Adequate switch for UL-triode-pentode

mskl99 · 17th February 2013, 08:42 AM

I would like one 4P3T switch or 2 2P3T switches to switch between UL-triode-pentode mode for a quad of EL34's.
Do I need a switch rated for hundred of volts DC. I see a lot of switches rated for, say, 250V AC and multiple amps of current. Are those OK. Also, do I need a super high quality switch.
Any specific suggestions would be greatly appreciated.
Thanks,
Mike

azazello · 17th February 2013, 10:28 AM

Quad per channel, or two pair for stereo?

mskl99 · 17th February 2013, 10:37 AM

2 pairs for stereo, both pairs in the same chassis.
Mike

azazello · 17th February 2013, 11:07 AM

250 v/1 or 2 A. Small chinese micro switches are not suitable /with small contacts inside/.

Merlinb · 17th February 2013, 02:05 PM

In theory you should get a switch with a peak voltage rating that exceeds the amp's DC supply voltage (since the voltage between some of the contacts may swing that much), but a heavy-duty 240V switch should be fine in practice.

mskl99 · 17th February 2013, 02:42 PM

Is that 240V AC? The DC ratings of most of the switches I have seen are considerably lower than their AC ratings.

Merlinb · 17th February 2013, 07:03 PM

Quote:

Originally Posted by mskl99

Is that 240V AC? The DC ratings of most of the switches I have seen are considerably lower than their AC ratings.

Yes AC. Since you will presumably only switch it when the amp is off, it's DC break capability isn't really an issue. The DC current screen current is quite small in any case.

mskl99 · 18th February 2013, 03:50 AM

Thanks, everybody, for your help. This is one of those little newbie issues that can take more research than the actual amplifier design.

17th February 2013, 08:42 AM	#1
mskl99 diyAudio Member Join Date: Jul 2011	Adequate switch for UL-triode-pentode I would like one 4P3T switch or 2 2P3T switches to switch between UL-triode-pentode mode for a quad of EL34's. Do I need a switch rated for hundred of volts DC. I see a lot of switches rated for, say, 250V AC and multiple amps of current. Are those OK. Also, do I need a super high quality switch. Any specific suggestions would be greatly appreciated. Thanks, Mike

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17th February 2013, 10:28 AM	#2
azazello diyAudio Member Join Date: Aug 2008 Location: Bulgaria	Quad per channel, or two pair for stereo?

17th February 2013, 10:37 AM	#3
mskl99 diyAudio Member Join Date: Jul 2011	2 pairs for stereo, both pairs in the same chassis. Mike

17th February 2013, 11:07 AM	#4
azazello diyAudio Member Join Date: Aug 2008 Location: Bulgaria	250 v/1 or 2 A. Small chinese micro switches are not suitable /with small contacts inside/.

17th February 2013, 02:05 PM	#5
Merlinb diyAudio Member Join Date: May 2006 Location: York	In theory you should get a switch with a peak voltage rating that exceeds the amp's DC supply voltage (since the voltage between some of the contacts may swing that much), but a heavy-duty 240V switch should be fine in practice.

17th February 2013, 02:42 PM	#6
mskl99 diyAudio Member Join Date: Jul 2011	Is that 240V AC? The DC ratings of most of the switches I have seen are considerably lower than their AC ratings.

18th February 2013, 03:50 AM	#8
mskl99 diyAudio Member Join Date: Jul 2011	Thanks, everybody, for your help. This is one of those little newbie issues that can take more research than the actual amplifier design.