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previous: Doug I was thinking about trying to buil... -- 11/11/1999 8:27 PM

Re: EF-86 & Dr. Z Route 66 Questions

11/12/1999 2:56 AM
DR.Z	Re: EF-86 & Dr. Z Route 66 Questions First, I would like to say I truely enjoy this BBS, it is refreshing to see info shared, without all the BS, and self promotions as on other BBS's and newsgroups. I 'm happy to contribute, and with this header I could'nt refuse. I won't disclose the schematic for the Rt.66, for one it is so simple. The parts count on the turret board is 26 and that includes the bias power supply. But I will try an answer Dougs questions and give some insite into the design. A good place to look for an EF-86 circuit is on the Svetlana website. It is very close to the 66's, tho I connect the shield pins 2 and 7 to ground not to the bias . The early 66's used NOS EF-86's, which presented a problem each brand had a differant responce. I found some to be bright and articulate while others were warm and thick. Which made some great for single coils and others good for humbuckings. I sold a 66 to Boz Scaggs, while building it I pulled out some old Boz LP's and heard a very rich thick tone , so I opted for a dark plate Mazda EF-86 for his amp. I recieved a call for Boz and he said the amp was too dark for his LP, I told him that the EF-86 is the whole pre-amp in the 66 and by swapping it you could alter the responce of the amp. He said he had a tube guy with many types of EF-86's and he would try a few. He called me back and said he installed a Svetlana in the amp and it was perfect. Needless to say I was supprised, I bought some and found there responce to be very balanced, and no longer did I have to adjust the amp for the type of guitar used. It was a win win situation for me a currant production low cost EF-86, no noise problems, that sounded great. Doug there are other amps that use the EF-86, the Selmer Zodiac, as well as the AC-30/4 check them out as well. I do dig the unique timbre of the EF-86, and it is refreshing to use something other than a 12AX7. Also the EF-86 can handle large input signals and remain very linear, excellant for stomp box inputs. The PI on the 66 isn't a standard long tail, I believe a big part of the tone is from the ZNFB UL output. Which Ken and I belive in, UL's have gotten such a bad rap from Fender's attempt at it that it is a uphill battle, if only they would have done it right. I will add that UL's arn't for every tube type, and this is the only currant production amp I build with a UL. One thing Ken and I don't agree on is the final coupling caps, on the 66 I use .15 uF oil filled caps. I hope this has helped answer some questions, I 'm getting a bit tired of typing, look for part II, coming soon. DR.Z

11/12/1999 2:56 AM

DR.Z

Re: EF-86 & Dr. Z Route 66 Questions

First, I would like to say I truely enjoy this BBS,
it is refreshing to see info shared, without all the
BS, and self promotions as on other BBS's and newsgroups.
I 'm happy to contribute, and with this header I could'nt
refuse.

I won't disclose the schematic for the Rt.66, for one
it is so simple. The parts count on the turret board
is 26 and that includes the bias power supply. But I will try an answer Dougs questions and give some insite into
the design.

A good place to look for an EF-86 circuit is on the Svetlana
website. It is very close to the 66's, tho I connect
the shield pins 2 and 7 to ground not to the bias .
The early 66's used NOS EF-86's, which presented a problem
each brand had a differant responce. I found some to be
bright and articulate while others were warm and thick.
Which made some great for single coils and others good
for humbuckings. I sold a 66 to Boz Scaggs, while building it I pulled out some old Boz LP's and heard a very rich thick tone , so I opted for a dark plate Mazda EF-86
for his amp. I recieved a call for Boz and he said the amp was too dark for his LP, I told him that the EF-86 is the
whole pre-amp in the 66 and by swapping it you could alter the responce of the amp. He said he had a tube guy with many
types of EF-86's and he would try a few. He called me back
and said he installed a Svetlana in the amp and it was perfect. Needless to say I was supprised, I bought some
and found there responce to be very balanced, and no longer did I have to adjust the amp for the type of guitar used.
It was a win win situation for me a currant production
low cost EF-86, no noise problems, that sounded great.

Doug there are other amps that use the EF-86, the Selmer
Zodiac, as well as the AC-30/4 check them out as well.
I do dig the unique timbre of the EF-86, and it is refreshing to use something other than a 12AX7.
Also the EF-86 can handle large input signals and remain
very linear, excellant for stomp box inputs.

The PI on the 66 isn't a standard long tail, I believe
a big part of the tone is from the ZNFB UL output.
Which Ken and I belive in, UL's have gotten such a bad
rap from Fender's attempt at it that it is a uphill
battle, if only they would have done it right.
I will add that UL's arn't for every tube type, and this
is the only currant production amp I build with a UL.
One thing Ken and I don't agree on is the final coupling caps, on the 66 I use .15 uF oil filled caps.

I hope this has helped answer some questions, I 'm getting a bit tired of typing, look for part II, coming soon.

DR.Z

Replies:

Morris Dr. Z, thanks for your excellent po... -- 11/12/1999 3:11 AM
MJ Harnish Dr. Z, Thanks for the coo... -- 11/12/1999 2:39 PM
Ken Gilbert q{One thing Ken and I don't agree o... -- 11/12/1999 2:47 PM
Scott Dr. Z,I have to say... -- 11/12/1999 4:30 PM
Doug Thanks a lot for your insight, and ... -- 11/12/1999 4:31 PM
Gus FWIW I have a friend that mods heat... -- 11/12/1999 4:56 PM
Trace q{First, I would like to say I true... -- 11/13/1999 6:37 PM