PRS 408 pickup output

[BlueSky]

I have a PRS 408 which sounds rather lifeless. The pickups produce a sound but there are no harmonics and no note bloom. I tried to measure the output of the pickups with a voltmeter and there's nothing. My other humbucker guitars have the usual output of 8-9k but the 408 produce nothing. Could there be a problem with the wiring? Very strange that I cannot measure the output of the pickups.

 

[munyonm]

That is concerning. My 509 had a problem with the neck pickup in humbucker mode where it was measuring in the range of ~400k and had super low output, but that was a back pickup that was replaced at the PTC under warranty.

Is this a recent discovery? It’s possible that it is the wiring, if the resistance is 0Ω, then you have a ‘dead short.’ Are you comfortable opening up the control cavity and doing some further investigation? It should be pretty easy to get a schematic for the guitar from the PRS site in the support area.

It‘s also worth checking your multi-meter settings to ensure that it wasn’t trying to take a different measurement (like current or voltage) or if it was in ‘auto-range’ or was set to milli-ohms resistance or something like that.

 

[BlueSky]

Thanks for responding. Really appreciate that.
I‘ve had the guitar for several years but never played it because it‘s so lifeless. I always thought it‘s because it has a rosewood neck.
It‘s only recently when I thought of measuring the pickups and the resistance is 0Ω. The voltmeter ist set correctly because when I grab another guitar they measure the usual 8-9k.
It‘s 0Ω on both pickups, so I hope the wiring is faulty and not the pickups. They do make a sound and the splitting seems to work, but it simply sounds lifeless. I‘m the first owner and bought it new.
I found the 408 wiring diagram. I will take the guitar to a luthier/tech this week.

 

[munyonm]

I hope it is just some excess solder or something simple that is just shunting your signal to ground.

Please post up when the solution is found. I am curious to hear what was wrong.

 

[BlueSky]

I‘ll take the guitar to a tech next week. I‘ll certainly let you know what the problem is.

 

[Broseph]

I would check the cavity. Make sure nothing is causing something to go to ground. Compare your schematic to the PRS one to make sure.
https://d159anurvk4929.cloudfront.net/documents/408_2017.pdf

 

[László]

The 408 pickups aren't lifeless. Sounds like there's something wrong.

 

[BlueSky]

I would check the cavity. Make sure nothing is causing something to go to ground. Compare your schematic to the PRS one to make sure.
https://d159anurvk4929.cloudfront.net/documents/408_2017.pdf

Will do, and take it to a tech to check for cold solder joints.

 

[BlueSky]

The 408 pickups aren't lifeless. Sounds like there's something wrong.

I've had this guitar for nine years and never played it because it just doesn't sound good. Lifeless is the best term to describe it. Unplugged it sounds great but when I plug it in the pickups work but there are no harmonics, no note bloom, no feedback. Just, well, lifeless. All those years I thought it's because of the rosewood neck -- until I thought 'let's measure the pickup output'. Well, I'll find out next week.

 

[BlueSky]

I've just checked the cavity and compared it to the 408 wiring diagram. There are some deviations. For example, in addition to the treble bleed cap and the tone cap, there is a big fat yellow capacitor between the volume pot and the pickup switch. That is not on the diagram. Does anybody know about this? I could post some pics but apparently that does not work via attachment.

 

[László]

I've just checked the cavity and compared it to the 408 wiring diagram. There are some deviations. For example, in addition to the treble bleed cap and the tone cap, there is a big fat yellow capacitor between the volume pot and the pickup switch. That is not on the diagram. Does anybody know about this? I could post some pics but apparently that does not work via attachment.

I've not heard of that. Interesting.

PRS' published specs for the 408 are Treble 9.7k. and Bass 9k. Other than the Tremonti, these are among the highest DC resistance specs of all PRS pickups.

You can find the PRS charts in this thread:

PRS Pickups Output: Collaborative Database

I thought some of us PRS owners here might want to construct a collaborative database of the output of various PRS pickups, as you measure them in your guitars. The readings are sometimes pretty interesting when it comes to discussions of "How hot are the XYZ pickups, anyway?" First off, a...

forums.prsguitars.com

The pickups on mine (I've owned 3, one of my current guitars is a PS with them) have all been hot enough that I generally run the 408 volume at around 6-7 and turn down the tone control a little, too, unless I'm looking for a lot of gain.

 

[BlueSky]

There‘s definitely something wrong with mine. I wish I could post the gut shots I made earlier.

 

[Max Headroom]

There‘s definitely something wrong with mine. I wish I could post the gut shots I made earlier.

This might help you out

how to post pics?

see above!

forums.prsguitars.com

 

[BlueSky]

This might help you out

how to post pics?

see above!

forums.prsguitars.com

Thanks, but I don‘t have photobucket or anything like that.

 

[munyonm]

I don’t mind hosting some of those photos for you. I already pay for SmugMug to back up personal photos, so it won’t cost me anything to host them for you. Especially if it gets you on the path to enjoying that guitar.

 

[Max Headroom]

Yeah, me neither but another member told me about this service which is free and I now use it all the time.
Thanks @DISTORT6 !

Postimages — free image hosting / image upload

Provides free image upload and hosting integration for forums. Free picture hosting and photo sharing for websites and blogs.

postimages.org

 

[BlueSky]

I don’t mind hosting some of those photos for you. I already pay for SmugMug to back up personal photos, so it won’t cost me anything to host them for you. Especially if it gets you on the path to enjoying that guitar.

Thanks, that's very kind of you. I sent the pics a moment ago.

 

[László]

There‘s definitely something wrong with mine. I wish I could post the gut shots I made earlier.

It occurs to me that if you bought it new, it might be covered under the PRS lifetime warranty.

If not, maybe someone modded it incorrectly?

 

[Glide-bpm]

Yeah, my 408 and ones that I've owned have been awesome and anything but lifeless! Agree on a possible dead short.

 

[munyonm]

@BlueSky, here are those pictures: