[Edmund[_2_]]

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

[jamesgangnc]

"Edmund" wrote in message
...
May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few projects
now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

[Serge Auckland[_2_]]

"jamesgangnc" wrote in message
...
"Edmund" wrote in message
...
May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

I built a number of passive pre-amps using ALPS conductive-plastic pots.
Very quiet and smooth. As to switches, I used gold-plated toggle switches, a
bit of an inconvenience as you had to switch a source off as well as on, but
they were extremely reliable. The chip switches mentioned above will be good
provided the voltage levels are suitable and you have a power supply
available.

S
--
http://audiopages.googlepages.com

[Eeyore]

Edmund wrote:

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

What country / state / county do you live in ?

Graham

[Eeyore]

jamesgangnc wrote:

"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few projects
now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half reasomable like a
DG308 or 211. Or even discrete fets.

Graham

[Edmund[_2_]]

On Sat, 28 Jun 2008 17:59:22 +0100, Eeyore wrote:

Edmund wrote:

May be OT but I need an HQ pot meter for volume and a source selector
switch for my home build pre amplifier. For the selector switch, the
more selections the better! Can anyone point me in a good direction?

What country / state / county do you live in ?

Graham

Netherlands

Edmund

[jamesgangnc]

"Eeyore" wrote in message
...


jamesgangnc wrote:

"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects
now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half reasomable like
a
DG308 or 211. Or even discrete fets.

Graham

The spec sheet suggests they are ok. Did you test some?

[Eeyore]

jamesgangnc wrote:

"Eeyore" wrote
jamesgangnc wrote:
"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half reasomable like
a DG308 or 211. Or even discrete fets.

The spec sheet suggests they are ok. Did you test some?

4066s ? Sure. Look at the on resistance variation with applied signal level.
That means DISTORTION !

They are very inferior switches for audio. The Siliconix types I mentioned are
vastly better put purists use jfets.

I speak as a pro-audio designer btw.

Graham

[Serge Auckland[_2_]]

"Eeyore" wrote in message
...


jamesgangnc wrote:

"Eeyore" wrote
jamesgangnc wrote:
"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half reasomable
like
a DG308 or 211. Or even discrete fets.

The spec sheet suggests they are ok. Did you test some?

4066s ? Sure. Look at the on resistance variation with applied signal
level.
That means DISTORTION !

They are very inferior switches for audio. The Siliconix types I mentioned
are
vastly better put purists use jfets.

I speak as a pro-audio designer btw.

Graham


Yes, I missed the variation in on-resistance with voltage. My first design
job in Broadcast was to design audio routing switchers for OB vehicles. I
used a Siliconix jFET as a series element, and found that I didn't even need
a shunt element to provide more than acceptable isolation. However, with
professional levels, I couldn't get the switch to pass or stop +22dBu and
had to attenuate by 10dB going into the switch and restore by 10dB after.
Nevertheless, the router that resulted was considered at the time (1973)
pretty much state-of-the-art.

S.
--
http://audiopages.googlepages.com

[Eeyore]

Serge Auckland wrote:

"Eeyore" wrote
jamesgangnc wrote:
"Eeyore" wrote
jamesgangnc wrote:
"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half reasomable
like a DG308 or 211. Or even discrete fets.

The spec sheet suggests they are ok. Did you test some?

4066s ? Sure. Look at the on resistance variation with applied signal
level. That means DISTORTION !

They are very inferior switches for audio. The Siliconix types I mentioned
are
vastly better put purists use jfets.

I speak as a pro-audio designer btw.


Yes, I missed the variation in on-resistance with voltage. My first design
job in Broadcast was to design audio routing switchers for OB vehicles. I
used a Siliconix jFET as a series element, and found that I didn't even need
a shunt element to provide more than acceptable isolation. However, with
professional levels, I couldn't get the switch to pass or stop +22dBu

Doubtless insufficient pinch-offf voltage.


and had to attenuate by 10dB going into the switch and restore by 10dB after.
Nevertheless, the router that resulted was considered at the time (1973)
pretty much state-of-the-art.

To this day I still use the J109-112 and J172-5 or whatever discrete jfet
series.

Graham

[Serge Auckland[_2_]]

"Eeyore" wrote in message
...


Serge Auckland wrote:

"Eeyore" wrote
jamesgangnc wrote:
"Eeyore" wrote
jamesgangnc wrote:
"Edmund" wrote

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!
Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch
cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf

4066s are shockingly bad. At least consider something half
reasomable
like a DG308 or 211. Or even discrete fets.

The spec sheet suggests they are ok. Did you test some?

4066s ? Sure. Look at the on resistance variation with applied signal
level. That means DISTORTION !

They are very inferior switches for audio. The Siliconix types I
mentioned
are
vastly better put purists use jfets.

I speak as a pro-audio designer btw.


Yes, I missed the variation in on-resistance with voltage. My first
design
job in Broadcast was to design audio routing switchers for OB vehicles. I
used a Siliconix jFET as a series element, and found that I didn't even
need
a shunt element to provide more than acceptable isolation. However, with
professional levels, I couldn't get the switch to pass or stop +22dBu

Doubtless insufficient pinch-offf voltage.

That's right, but low-noise switching fets in 1973 were fairly new, and I
had to find one with sufficient pinch-off, yet with the smallest variation
in the on resistance with voltage. It was a trade-off, but it worked.


To this day I still use the J109-112 and J172-5 or whatever discrete jfet
series.

Graham

I'll remember those.
S.
--
http://audiopages.googlepages.com

[Edmund[_2_]]

On Sat, 28 Jun 2008 11:03:47 -0400, jamesgangnc wrote:

"Edmund" wrote in message
...
May be OT but I need an HQ pot meter for volume and a source selector
switch for my home build pre amplifier. For the selector switch, the
more selections the better! Can anyone point me in a good direction?

Thanks

Edmund

You might take a look at chip switches. I have used them for a few
projects now. You can use as many as you want. They switch cleaner.

http://focus.ti.com/lit/ds/symlink/cd4066b.pdf


Thanks for your suggestion but I don't want to use active
switches.

Edmund

[dizzy]

Edmund wrote:

May be OT but I need an HQ pot meter for volume and
a source selector switch for my home build pre amplifier.
For the selector switch, the more selections the better!

That's funny. I built a pre-amp a couple years back (based on a Doug
Self design), and it has exactly ONE input (CD). That's all I need it
for! 8)

However, I did provide the option of adding a switch and a second
input in the future... And a home-theater bypass!