| Author | Message | ||
| squirefan01
Junior Username: squirefan01 Post Number: 28 Registered: 6-2007 |
Hey all, I wrote way back in late 2009 about this, and just saw today that Mica had responded. I have a '99 Essence with Europa electronics. The treble toggle switch pops loudly the first time I move it after plugging in. In this archived thread: http://alembic.com/club/messages/394/71672.html Mica asked if a 1 Meg resistor was present . I just looked and see that the one she points to is not. In fact, in the pictures she showed there were 4 blue resistors but in my electronics there are only 2. In my setup, the resistor down between the switches is brown. If you want to look up info on this bass, the serial number is 99K12239. How can I get this updated? Can I get a schematic that shows the latest layout of all Europa electronics? Thanks! | ||
| squirefan01
Junior Username: squirefan01 Post Number: 29 Registered: 6-2007 |
Bump. Just checking in  | ||
| squirefan01
Junior Username: squirefan01 Post Number: 30 Registered: 6-2007 |
Still wondering about how to update the electronics to get rid of this pop. Thanks! | ||
| dfung60
Senior Member Username: dfung60 Post Number: 483 Registered: 5-2002 |
I'm sure you'll get the definitive description from Mica, but the fix is pretty simple. All you need is a 1MegOhm resistor. You can get this at any electronics store (even Radio Shack) for a buck for multiple pieces. The ones in the picture are high quality resistors (1Meg, 1% tolerance) which will be harder to buy casually, but I don't think it will matter (try to get a 5% if you can and avoid the 20% tolerance). Unlike this other resistors in the picture, this one is in parallel with the red capacitor - the two leads of the resistor are connected to the two leads of the capacitor. In the picture, the leads of the resistor are not insulated - I think you want to make sure that they ARE insulated, as you'll have problems if those bare leads come into contact with the (conductive painted) control cavity or anything else in there. The reason the one big pop happens is that when the circuit is switched to have the capacitor in the circuit it gets charged up and can hold the charge when you switch it out of the circuit, even when the instrument is unplugged. When you plug in next time, the first time you flip the treble switch, the cap discharges it's stored current which you hear as a pop. Adding the resistor across the capacitor causes it to drain when it's sitting in your case, which should eliminate the pop. You need a big value resistor so it doesn't affect the tone control, but the precise value isn't a big deal. The resistors in the picture are super-high quality parts and they're often light blue instead of brown. But the color of the parts doesn't matter, just the value. For the other resistors in this network, they're setting the frequencies of the controls, so they need to be exact, but this resistor across the cap doesn't matter. Hope this helps, David Fung | ||
| squirefan01
Junior Username: squirefan01 Post Number: 31 Registered: 6-2007 |
Thanks David! This info sheds some light on what needs to be done. I thought I might need to also replace other resistors that looked different than mine as well, so it's great I just need to replace this one. I am on the hunt for it now. Also good to get an explanation to verify that this will only happen once per session and I don't have to worry about it happening in the middle of a set (as long as I just flip the switch as soon as I plug in to release the energy)! Thanks again, Greg | ||
| dfung60
Senior Member Username: dfung60 Post Number: 485 Registered: 5-2002 |
Greg - After you add the resistor I don't think you'll hear the problem again. But if you don't add it, I think the problem could happen at any time. If you're playing and flip the switch, it might not be as noticeable as when you're first setting up and it's quiet. Alembic sometimes has a "it's too good" problem. I think the garden variety ceramic cap is too leaky to have this problem, but the expensive one that Alembic uses is quite happy to hold the charge for a good long time. David Fung | ||
| mica
Moderator Username: mica Post Number: 7282 Registered: 6-2000 |
Those brown resistors are Allen Bradley hot molded ones and we'd use them still if they hadn't shut down the factory in Michigan. Just add the ones shown in the pic, that's how we still do it. | ||
| squirefan01
Junior Username: squirefan01 Post Number: 32 Registered: 6-2007 |
I finally added the resistor you pointed to in the photos and all is well now. So much better now! Thanks for the help! |
