil resistors you are just hearing shades of live IMO. Add to that the "new" Pace Car USB/Mac Mini SSD/Amarra/All Silver TVC preamp & wiring/ all Silver SET amp/ open baffle speakers and “everything” comes alive, real trippy. Or more correctly with most distortions out of the way ... what remains is just the music … and therein lies the magic!

On my forum sabbatical I have had an epiphany that stereo systems are nothing more than music signals mixed with various forms of distortions that we cook to sound pleasing to our ears. (Lysergic soup if you will)

While I understand everyone is limited by their understanding, gear on hand, how much time they have to play, and what they can afford to spend. For gods sakes take some time to smell the roses, get out of the house and go listen to some live acoustic music to tune you ears to. (Nice one Woody) Without a reference we are all just solo tripping.

A quality audio system is a lifetime achievement, and until you "DIY" rather than "buy and try" can you really call this a hobby.

FOR THOSE ABOUT TO DAC ... I SALUTE YOU!

Seriously there is not a better place to start down the DIY path than on this Chameleon DAC. Digital input jitter aside, all we are doing is tuning an amplifier. Yes the Chameleon DAC is an amp ... the source amp. It's the start of everything. IMO the source should be pure just like water. Not distilled, but mountain pure, with nice little organic bits suspended in solution. No man made by-products if you will … distortions, jitter.

Getting your Chameleon DAC "amp" mountain pure is as simple as adding Dueland caps and the naked foil resistors.

Current delivery to the DAC chips is fine at 7.95 volts with 180 ohms I/V resistors. (Yes some hot recording may clip, that's not worth focusing on, just don't take your Porsche down a gravel road) Want more power under the hood, add the Black Gate FK's while they are still available. Want turbo add the FRM mod, the generic brand is the recycled Wima's. Want a different engine, go ahead and mess/replace the power supply. Just make sure you pack your holy water because you'll need it.

The biggest fish to fry on the DAC front however is input jitter and here things get really squirrely, you just can't beat the Pace Car "USB" IMO. I am having Steve Nugent couple my Pace Car I2S direct to the DAC board, the main board will now be completely removed. A seriously lower cost alternative is the M2Tech high face at $150. If we could Mod it to output I2S direct to the DAC board then we could hit the big leagues. Better yet would be for TeraDak to offer a new M2Tech I2S module to plug in.
Hint, Hint!

Digital I2S termination is very tricky and probably the main reason it never became a standard. Depending on length of circuit path, type/impedance of wire and god knows what else the termination resistors change. On the Chameleon the I2S path changes length depending on if the upsampling board is installed. Not good, as are the jumpers like some of you have already discovered. While we have total control over the analog output signal, modding the digital input circuitry is a potential minefield. For example on the Chameleon DAC they are now using Voltage termination, that's what the 5 volt input to the DAC board is all about. It runs voltage to the I2S bus via 3 input resistors and terminates to ground at the last DAC chip via 3 additional resistors. Talk about adding dirt to your source, this circuit was not there on the original Valab DAC's. Kind of a brute force way to terminate when you have varied sampling rates and I2S circuit paths. Not good.

What to do, what to do. As I have said in the past this is best left to the experts in the field. So I have asked Steve Nugent to take a look at perhaps a better I2S termination solution for the Chameleon DAC with the upsampling card installed. If you take the card out then and all bets are off as this is the lowest jitter solution with the stock Chameleon. Notice the signal does not travel through the jumpers with the card in.

TeraDak is simply reacting to customer feedback, you want multiple input interface, reclocking jitter reduction, gravel road protection, and you want it all delivered for $400. I am sorry it’s just not possible without some small digital compromises or a kilo of money. Would I like to see an M2Tech I2S dedicated input version, hell yes. Ok then who out there is ready to tackle the minefield of computer audio USB only input. (Can you hear Yoda talking, 'Go there, I can not, find what you are looking for, you will … !’)

Damn, you are all lucky I am just high on caffeine.

My point being, like Tony said earlier in this post, focus on the things that you can change first. You really need a good basic understanding of Physics to propel your system forward. I use the gear I use today because I have been seriously dabbling with this hobby for 30 years and studied Physics along the way. (Not engineering, it will only box you in). It took me a long time to understand that simplicity is the key; however something’s are not so simple to comprehend, to build, and to enjoy. That’s just the way this universe operates. Take a look at the components I use above, they are working with the force, not against it.

Perhaps I will start an online Jedi audio training course to navigate the cryptic minefields that plague this industry. Getting your information from the forums is like drinking water from the toilet bowl at a petrol station. Then again that doesn’t stop my dog from that course of action … and he is as healthy as a horse.

(‘Know what I am talking about, do you? Hmmm...?')

 

[PatOMalley]

A real act of commitment: I moved Bud Purvine's magic ground wire from my VALAB to my Chameleon.

For some info on how this may sound check out this review @ 6moons The RCA version would be germane here.

For me there is more inner detail like the sound of tremolo on voices, trailing transients, stuff like that. EDIT: and more richness & depth across the board, as well.