[Ric Schultz]

Only Quadman has done "most of level one mods"  He has yet to try the WA Quantum Chips but has ordered them, then he will have all of level one mods plus some damping and shielding that he did on his own.  I sent him my digital cable to install (that he modded slightly as it was shorted) and he installed the exact diodes I use...damped the way I suggested.  So far, you guys have done about half of only the AC mods.  You do the rest of the AC mods and you will get another whole level.  What I am doing now is bypassing the entire fuse holder and fuse.  I use the AC receptacle as if it had no fuse in it.  I solder the hot wires from the transformers (white) as close to the incoming hot AC pin as possible.  This sounds even better than a great fuse and holder.  I am also damping the AC receptacle with EAR SD40AL (available from Michael Percy).  I use this same material to damp the two blue caps on the output board (pieces of damping going across the top of the caps and to the side and inside brace of the DAC).  I found the hardwired and damped stock receptacle to be better sounding than the Furutech Fi-10.  More airy and extended.....maybe it is because it has less mass?  Keep tweaking!  It just gets better and better! 

BTW....double layer of cardboard under the trannies sounds much better than one half inch plywood I tried.....also do not tighten the nylon hardware....just use it to keep the transformers from moving around.  You do not need the nylon hardware if you are careful when moving it around.  I have mine without cover (tweak nut that I am) so don't need no stinkin plastic bolts....he he.  I glue (very thin layer of Amazing Goop) two cardboard donuts together and then use thin double stick tape to hold them down lightly to the chassis.

[jtwrace]

I"m pretty sure you're certifiable.      


I sure do hope people don't bypass the fuse which is there to protect them.  That's just asinine to actually encourage that. 

[Ric Schultz]

If people want a fuse, they can have a fuse.....I have no problem with that. 

However, line level transistor gear usually has no more than 50 watt transformers.......the most power you could ever get through them would be to completely short the secondaries.  If you did this then the transformer would maybe draw 1000 watts for a few seconds and not blow your circuit breaker....however, in that same few seconds it would get so hot it would just open a primary winding on the transformer (I know, I have done this).....just a puff of smoke and then nothing.  The primary winding on a small transformer is like 30 gauge wire.....NO flames, no fire.....just a puff of smoke.  The transformer is its own fuse!  Now if you had a rag soaked with gasoline on top while you shorted the secondaries.....you then would certainly get a nice fire.  Most people I know do not have the cover off their equipment and have gasoline soaked rags on their transformers.  Line level transistor gear is very, very free from even ever blowing a fuse.  When is the last time any of you ever heard of anyone who blew a fuse in a transistor line level piece of gear????!!!!????.....really, in nearly 40 years I have never heard of it.  Have you blown a fuse in a transistor DAC, preamp, tuner, CD player, transport?  If you have, you are the first I have even heard of.  Dynaco sold hundreds of thousands? of PAS2/3 tubed preamps that had the power cord soldered directly to the power transformer (before UL ratings obviously).  Don't think they even burned anyones house down.

Most people are way more conservative than me.....however, I feel very confident that having no fuse in a line level (transistor) piece of gear is perfectly safe......I am sure the EEs will have a fit with this statement.....but just try the experiment that I did ....you will see...you cannot start a fire....unless you have extremely flammable material on top of the transformer.

[jtwrace]

unless you have extremely flammable material on top of the transformer.

Cardboard that you're recommending under the transformer is flammable and only gets more flammable with time.   



I'll disagree with everything you wrote above.  It's about safety Ric.  Period. 

[Ric Schultz]

Just try the experiment.  Put an AC current meter on a 50 watt transformer (sitting on cardboard) and also put a temperature sensor on it.  Then short the secondaries and then plug it directly into the wall.  See how many seconds it takes for the primary winding to open and how much current it draws and how hot it gets....then you will know something.  Right now you are just knee jerking.  And what are the chances that any 50 watt transformer will ever have its secondaries completely shorted (not opened but shorted...think about it)......probably about the same as winning the lotto.   Really, never heard of it.

[toddbagwell]

Guys, please avoid personal attacks in the thread.

Thanks

[nc42acc]

Why modify something that sounds so good? I have all the items to mod Custard #1 but I am afraid it will make it worse.

[Phil A]

Why modify something that sounds so good? I have all the items to mod Custard #1 but I am afraid it will make it worse.

That's what audiophiles do - try to get that extra few percent of better sound (and that is usually a moving target).  Don't have the DAC (at least not yet) but have been following the thread with interest.

[HAL]

Custard DAC's and flaming transformers.  This is getting interesting!     

[PeteG]

Custard DAC's and flaming transformers.  This is getting interesting!     

LOL 

[nc42acc]

Phil once you try Custard you will never go back. Just do it, it's only $800!

That's what audiophiles do - try to get that extra few percent of better sound (and that is usually a moving target).  Don't have the DAC (at least not yet) but have been following the thread with interest.

[nc42acc]

What dish is that? Flaming Custard, sounds like bananas foster.

Custard DAC's and flaming transformers.  This is getting interesting!     

[Phil A]

There's nothing wrong with hot equipment, unless the police find you

[*Scotty*]

The problem comes inter-winding insulation failure on the primary side of the transformer. The voltage is higher and this increases the likelihood of a fault occurring. That being said the AC line fuse is there to prevent a fire from happening in the first place.
 So far no piece of electronics gear I have ever seen has been designed to be incombustible
and fireproof. When I have built electronics projects using toriodal transformers they have come with  neoprene mounting gaskets for the top and the bottom of the transformer. An upgrade would be a sorbothane gasket which you can cut out from sheets of sorbothane which can be ordered online from McMaster Carr in various thicknesses and Shore durometers. http://www.mcmaster.com/
Another mod would be to replace the steel mounting bolt with a brass bolt which is non-magnetic.
Scotty

[ACHiPo]

Why modify something that sounds so good? I have all the items to mod Custard #1 but I am afraid it will make it worse.

NC,
None of the changes made my X20 worse, but I don't think you're missing eargasmically mind blowing sound without them.  They are not even a cherry on top of the sundae, more like an extra sprinkle or 3.  I definitely don't think they're worth burning the house down, regardless of how low the probability is.

AC

[ACHiPo]

There's nothing wrong with hot equipment, unless the police find you

LMAO 

[nc42acc]

I am just being over dramatic and making excuses for not jumping in and modding Custard #1. Calling for rain tomorrow, might be the time to hit the workbench.

NC,
None of the changes made my X20 worse, but I don't think you're missing eargasmically mind blowing sound without them.  They are not even a cherry on top of the sundae, more like an extra sprinkle or 3.  I definitely don't think they're worth burning the house down, regardless of how low the probability is.

AC

[ACHiPo]

I am just being over dramatic and making excuses for not jumping in and modding Custard #1. Calling for rain tomorrow, might be the time to hit the workbench.

Well then, time to get busy!
 

[DaveC113]

I'd vote for keeping the fuse and upgrading to Audio Magic, Furutech, etc... The effects fuses can have range quite a bit though. I recently talked to a couple people who have tested a lot of fuses and AM and Furutech were the best in their opinion, but SR black was not involved which I've heard a lot of positive comments on. Neither liked SR red at all.

As far as mods, they usually make a small difference but are often overstated. What is one person's small almost unnoticeable change is another person's night-and-day change. It's all relative and in the ear/brain mechanism of the listener.

My guess would be that few could tell minor mods from bone stock in a blind test, but it's all in good fun and experiments are good. Too many people make up their mind without any experience and with incomplete or wrong information (and not just about audio). IMO it's best to keep an open mind.

[*Scotty*]

You could probably get a bigger improvement from swapping out opamgs in current to volt stage, assuming that it is not also a discrete circuit.
Scotty