[fishski13]

for a 2-board passive ground, do i still need to connect RCA ground to chassis, or isolate? as you can see from the pic, i have no RCAs. instead i have one wire for each signal ground (the green wires in the pic) soldered into the pot input ground tabs to connect to the chassis for a 3-board active ground.

 

[n_maher]

I hope you have some strain relief on those wires.

 

[amb]

fishski13, as long as your amp's signal ground is tied to the chassis then it's fine.

 

[fishski13]

Quote:

Originally Posted by n_maher /img/forum/go_quote.gif I hope you have some strain relief on those wires.

it's bomber.

 

[Possede]

I've noticed that some people are using a filtered power entry plug, like this one. What are the benefits of using an expensive power entry plug compared to the generic, cheap ones. Do the benefits justify the price?

 

[Beefy]

I use the Schaffner FN282 or FN284 IEC inlets.

I really can't say whether they 'perform' better...... but for me the benefits of the extra cost included the double fusing and double-pole switching for safety, and the fact that they are all-in-one units for a cleaner panel.

 

[fishski13]

Beefy,
your avatars always freak me out. thanks, i just had to get that off my chest

.

chassis wiring is done, although i think i may re-do the PS hook-up wiring to the amp boards. i guess i don't know how important it is to twist the wiring once it's inside the chassis. my unbillical from the sigma22 is shielded 16 awg. i have to spend some time ohming everything out as well before the first power up tomorrow night - wish me luck!!! the sigma22 is tested and working. this build has been too easy up to this point - i hope my luck continues.

PACE

 

[DouglasQuaid]

Quote:

Originally Posted by Possédé /img/forum/go_quote.gif I've noticed that some people are using a filtered power entry plug, like this one. What are the benefits of using an expensive power entry plug compared to the generic, cheap ones. Do the benefits justify the price?

Some DIYers back in the day swore off the use of filters on the IEC input. Said it killed dynamics. I like to agree and trust a well-designed power supply to take care of noise as opposed to some ridiculously cheap inductor network.

 

[Beefy]

Quote:

Originally Posted by DouglasQuaid /img/forum/go_quote.gif Some DIYers back in the day swore off the use of filters on the IEC input. Said it killed dynamics.

Please explain how, in established electronic engineering terms. Thanks.

Quote:

I like to agree and......

Which is often the problem.

Quote:

well-designed power supply to take care of noise as opposed to some ridiculously cheap inductor network.

And there is something specifically wrong with using both?

 

[linuxworks]

Quote:

Originally Posted by DouglasQuaid /img/forum/go_quote.gif Some DIYers back in the day swore off the use of filters on the IEC input. Said it killed dynamics.

no such thing as 'dynamics' in power supplies! lol.

this is not any kind of explanation. its not even possible. sorry.

 

[linuxworks]

Quote:

Originally Posted by Possédé /img/forum/go_quote.gif I've noticed that some people are using a filtered power entry plug, like this one. What are the benefits of using an expensive power entry plug compared to the generic, cheap ones. Do the benefits justify the price?

I get my iec filters at a local surplus store. they're cheap and so I use them.

they stop high frequency stuff from getting in; but also people tend to forget that they stop stuff from getting out (if your box is digital, it might dump 'stuff' on the power rails and if you have an iec filter that can suppress some of that getting back into the common ac power line).

 

[DouglasQuaid]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Please explain how, in established electronic engineering terms. Thanks. And there is something specifically wrong with using both?

You want me to define hearsay? Okay.

"evidence based not on a witness's personal knowledge but on another's statement"

If you don't notice a difference, go ahead and use one.

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif no such thing as 'dynamics' in power supplies!

Do you honestly believe power supply quality has no bearing on the dynamics of an amplifier? I suppose you also believe people build discrete power supplies for their amps just because they look cool.

 

[luvdunhill]

Quote:

Originally Posted by DouglasQuaid /img/forum/go_quote.gif You want me to define hearsay? Okay. "evidence based not on a witness's personal knowledge but on another's statement"

so, wait, you've tried both then? what was your conclusion? what other variables changed?

 

[m1abrams]

Quote:

Originally Posted by DouglasQuaid /img/forum/go_quote.gif Do you honestly believe power supply quality has no bearing on the dynamics of an amplifier? I suppose you also believe people build discrete power supplies for their amps just because they look cool.

That is not what he said. A DC power supply should have no dynamics to it. The idea is to be constant. I too am confused how "dynamics" can be removed by filtering the AC going into a DC power supply.

A good DC PS does one thing provide the most constant ripple free DC Voltage (if it is a constant Voltage source) that it can over various current loads. So it should not have dynamics.

 

[linuxworks]

Quote:

Originally Posted by DouglasQuaid /img/forum/go_quote.gif Do you honestly believe power supply quality has no bearing on the dynamics of an amplifier? I suppose you also believe people build discrete power supplies for their amps just because they look cool.

a lot of the time, people build discrete FOR the 'oooh, aaaah!' factor. truly. its irrational but a lot of builders and buyers are. truth!

the power supply keeps the caps charged and those supply power to the circuit. I'm still not seeing where 'dynamics' enter into it.

even worse, I'm not seeing - AT ALL - where filter L and C elements at the power line (before the trafo) will hurt a single thing. please give some tech reason for why you feel this rfi filter hampers anything.