Marshall Amp Forum - View Single Post - WTB: Marshall JMP-1 Preamp

Kendall124 · 07-01-2008, 02:54 AM

Well, here's the thing. My ears are wasted. Yep, 20+ years of having 100 watt amps behind me have taken there toll. Now don't get me wrong, I still hear just fine but as to being able to pick out all of the slight variations in frequency? Nope. All I can tell you is before I shipped her to VooDoo it was really brittle sounding. I had purchased (2) EH12ax7's. I didn’t notice much difference. It came back from VooDoo with an EH12ax7 and a Groove Tube 12ax7 gold pin in her. I should have opened it up to see if I could tell what they did. They're kinda secretive about what it is they really do. Truthfully, I thought all they did was change the tubes because it was still really noisy when she came back. The guys at VooDoo told me to keep the patches volumes to no more than 15. Then keep the output knob at 9 o'clock. Anything above that brings on the noise. My clean tone is incredible. Beautiful bell tones. I'll share some of my settings with ya once yours arrives. Actually, I have a spreadsheet of EVEYONES patches that I could find on the internet. Some are great some are... um... some are ok. It all depends on the amp you're sending it through. I'm also finding out that volume has a lot to do with the tone. As with all Marshall's, she gets better the more you push her.
So that’s my two cents on VooDoo. It definitely came back a better, more controllable preamp. Would I recommend the mod? Yes.
K

07-01-2008, 02:54 AM	#6 (permalink)
Kendall124 Senior Member Join Date: Apr 2008 Location: Seattle WA Posts: 109	Re: WTB: Marshall JMP-1 Preamp Well, here's the thing. My ears are wasted. Yep, 20+ years of having 100 watt amps behind me have taken there toll. Now don't get me wrong, I still hear just fine but as to being able to pick out all of the slight variations in frequency? Nope. All I can tell you is before I shipped her to VooDoo it was really brittle sounding. I had purchased (2) EH12ax7's. I didn’t notice much difference. It came back from VooDoo with an EH12ax7 and a Groove Tube 12ax7 gold pin in her. I should have opened it up to see if I could tell what they did. They're kinda secretive about what it is they really do. Truthfully, I thought all they did was change the tubes because it was still really noisy when she came back. The guys at VooDoo told me to keep the patches volumes to no more than 15. Then keep the output knob at 9 o'clock. Anything above that brings on the noise. My clean tone is incredible. Beautiful bell tones. I'll share some of my settings with ya once yours arrives. Actually, I have a spreadsheet of EVEYONES patches that I could find on the internet. Some are great some are... um... some are ok. It all depends on the amp you're sending it through. I'm also finding out that volume has a lot to do with the tone. As with all Marshall's, she gets better the more you push her. So that’s my two cents on VooDoo. It definitely came back a better, more controllable preamp. Would I recommend the mod? Yes. K __________________ Make a joyful noise unto the Lord.