Hi all.
Just picked up a Audio Design 10a amp and matching Model 1 pre amp (Made in Canada Eh!)and was looking to do some updates to it.
Checked DC offset and ran it on some test speakers before using it on my good speakers.
This is one powerful little amp! Rated at 100 watts a channel, but drove my Thiel CS3.6 speakers no problem at all, and they are not easy to drive.
Didn't even hardly get warm playing at pretty good levels.
Updates I would like to do:
1. No power switch from the factory, would like to add one.
2. Captive old school 14 ga brown lamp cord, going to add a IEC connector and use my decent aftermarket AC cords.
Kinda new to playing with internal wiring so I want to be sure of what I am doing.
I have the tools to cut into the case for the IEC connector, and I was considering using a round power switch in the hole where the current AC cord runs into the chassis.
I guess the main question is, do I just wire the switch in the hot (white) wire in series as long as the switch is rated for 125v 15amp?
I do not think I can switch the transformer on and off, or if that is ever done?
I am guessing most circuits switch the hot lead?
Opinions?
The pre amp is another story, someone switched the transformer, and the power switch does not turn the pre on or off, no big deal, pre amp can be left on, but I may look into getting that sorted out, and with the volume all the way down, music still plays, but real low, so something is amiss there.
Dave.
Just picked up a Audio Design 10a amp and matching Model 1 pre amp (Made in Canada Eh!)and was looking to do some updates to it.
Checked DC offset and ran it on some test speakers before using it on my good speakers.
This is one powerful little amp! Rated at 100 watts a channel, but drove my Thiel CS3.6 speakers no problem at all, and they are not easy to drive.
Didn't even hardly get warm playing at pretty good levels.
Updates I would like to do:
1. No power switch from the factory, would like to add one.
2. Captive old school 14 ga brown lamp cord, going to add a IEC connector and use my decent aftermarket AC cords.
Kinda new to playing with internal wiring so I want to be sure of what I am doing.
I have the tools to cut into the case for the IEC connector, and I was considering using a round power switch in the hole where the current AC cord runs into the chassis.
I guess the main question is, do I just wire the switch in the hot (white) wire in series as long as the switch is rated for 125v 15amp?
I do not think I can switch the transformer on and off, or if that is ever done?
I am guessing most circuits switch the hot lead?
Opinions?
The pre amp is another story, someone switched the transformer, and the power switch does not turn the pre on or off, no big deal, pre amp can be left on, but I may look into getting that sorted out, and with the volume all the way down, music still plays, but real low, so something is amiss there.
Dave.
Attachments
In the US black is hot. I believe that's true in Canada also. The line cord normally goes to the transformer primary
through a fuse in the hot lead. Sometimes both the hot and neutral are fused.
Sound can be heard with the volume at minimum due to unshorted resistance in the element,
or actual resistors between the pot and ground, to reduce hum.
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Hi.
You are correct, white is neutral, duh!
Bit of a brain fart.
The amp has a fuse in the one lead, so switch it before the fuse or after?
I am a mechanic by trade, and deal with dc more than ac, but I guess power is power.
When I do the IEC connector, the amp currently does not have a ground wire, only a two prong cord, should I just leave it like that, or ground the center pin?
Just wondering if I do ground it, I may get hum, and it is dead quite now, not even any transformer buzz, even with the old school transformer.
Thanks for the input.
Dave.
You are correct, white is neutral, duh!
Bit of a brain fart.
The amp has a fuse in the one lead, so switch it before the fuse or after?
I am a mechanic by trade, and deal with dc more than ac, but I guess power is power.
When I do the IEC connector, the amp currently does not have a ground wire, only a two prong cord, should I just leave it like that, or ground the center pin?
Just wondering if I do ground it, I may get hum, and it is dead quite now, not even any transformer buzz, even with the old school transformer.
Thanks for the input.
Dave.
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The fuse should always be connected immediately to the hot conductor after it enters the chassis.
Also, the chassis should always be grounded directly to the IEC ground pin for safety.
However, if you do get significant hum from this connection, there are certain measures
that you can take elsewhere in the circuit to minimize the hum. Do you have the amplifier schematic?
Please be very careful working on this.
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That is going to be the hard part, that is why I was going to search for a round power switch that I can re-use the hole in the chassis where the current AC cord is.
Have not spent any time looking for switches yet, I am pretty sure selection is limited in Canada, but I do have a full blown electronics store that seems to have everything not far from where I work, probably worth a trip over to see them.
Dave.
Have not spent any time looking for switches yet, I am pretty sure selection is limited in Canada, but I do have a full blown electronics store that seems to have everything not far from where I work, probably worth a trip over to see them.
Dave.
Try something like this:
R13112AAAA | Black SPST Rocker Switch, On-Off, 16 A@ 250 V ac 20.2mm | Arcolectric
Sajti
R13112AAAA | Black SPST Rocker Switch, On-Off, 16 A@ 250 V ac 20.2mm | Arcolectric
Sajti
I had the same problem. Just measure the resistance between pot left pins (looking from shaft end) and center pin (wiper). If its more than zero when pot is in fully CCW position, that is the problem and you can replace the pot (in my case, I switched to a stepped pot and the problem vanished).
Thanks for the tip Prasi!
Do you happen to remember what pot you used? Brand and model?
If I need to change it, I was thinking of an Alps pot.
Anyone want to chime in on what pot to use and best place for a Canadian to purchase said pot?
Thanks again.
David
Do you happen to remember what pot you used? Brand and model?
If I need to change it, I was thinking of an Alps pot.
Anyone want to chime in on what pot to use and best place for a Canadian to purchase said pot?
Thanks again.
David
It was a decent quality pot but made with SMD 1% MFR's and make before break contact. I also found that its channel balance (left and right channel resistances) are equal at all volume settings. Here is the link. 21 Step High Precision Step Potentiometer A50KX2
you may be able to get similar one from the ebay or other online vendors locally.
regards
Prasi