Audiophile - plywood PCB ?

[kreed]

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.

The other pics on the bottom row show the same thing from other
angles.

That "pcb" looks like plywood to me. Does it improve the sound ?




The dual motor turntable a couple of rows up from there looks
interesting.
Why ?

 

[Tom]

On 27/01/2011 10:37 AM, kreed wrote:

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.

The other pics on the bottom row show the same thing from other
angles.

That "pcb" looks like plywood to me. Does it improve the sound ?

It's plywood but its not a PCB, probably the components are wired
underneath with wire. Haven't you seen pre-PCB electronics?

Tom

 

[Tom]

On 27/01/2011 10:50 AM, kreed wrote:
....

I realise that, hence the term "PCB" but why use it ?

My guess it is mostly visual effect, helps to extract money from fools.

Tom
>

 

[Phil Allison]

"kreed"

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.
The other pics on the bottom row show the same thing from other
angles.
That "pcb" looks like plywood to me. Does it improve the sound ?

** Gives it a better timbre I believe .....

But seriously, using plywood as the insulation material for a ( high
impedance) valve circuit is a very poor idea - cos wood is hydroscopic.

Once the wood absorbs even a small amount of moisture from the air - the
material will become conductive, resulting in serious bias shifts all over
the place and maybe producing cracking & squealing noises in the audio
output.

I have seen this actually happen when someone decided to rewire a modern
"Fender" guitar amp using a hard grey cardboard with solder studs and solid
wire in place of the original fibreglass PCB.
The problem proved near impossible to fix.

Original Fenders used a similar technique - but Fender had the sense to
fully impregnate their cardboard with hot wax beforehand.


..... Phil

 

[kreed]

On Jan 27, 10:47 am, Tom <t...@no.spam.invalid> wrote:

On 27/01/2011 10:37 AM, kreed wrote:



http://www.audiosalon.cz/gallery/id.87.html

Go to the bottom row of the gallery, then to the second pic from the
left.

The other pics on the bottom row show the same thing from other
angles.

That "pcb" looks like plywood to me.  Does it improve the sound ?

It's plywood but its not a PCB, probably the components are wired
underneath with wire. Haven't you seen pre-PCB electronics?

I realise that, hence the term "PCB" but why use it ?

Older gear I can remember was wired using tagstrips with components
wired point to point



> Tom

 

[Jasen Betts]

On 2011-01-27, kreed <kenreed1999@gmail.com> wrote:

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.

The other pics on the bottom row show the same thing from other
angles.

That "pcb" looks like plywood to me. Does it improve the sound ?

kind of like a matrix board, it's not printed on the back (so not a
_printed_ circuit board, just a support for the components), look how
the wires are terminated on rings of copper. dry cellulose is a good
insulator.

The dual motor turntable a couple of rows up from there looks
interesting.

I think that's got three motors, like the black one on the fifth row.

Why ?

run it off 3 phase power, less flutter

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[keithr]

On 27/01/2011 11:37 AM, kreed wrote:

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.

The other pics on the bottom row show the same thing from other
angles.

That "pcb" looks like plywood to me. Does it improve the sound ?

Definitely plywood, you can see the layers on the edge, but it looks
like discrete wiring not printed. Ok I suppose if it is dry and well
lacquered, the heat from the tubes should help keep it dry. There is a
guy in Canberra who makes expensive tube amps, he uses wooden strips
with brass screws as tag strips.

The dual motor turntable a couple of rows up from there looks
interesting.
Why ?

It probably uses high grade Burmese plywood needles

 

[Bruce Varley]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:ihqgb2$qf9$1@news-01.bur.connect.com.au...

"kreed"

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.
The other pics on the bottom row show the same thing from other
angles.
That "pcb" looks like plywood to me. Does it improve the sound ?


** Gives it a better timbre I believe .....

But seriously, using plywood as the insulation material for a ( high
impedance) valve circuit is a very poor idea - cos wood is hydroscopic.

Once the wood absorbs even a small amount of moisture from the air - the
material will become conductive, resulting in serious bias shifts all over
the place and maybe producing cracking & squealing noises in the audio
output.

I have seen this actually happen when someone decided to rewire a modern
"Fender" guitar amp using a hard grey cardboard with solder studs and
solid wire in place of the original fibreglass PCB.
The problem proved near impossible to fix.

Original Fenders used a similar technique - but Fender had the sense to
fully impregnate their cardboard with hot wax beforehand.


.... Phil

I was playing a gig with a band in a small town in the backwoods of Brazil,
the ancient valve PA amp blew up. Amazingly, the guys had a box of
miscellaneous bits in the back of the van, including unmarked diodes, caps,
some wire and basic electronic tools. Noone other than me had the slightest
clue about electronics, I offered to help but they said no, they'd handle
it. When they pulled the cover off there was mighty damage around the PSU
rectifiers, a big area of the board had carbonised and would certainly track
again if the only action was to replace the components.

The hacked away the damaged sections of the board, flattened a fag packet
and mounted bits and pieces from their parts box on it, shoving the wires
straight through the cardboard. Then they placed it next to the amp board
and wired it in. It looked like they didn't even check the direction of the
diodes. I've never held my breath harder than when they switched it on, but
it held together for the gig. 600+ volts to EL34s IIRC.

I bet other musos and roadies could come up with similar stories.

 

[Clifford Heath]

On 01/27/11 11:50, kreed wrote:

On Jan 27, 10:47 am, Tom<t...@no.spam.invalid> wrote:
On 27/01/2011 10:37 AM, kreed wrote:
It's plywood
I realise that, hence the term "PCB" but why use it ?

Plywood Circuit Board?

 

[Swanny]

On 27/01/2011 12:04 PM, Phil Allison wrote:

"kreed"

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.
The other pics on the bottom row show the same thing from other
angles.
That "pcb" looks like plywood to me. Does it improve the sound ?


** Gives it a better timbre I believe .....

But seriously, using plywood as the insulation material for a ( high
impedance) valve circuit is a very poor idea - cos wood is hydroscopic.

Once the wood absorbs even a small amount of moisture from the air - the
material will become conductive, resulting in serious bias shifts all over
the place and maybe producing cracking & squealing noises in the audio
output.

I have seen this actually happen when someone decided to rewire a modern
"Fender" guitar amp using a hard grey cardboard with solder studs and solid
wire in place of the original fibreglass PCB.
The problem proved near impossible to fix.

Original Fenders used a similar technique - but Fender had the sense to
fully impregnate their cardboard with hot wax beforehand.


.... Phil

Couldn't get the Protel router to work on plywood so I used the Makita
instead.

 

[no one]

wood nt every one want one of these ?? he he he


"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:ihqgb2$qf9$1@news-01.bur.connect.com.au...

"kreed"

http://www.audiosalon.cz/gallery/id.87.html


Go to the bottom row of the gallery, then to the second pic from the
left.
The other pics on the bottom row show the same thing from other
angles.
That "pcb" looks like plywood to me. Does it improve the sound ?


** Gives it a better timbre I believe .....

But seriously, using plywood as the insulation material for a ( high
impedance) valve circuit is a very poor idea - cos wood is hydroscopic.

Once the wood absorbs even a small amount of moisture from the air - the
material will become conductive, resulting in serious bias shifts all over
the place and maybe producing cracking & squealing noises in the audio
output.

I have seen this actually happen when someone decided to rewire a modern
"Fender" guitar amp using a hard grey cardboard with solder studs and
solid wire in place of the original fibreglass PCB.
The problem proved near impossible to fix.

Original Fenders used a similar technique - but Fender had the sense to
fully impregnate their cardboard with hot wax beforehand.


.... Phil