Need help from fellow GraphTech Ghost users...

[shotgunn]

I've been installing GT's Ghost stuff for years. Something has come tony attention. I just installed the AcoustiPhonic system for a fellow forumite. We verified that everything worked, but didn't have time to do thorough testing. When my customer got home he tried it out on his rig with some of his presets. He noticed a white noise type hissing on high gain presets even with the volume is down. I then checked my own guitar that has this installed and show nuff... Turned down my gate and HISS city.

So, can I get some ghost users to try this out with no gate on. Also, I need to know how long you've had this installed so I can try to pinpoint when this has changed. The preamp from my guitar was actually just installed as a replacement to a defective unit I swapped out for an out of state customer.

Thanx,

shotgunn

[muudrock]

I have this system in my Lifeson LP. Is the preamp gain really cranked? When I first got it, had the same problem. I adjusted the preamp gain down via the little adjustment pot on the board and the hiss cleared up.

[boltrecords]

Thanks Shotgunn

I have this system in my Lifeson LP. Is the preamp gain really cranked? When I first got it, had the same problem. I adjusted the preamp gain down via the little adjustment pot on the board and the hiss cleared up.

Did the hiss clear up completely? Is there still more hiss on that guitar compared to a guitar without the ghost system? I'm noticing that my stock guitars have zero noise but the one with the ghost system have hiss/white noise.

[stevieray]

Any active preamp is gonna have a little self noise.

[shotgunn]

Any active preamp is gonna have a little self noise.

A little is fine... This is obscene.

[shotgunn]

I have this system in my Lifeson LP. Is the preamp gain really cranked? When I first got it, had the same problem. I adjusted the preamp gain down via the little adjustment pot on the board and the hiss cleared up.

Thanx for the response. The noise is from the magnetics and the piezos. The preamp gain only adjusts the level of the piezos. The magnetics are only buffered. Something is adding some nasty unbearable hiss.

[muudrock]

Thanks Shotgunn


Did the hiss clear up completely? Is there still more hiss on that guitar compared to a guitar without the ghost system? I'm noticing that my stock guitars have zero noise but the one with the ghost system have hiss/white noise.

It cleared up.....nearly...
When I have the amp gain up high I can still hear it, but it is negligible. I record with the guitar and cannot hear the hiss in the tracks.

There was a substantial difference after adjusting the preamp gain down. Might be how it's wired from Gibson compared to yours. I don't find it to be an issue now.

[MisterE]

The preamp adds hiss.
That's why I used the true bypass mod for mags.
When possible, I use the twin jack with true bypass on the mags.
DualJackMag

This clever circuit requires a second, Stereo Switched Jack. When you plug into this second jack, you've got your mags straight out (true bypass). Acoustic sound is available on the first jack. But with the second jack empty, the first jack has both mag and acoustic, in either Mono or Stereo mode -- in other words all the features of the Acousti-Phonic.

[Longhair]

Could you share the patches that are being used to get the hiss?

[simeon]

i installed the acoustiphonic system in my superstrat last year. i wired it up as per the instructions. i get hiss on the piezo side, but the mag side is silent. if i turn the piezo volume down, i get no hiss at all.

[shotgunn]

It cleared up.....nearly...
When I have the amp gain up high I can still hear it, but it is negligible. I record with the guitar and cannot hear the hiss in the tracks.

There was a substantial difference after adjusting the preamp gain down. Might be how it's wired from Gibson compared to yours. I don't find it to be an issue now.

For the magnetic wiring we went with two volume, master tone. The second tone was converted to piezo volume.

[shotgunn]

The preamp adds hiss.
That's why I used the true bypass mod for mags.
When possible, I use the twin jack with true bypass on the mags.
DualJackMag

This, I am aware of. However, my customer uses wireless and must be in mono. I may try TB'ing the mags and creating my own buffer/mixer to sum the two signals. I'll try this if I get a chance today.

[shotgunn]

Btw, before Morgan left GT he shared all of the GT diagrams with me. Some of the we came up with together for some my customers guitars that I was modding.

I actually just contacted him a few weeks ago.

[claxor]

Shotgunn,

I'm installing a graphtech acoustic system in a guitar with a Sustainaic system. Do you have a diagram for have these two systems work together?

[Diego]

No hiss at all here with the volume turned down

[shotgunn]

Shotgunn,

I'm installing a graphtech acoustic system in a guitar with a Sustainaic system. Do you have a diagram for have these two systems work together?

It won't let me upload it. PM me with your email address.

[boltrecords]

No hiss at all here with the volume turned down

Even with moderate gain with the gate off?

[claxor]

It won't let me upload it. PM me with your email address.

Sent.

[Longhair]

Is the Graph Tech Ghost QuickSwitch, #PE-0111-00 installed on the guitars that are hissing?

[shotgunn]

Is the Graph Tech Ghost QuickSwitch, #PE-0111-00 installed on the guitars that are hissing?

Yes.