My humble comment on HuangYong's DIY amp

[julery 0]

i am using jr455.just to clarify.

Hmmm, is that a better op-amp then Grado's one, why dun use 4556 as you had mentioned earlier it's grado's replica?

Edited October 7, 2003 by julery

[huangyong 0]

sorry , typo error, it is jr4556.... got it from rameish. there's no such thing as 455.....sori...

[julery 0]

sorry , typo error, it is jr4556.... got it from rameish. there's no such thing as 455.....sori...

icic...it's ok bro .

[fishball79 0]

I personally think, if it doesn't follow the circuitry, using the same parts throughout its hardly even a copy. To deviate from the circuitry means its not a copy at all.

 

In fact one can be anal and say a clone has to have everything the same, potting of circuitry and mahogany box included...

 

I think the best bet is to hear real one and the copy/clone/alternative side by side

 

[Rameish 0]

i dun like the warm sound so i change the opamp and bring it to mychew, may be this is the reason.

 

AC adapter is 12V 500mA, enough power?? not sure.

Btw, i will try it out will a stand alone regulated power supply and see how.....

 

and the power cap, i use electrolytic caps in parallel with ploy cap.

to try out new things.

 

 

 

still waiting for opinion from you all.

Huh...so somewhere you did switch the op-amp back to 4556? But you glued the box! I'm totally confused. Also you mentioned a generic poly and elect caps - these are not in a Grado RA-1.

 

Anyway, if you and the owner were happy about it that would be one thing but it seems you both are/were not.

 

Why all the cloak & dagger? We're used to messy wires.

[julery 0]

i dun like the warm sound so i change the opamp and bring it to mychew, may be this is the reason.

 

AC adapter is 12V 500mA, enough power?? not sure.

Btw, i will try it out will a stand alone regulated power supply and see how.....

 

and the power cap, i use electrolytic caps in parallel with ploy cap.

to try out new things.

 

 

 

still waiting for opinion from you all.

Huh...so somewhere you did switch the op-amp back to 4556? But you glued the box! I'm totally confused. Also you mentioned a generic poly and elect caps - these are not in a Grado RA-1.

 

Anyway, if you and the owner were happy about it that would be one thing but it seems you both are/were not.

 

Why all the cloak & dagger? We're used to messy wires.

I might like the warmer sound

Edited October 8, 2003 by julery

[huangyong 0]

julery, you like warm sound?????

ok, will figure out some mod after exam, then can fix the prob for you..

[Mackie 0]

For what it's worth, sonic traits do not exhibit itself in the amp alone, the entire link from source to cans have to be considered. Food for thought perhaps?

Edited October 10, 2003 by Mackie

[Rameish 0]

I suggest you bring the amp back to Grado RA-1 specs. That is remove the electro caps and put in 5.1uf 400 volt Solens and put the 4556 op-amp in an ic socket so he can op-amp roll a few other types. From there, think about synergy with other components in the chain including the IC.

[julery 0]

julery, you like warm sound?????

ok, will figure out some mod after exam, then can fix the prob for you..

No hurry , take your time.

[huangyong 0]

Rameish,

sorry for confusing you. i am here to clarify all the parts that i used.

 

Resistors: metal film

Signal cap: Solen 5.1uF

Power rail cap: Electro cap(100uF) parallel with poly cap(0.47uF) parallel with ceramic cap (470pF).

 

[Rameish 0]

I can understand using the electro cap (to reduce the "pop" sound ) when switching the amp on/off, but why the need for the poly cap? The 2 main items that contribute to the sound of the RA-1 are the op-amp and the Solens. The ceramic cap is for stability.