converting a silver face vibrolux to a blackface

hmx1 · February 7th, 2006, 08:45 PM

Hi Guy's,
I appreaciate all the answers to my vibrolux questions and now I have more... LOL
I have a friend who is a retired TV and telephone tech, he fix's my amps when they brake down so here is my question.
1. Does everybody think that a silver face should be converted to a black face?
2. Is there a place where I could find out what is needed and how to perform these changes and maybe my friend could do it for me, he loves working on amps and doesn't really have anything to do anymore.

I know allot of you do these changes and I wish I could afford to send it to you but this is kind of a freind thing and would make him happy to do it if he can.
Any and all advice is welcome.
Thanks again for all the help so far.
DR

RussBert · February 7th, 2006, 09:00 PM

Quote:

1. Does everybody think that a silver face should be converted to a black face?

No, some prefer the SF's

Quote:

2. Is there a place where I could find out what is needed and how to perform these changes and maybe my friend could do it for me, he loves working on amps and doesn't really have anything to do anymore.

Download a BF AB964 Vibrolux Reverb schematic and layout, and make your amp "just like it"

jjmantele · February 7th, 2006, 10:23 PM

There are different categories of "Blackfacing." The bias control setup, the phase inverter resistors, and some other stuff. I would go with a "combo" bias setup if I had a "SF" type bias to start with. The "combo" type keeps the bias "balance" feature while adding the overall bias "level" control.

I changed my input cap to the PI to the "BF" value on my '71 SFDR only after changing the speaker. Plenty of bass to go around with the BF value cap.

Each change or set of changes should be considered separately IMHO. And performed one at a time so you know what is an improvement and what is not for you.

H-man · February 8th, 2006, 05:09 PM

I recently acquired a '75 SF Vibrolux on eBay. It sounded OK but the cabinet (not finger jointed) was a little ratty and the original speakers were showing their age. I also like more clean headroom than it provided. So, I contacted David Allen ( www.allenamps.com ) and followed his recommendations. I pulled the chassis and shipped it to him. Among other things, he blackfaced the circuitry, installed a linear taper volume pot, new caps, 3 prong power cord, removed the pull boost and performed general maintenance. He also put it in a new retro vibrolux cabinet (finger jointed pine) with 2 10" Eminence Rajin' Cajun Speakers and new replica Fender blackface faceplate. Was it cheap? No. Was it worth it? More than worth it to me. Once the speakers were broken in I took it out for a real test drive - on a live gig. Sounded great and looked great not just to me but band mates as well. This amp is my new #1 for all except large / outdoors venues where I'll use my blackfaced (by David Allen) '69 SF Twin Reverb. I am a very satisfied customer. Even if you do not use his services I am sure he can point you in the right direction. He also sells parts that enable you to do it yourself (or in this case your friend). Good luck.

DAVIS T. BONE · February 8th, 2006, 10:17 PM

I have to second the motion re: David Allen at allenamps. He converted my Deluxe Reverb to BF + modded the normal channel. He is great to work with and the results are worth the effort of shipping a chassis to him. Highly recomended.

hmx1 · February 10th, 2006, 11:14 AM

Quote:

Originally Posted by H-man

I recently acquired a '75 SF Vibrolux on eBay. It sounded OK but the cabinet (not finger jointed) was a little ratty and the original speakers were showing their age. I also like more clean headroom than it provided. So, I contacted David Allen ( www.allenamps.com ) and followed his recommendations. I pulled the chassis and shipped it to him. Among other things, he blackfaced the circuitry, installed a linear taper volume pot, new caps, 3 prong power cord, removed the pull boost and performed general maintenance. He also put it in a new retro vibrolux cabinet (finger jointed pine) with 2 10" Eminence Rajin' Cajun Speakers and new replica Fender blackface faceplate. Was it cheap? No. Was it worth it? More than worth it to me. Once the speakers were broken in I took it out for a real test drive - on a live gig. Sounded great and looked great not just to me but band mates as well. This amp is my new #1 for all except large / outdoors venues where I'll use my blackfaced (by David Allen) '69 SF Twin Reverb. I am a very satisfied customer. Even if you do not use his services I am sure he can point you in the right direction. He also sells parts that enable you to do it yourself (or in this case your friend). Good luck.

Hey thanks allot, great tip.
He sure is a nice guy, he has emailed with several different ideas all within a day.
Thanks again,
DR

February 7th, 2006, 08:45 PM	#1 (permalink)
hmx1 TDPRI Member Join Date: Apr 2005 Posts: 43	converting a silver face vibrolux to a blackface Hi Guy's, I appreaciate all the answers to my vibrolux questions and now I have more... LOL I have a friend who is a retired TV and telephone tech, he fix's my amps when they brake down so here is my question. 1. Does everybody think that a silver face should be converted to a black face? 2. Is there a place where I could find out what is needed and how to perform these changes and maybe my friend could do it for me, he loves working on amps and doesn't really have anything to do anymore. I know allot of you do these changes and I wish I could afford to send it to you but this is kind of a freind thing and would make him happy to do it if he can. Any and all advice is welcome. Thanks again for all the help so far. DR __________________ Blues Power, Can you dig it

February 7th, 2006, 10:23 PM	#3 (permalink)
jjmantele Tele-Holic Join Date: Aug 2003 Location: New Jersey Posts: 850	BF There are different categories of "Blackfacing." The bias control setup, the phase inverter resistors, and some other stuff. I would go with a "combo" bias setup if I had a "SF" type bias to start with. The "combo" type keeps the bias "balance" feature while adding the overall bias "level" control. I changed my input cap to the PI to the "BF" value on my '71 SFDR only after changing the speaker. Plenty of bass to go around with the BF value cap. Each change or set of changes should be considered separately IMHO. And performed one at a time so you know what is an improvement and what is not for you. __________________ JJman If it says "Vintage" on it -it isn't.

February 8th, 2006, 05:09 PM	#4 (permalink)
H-man TDPRI Member Join Date: Mar 2003 Location: New Market, MD Posts: 13	Vibrolux conversion I recently acquired a '75 SF Vibrolux on eBay. It sounded OK but the cabinet (not finger jointed) was a little ratty and the original speakers were showing their age. I also like more clean headroom than it provided. So, I contacted David Allen ( www.allenamps.com ) and followed his recommendations. I pulled the chassis and shipped it to him. Among other things, he blackfaced the circuitry, installed a linear taper volume pot, new caps, 3 prong power cord, removed the pull boost and performed general maintenance. He also put it in a new retro vibrolux cabinet (finger jointed pine) with 2 10" Eminence Rajin' Cajun Speakers and new replica Fender blackface faceplate. Was it cheap? No. Was it worth it? More than worth it to me. Once the speakers were broken in I took it out for a real test drive - on a live gig. Sounded great and looked great not just to me but band mates as well. This amp is my new #1 for all except large / outdoors venues where I'll use my blackfaced (by David Allen) '69 SF Twin Reverb. I am a very satisfied customer. Even if you do not use his services I am sure he can point you in the right direction. He also sells parts that enable you to do it yourself (or in this case your friend). Good luck.

February 8th, 2006, 10:17 PM	#5 (permalink)
DAVIS T. BONE TDPRI Member Join Date: May 2005 Location: South Central Pa. Posts: 58	SF to BF conversion I have to second the motion re: David Allen at allenamps. He converted my Deluxe Reverb to BF + modded the normal channel. He is great to work with and the results are worth the effort of shipping a chassis to him. Highly recomended.