Why sound diferents?

[tadiam]

In the last month build 3 prototypes similar to rod p3a and my question is..why in similar amps schemas this amps sound diferents?
what components in an amplifier have greater influence in the sound?
I use the same transistors,resistors,caps....
In the next post put the schemas
Tadiam

[sakis]

pcb makes a change
ground rooting makes a change
ltp transistors make a change
vas transistor makes a change
decoupling caps makes a change .
input capacitor makes a change
OUTPUT TRANSISTORS MAKE A HELL OF A CHANGE....

may be others will scream with the next paragraph .....

but i can tell you that all the above make audible diference

keep trying .... one of them you will like the best .... so stay with it ....

this is what i did ....

[tadiam]

ok
and add in your large list the caps value in the power supply (in my case more value more bass)and less treble?
in my other experimen build two identical pc boards..in the first used small metel film resistors and the second normar carbon resistors..what happen?(the rest components are the same)
First..metal film resistors more clear an clinical delimited sound but metelic and fatigue "sound"to my ears
two.. normal carbon resistors more muted sound but soft and pleasant sound.

NFB resistors too have influence.
boad size.
boards? glass fiber or pertinax
some diodes
regulators
drivers transistors


add too a your list the amp case...my amps generally sound best when this have on the table
put this in an metalic case and the sound turn flat and no clinical?

the search continue

[sakis]

driven to a chaos like this .....

ithing first you have to construct with some rules .....

meaning try to construct in a specific board ( keep the rules )
a specific list of material
a specific box and then try to improove after some practice is allready made....

i ha d do design a P3 board to fit in specific size 22 cm long and 3 cm wide well it worked but didnt sound nice ( ground rooting ) rules .....

give us some pictures

[nelsonvandal]

This is a novice experience:

Coming from the Head-Fi world, listening to phones, I can tell the quality of the current return route is equally important to the amplifier itself. Many good headphone amps use an active ground channel sinking current. The output impedance of this ground channel has to be very low, otherwise you get a thin, overly spacious and hollow sound. Changing the ground channel amp alters the sound just as much as changing the L/R amps. If you have a passive ground, I guess the quality and size of the caps sinking current is of equal importance.

I think active components color the sound more than passive. Every transistor has it's own sound.

I think there's a JFET and a bipolar sound. I have no experience from MOSFETs.

Do a PCB really make an audible difference? Using exactly the same components and ground route, can you hear the PCB? Can you describe what you've heard?

[sakis]

but from other material i dont know ...i also cannot imagine .....

but for shure diferent size and componet routing ,distance between eachother ,proximity and so on make for shure audible diference ....

i presume proximity between traces formates capacitance that effects sound ....but how much and why i cannot really tell ......

2 exactly same schematics ......exactly same componets...one single layer ...the other double layer and there fore smaller ...sounded totally diferent ....but why i cannot tell ....