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Thread: Favorite AC30 tone ?

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    Bent Member Chuck H's Avatar
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    Favorite AC30 tone ?

    I'm not even a player that would use an AC30 as my main amp. But they do have some magic tone in the right hands and setting. Iconic really. Always getting the job of "amplifier" done well, but sometimes instantly recognizable with some exceptional qualities. So much so that I'm sure many here, like me, would like to have one just for the fun of it. The song that REALLY makes me want to build or buy one is American Girl (Tom Petty and the Heart breakers). There are others too, but that's really the song that get's my Jones on. So...

    Even if you're not an AC30 player I know it's probable that you've heard an AC30 tone you'd love to have. If it's a commonly known tune then I suppose just a mention is good. If it's more obscure then a link would be great.

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    Old Timer Leo_Gnardo's Avatar
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    Since you're posting first thing in the morning, at least for those of us in North & South America, I'll mention my favorite "reveille" tune, "And Your Bird Can Sing." Double tracked, for double the fun. If that isn't an AC30... well it might be an AC15.

    An anecdote I heard some years ago: George was being interviewed, he was asked how the Beatles got those glorious guitar tones. Sez George, "We thought our tone was rubbish." HA! Rubbish indeed! Sure, that tone drilled its way into millions of ears, attached to millions of brains that thought "I must buy that record NOW!" then dug into their pockets & did exactly that. Rubbish, ain't nothin' like it.

    Have a listen:


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    I was turned on to the AC30 by Rory Gallagher's strat sound with "The Taste". Had seen the band at the 1970 Isle of Wight festival. Soon after I bought my first AC30 and still have it. While in London I also got me a Hornby-Skewes treble booster somewhere on Shaftesbury Ave because I had heard that Rory uses one.

    Another AC30 player having a great (and completely different) sound is Brian May (Queen).
    Many UK players (Clapton, Beck, Page, Blackmore...) used AC30s in their early years.

    I always thought of the AC30 as a great sounding amp for single coil guitars. For my Gibsons I prefer a BF Fender + Zendrive or TS-9.

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    Senior Member Pedro Vecino's Avatar
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    Quote Originally Posted by Helmholtz View Post
    I always thought of the AC30 as a great sounding amp for single coil guitars. For my Gibsons I prefer a BF Fender + Zendrive or TS-9.
    A good SG with an AC30 is also a very classic sound for pop/rock. The hammering highs of the SG combine very well with it.

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    Senior Member nevetslab's Avatar
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    Quote Originally Posted by Pedro Vecino View Post
    A good SG with an AC30 is also a very classic sound for pop/rock. The hammering highs of the SG combine very well with it.
    And a killer amp for mating up with the Rickenbacker 12 string Deluxe Blonde Hollowbody!

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    As with any amp, the sound of an AC30 strongly depends on its speakers. My 1970 AC30 came with late silver Celestion alnicos. They were incredibly loud/efficient but lacked the sweet highs of the earlier alnicos (I later had a chance to exchange them). Late 60s early 70s AC30s came with a number of different speakers: Celestion alnicos, 20W or 25W Celestion Greenbacks, Goodmans, and probably also Fanes (the AC50 I had before the AC30 used Fanes - didn't like them).
    My favorite speakers are the earlier Celestion alnicos and the (less efficient) G12M20 greenbacks.

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    Supporting Member The Dude's Avatar
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    Quote Originally Posted by Helmholtz View Post
    ......Another AC30 player having a great (and completely different) sound is Brian May (Queen)......
    'nuff said!


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    Bent Member Chuck H's Avatar
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    I read an interview with Mike Campbell where he said that American Girl was recorded with the amps that were in the studio. Tom played through a Super Six and he played through a tweed Deluxe. Bah!!! I don't buy it. The rhythm tone is so classic AC30 it's unmistakable. Dialed in just right they do something that I've never heard other production amps do. They "get under the note" in those ringy HF frequencies and lightly compress everything else around them. You can't miss it when you hear it. But it WAS recorded a long time ago so I'll give him a pass

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    My fave AC30 recorded tone (sorry Brian May again, though it's a bit different to his 'signature' tone) http://www.youtube.com/watch?v=ZZyhS5beQc8

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    Quote Originally Posted by Leo_Gnardo View Post
    Since you're posting first thing in the morning, at least for those of us in North & South America, I'll mention my favorite "reveille" tune, "And Your Bird Can Sing." Double tracked, for double the fun. If that isn't an AC30... well it might be an AC15.

    An anecdote I heard some years ago: George was being interviewed, he was asked how the Beatles got those glorious guitar tones. Sez George, "We thought our tone was rubbish." HA! Rubbish indeed! Sure, that tone drilled its way into millions of ears, attached to millions of brains that thought "I must buy that record NOW!" then dug into their pockets & did exactly that. Rubbish, ain't nothin' like it.

    Have a listen:

    That wasn't an AC30. It was two Epiphone Casinos through Vox UL 7120 amps, which had a solid state preamp and a tube output section.

    http://www.voxshowroom.com/uk/amp/7120.html

    https://www.youtube.com/watch?v=YZaa...&index=76&t=0s

    https://www.youtube.com/watch?v=cAtu...Q95fw&index=68

    The whole Revolver album used those amps. Very unique tone. Stephen Walsh out of the UK makes clones of these amps, though I think that he is only selling in the UK currently. R.G. Keen sells a preamp board for these amps that you would have to stuff yourself. You would also have to find a solution for the reverb. The last time I talked to R.G. about it that was the case anyway. I haven't talked to Stephen Walsh about the ones he is building much, but they look and sound great from the youtube videos!

    Greg

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    Last edited by soundmasterg; 03-08-2019 at 06:49 AM. Reason: added links to UL 7120

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    As a side note, an interesting thing about the Beatles and Vox tones is that so many people assume they used AC30's for most of their stuff when the reality is quite different.

    They used AC30's on the first album (Please Please Me) with a Quad hifi amp used for bass.

    The second album (With the Beatles) was some AC30 for guitar but was mostly AC50 and bass was a mixture of AC50 and Vox T60 solid state. There may have been some AC100 (80100) use for bass also, though the cabinet had a 15 and a 12 in it rather than two 15's like some later cabinets.

    The third album (Hard Day's Night) was AC100 for bass and AC50 and AC100 for guitar.

    Beatles for Sale, Help, and Rubber Soul were AC100 for the most part, though a piggyback Fender Bassman started to come into use also for both guitar and bass.

    Revolver was the Vox UL 7120 and 4120 amps with the Fender Bassman in use too.

    Sgt. Pepper used the Vox UL hybrid tube/solid state 430 and 730 amps, along with some solid state Defiants. There was also a Selmer Treble N Bass in use for McCartney's solos on some songs.Recording the Beatles : The Studio Equipment and Techniques Used to Create Their Classic Albums

    Magical Mystery Tour was much the same as Pepper.

    After MMT they largely switched to Fender amps for guitar and bass.

    The very excellent book Recording the Beatles details a lot of the equipment in use, along with techniques and personnel present. Its expensive but worth it!

    Recording the Beatles : The Studio Equipment and Techniques Used to Create Their Classic Albums

    Greg

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    Last edited by Boss; 03-10-2019 at 11:09 AM.

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    Here is one of my favorite AC30 tones around...there are MANY others though.

    Greg

    https://www.youtube.com/watch?v=S0kTkxhyWNo

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    Senior Member Pedro Vecino's Avatar
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    Although there appears with makeup this is my favorite. With an AC15, more easily manageable with volume.

    https://youtu.be/_5001SDOFHk?t=240

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    Quote Originally Posted by soundmasterg View Post
    That wasn't an AC30. It was two Epiphone Casinos through Vox UL 7120 amps, which had a solid state preamp and a tube output section.
    Well dog my cats... but dam' if that isn't some identifiable VOX tone anyway.

    As far as other amps, studio photos do reveal a cream Bassman piggyback rig, and later on a variety of Fenders as you mention.

    Also, as an owner of two fine Vox amps, both 60's AC50 and AC100, lots of terrific tone to be had there as well.

    Does "Recording The Beatles" show Geoff Emerick's revolutionary method of using a bass speaker as a microphone? Adds some lowdown lows to bass and maybe kick drum tracks too. That guy was full of kool tricks.

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    I think there’s a little magic to good EL84 amps in general. The little 5watt Class As scream. My go to club amp for years is a EL84 push/pull open back combo with a single good 12” speaker... basically half an AC30 in general (Ac15, Marshall 18 watt, and variations). To hit that raging sweet spot an AC30 is a bit loud in most clubs anymore for me. I know there are various nuances. But for a single amp that’s very versatile at a sane stage volume in small clubs that you can record and practice with as well as easily haul around.. can’t be beat.

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    Bent Member Chuck H's Avatar
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    Quote Originally Posted by Leo_Gnardo View Post
    Well dog my cats... but dam' if that isn't some identifiable VOX tone anyway.
    I thought the same thing. There's a little dynamic response missing (I think) but compared to other recording of the era it's no great shakes. Just another example of how good musicians can "find" the music with whatever they happen to be using at the time. I (apparently) think that Mike Campbell playing his Broadcaster through a 5E3 sounds like an AC30!?! Who knows WHAT they did in the studio in either case.

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    Quote Originally Posted by Leo_Gnardo View Post
    Well dog my cats... but dam' if that isn't some identifiable VOX tone anyway.

    As far as other amps, studio photos do reveal a cream Bassman piggyback rig, and later on a variety of Fenders as you mention.

    Also, as an owner of two fine Vox amps, both 60's AC50 and AC100, lots of terrific tone to be had there as well.

    Does "Recording The Beatles" show Geoff Emerick's revolutionary method of using a bass speaker as a microphone? Adds some lowdown lows to bass and maybe kick drum tracks too. That guy was full of kool tricks.
    Yes that whole UL period (Revolver, Pepper, MMT) has a very identifiable sound, and it is mostly Vox for guitars and bass.

    I absolutely love vintage JMI AC50's and AC100's! Count me as officially jealous . I built myself an AC100 clone but haven't duplicated the AC50 yet. I have a Korg AC30 with Celestion Blues and owned it since new (1993). Its currently out of order but it works well and sounds good, though not on the same level as a vintage one.

    I did mention there was a piggyback Bassman in use pretty early on, and yes you will see it in many photos. George Harrison apparently loved the amp and inherited it after the breakup.

    "Recording The Beatles" doesn't show pictures of the bass speaker as microphone technique, but they do mention it in there. It is one of the best books I've ever gotten with so much interesting info in it about the equipment used, microphones, sessions, gear, personnel, etc. Definitely worth the price, as is the book on Vox amps.

    Vox Amplifiers: The JMI Years

    That one is probably the most complete book ever written on any amp manufacturer.

    Greg

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    Quote Originally Posted by Chuck H View Post
    I thought the same thing. There's a little dynamic response missing (I think) but compared to other recording of the era it's no great shakes. Just another example of how good musicians can "find" the music with whatever they happen to be using at the time. I (apparently) think that Mike Campbell playing his Broadcaster through a 5E3 sounds like an AC30!?! Who knows WHAT they did in the studio in either case.
    Yeah I've heard Mike Campbell used his Broadcaster and a vintage 5E3 on a lot of their stuff. I can hear that in those tones you mentioned. I have a real 1956 5E3, and a Jap reissue Tele with a Stephens Design broadcaster set....and I think it is probably a similar sound to that one you describe. Mike Campbell is such a tasty player too...very much in the same house as George Harrison as far as fitting into the song, having good tone and chops, etc.

    Who knows what anyone uses in the studio or what effects are added from the studio gear, but the ones I mentioned about the Beatles are pretty well known and documented in many places. I had heard that Tom Petty and the Heartbreakers used Vox Super Beatles on some of those early recordings too....they did use them on tours, but I can't imagine using them in the studio....they are f***ing loud and pretty sterile.

    Greg

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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by soundmasterg View Post
    Yes that whole UL period (Revolver, Pepper, MMT) has a very identifiable sound, and it is mostly Vox for guitars and bass.

    I absolutely love vintage JMI AC50's and AC100's! Count me as officially jealous .
    I was officially lucky.

    I built myself an AC100 clone but haven't duplicated the AC50 yet.
    Hope you allowed plenty of extra breathing space for the output tubes. On the original item - AC100 - what were they thinkin'? Way small box to stuff 4 output tubes into. I run mine typically 1/2 to one hour at a time. Long enough for a Beatles concert back in the day. No way either amp can out shout a stadium full of screaming girls.

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    Bent Member Chuck H's Avatar
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    Quote Originally Posted by soundmasterg View Post
    I absolutely love vintage JMI AC50's... but haven't duplicated the AC50 yet.
    Yeah, you might want to get on that I built a customer order that switches between a BF preamp and an AC50 bright channel preamp into a pair of el34's in a 2x12 combo (using a pair of G12H Anni's). Add a reverb and bias wiggle trem. I tease this guy that he owns nicer amps than I do and I'm building them! The "Vox" channel is truly great to play through. It's not even "my" sound and I could just noodle with it all day. Totally worth building one if you want one.

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    Old Timer tedmich's Avatar
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    The AC30 is a versatile amp, always dug this sound, teamed with a 69 Les Paul Custom

    Always loved how the solo just drops in and out

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    My first amp was a second hand AC50 + original cab, bought around '68. I thoroughly compared it to the 1970 AC30 before I traded it. Never looked back.
    I mean the AC50 was loud and powerful, but my strat leads just wouldn't sing no matter what I tried (Fuzz Face clone, treble booster). Might have been partly due to the speakers (Fane?).

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    Quote Originally Posted by soundmasterg View Post
    ...I built myself an AC100 clone but haven't duplicated the AC50 yet...
    When you do, make sure to get the OT spec right, not just a regular EL34 50 watter. They're massive, the stack is 50% thicker than that of a Marshall.
    I've got the dimensions somewhere but can't put my hand on it at the mo
    I guess that they may be full power rated down to 40Hz, with a G12H loaded 4x12 they certainly sound excellent for bass.

    Re the AC30, I'm now pretty sure that the JMI schematics have an error, as the actual JMI's have C41 as 47nF rather than 0.005uF (V8 vib/trem mixer circuit) https://el34world.com/charts/Schemat...x_ac301960.pdf
    The Marshall design/built 90s Korg RI even copies the schematic error into the actual circuit! https://el34world.com/charts/Schemat...x_ac3093pr.pdf
    I guess that most every 'clone' does so too.

    Ironically, although it was something of a low point for the brand, the schematics from the Dallas-Arbiter and Rose-Morris era at least got that cap value right https://el34world.com/charts/Schemat...x_ac30dals.pdf
    https://el34world.com/charts/Schemat...x_ac301989.pdf

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    Bent Member Chuck H's Avatar
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    Quote Originally Posted by pdf64 View Post
    When you do, make sure to get the OT spec right, not just a regular EL34 50 watter. They're massive, the stack is 50% thicker than that of a Marshall.
    I've got the dimensions somewhere but can't put my hand on it at the mo
    I guess that they may be full power rated down to 40Hz, with a G12H loaded 4x12 they certainly sound excellent for bass.
    I used a 30W rated OT from a Fisher stereo amp. The amp puts out all of 50W but it's a guitar amp after all and the bandwidth is much more limited. Seems to be working great so far. Certainly not as burly as you describe. Not even as burly as a 50W Dagnall either. But sounds just fine. Then again, I don't have an actual AC50 on hand to compare it to. I don't know the Primary Z for the AC50 but the OT I used is the ubiquitous 6.6k.

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    I don't know the Primary Z for the AC50 but the OT I used is the ubiquitous 6.6k.
    Watch out for the screens with 6.6k. 2xEL34s are fine with a Zaa between 3.2k and 4k. Real pentode screens are more at risk than beam tetrode screens at high load impedance.

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    Quote Originally Posted by Helmholtz View Post
    Watch out for the screens with 6.6k. 2xEL34s are fine with a Zaa between 3.2k and 4k. Real pentode screens are more at risk than beam tetrode screens at high load impedance.
    Indeed and thank you! A phenomenon I became familiar with some time after that build. I can't remember now, but it's possible I moved up one on the OT secondary taps and have it wired for 3.3k. I can't say when I may get that amp back on the bench, but I will be checking for that when I do.

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    My notes are that this MkII dual channel AC50 (GZ34 rectified) OT had 175 (!) laminations in a 2.5" thick stack, 3.75x3". The ratio was 1:21 from the 8ohm tap, 1:15.2 across the full 15ohms, so a ~3k4 primary.
    By comparison, a Dagnall 784-139 used in 50 watt Marshalls has 72 laminations in a 1.44" thick stack, 3.75x3.14".

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    Quote Originally Posted by Leo_Gnardo View Post
    Hope you allowed plenty of extra breathing space for the output tubes. On the original item - AC100 - what were they thinkin'? Way small box to stuff 4 output tubes into. I run mine typically 1/2 to one hour at a time. Long enough for a Beatles concert back in the day. No way either amp can out shout a stadium full of screaming girls.
    Yes I built it into a Sovtek MIG 100U chassis and head box. I kept the Sovtek PT but used Heyboer OT and choke...and they are very nicely made and much like the originals. I made it have a 2nd channel with much higher gain, and the first channel is stock with 12AU7's etc. I put the preamp voltages in between the AC100 MK2 and the 80100, and made it switchable cathode boas and fixed bias. I had to change to larger wattage cathode bias resistors twice as I underestimated, and I had to change the values twice to get the bias current low enough that it wouldn't kill the power tubes over time. They ran those things hot! I had to redesign a couple things I did, and got distracted by car repairs and some other things, so it is still sitting on the bench waiting for me to finish it. It sounds just like an AC100 in the cleaner channel though!


    Yeah, you might want to get on that I built a customer order that switches between a BF preamp and an AC50 bright channel preamp into a pair of el34's in a 2x12 combo (using a pair of G12H Anni's). Add a reverb and bias wiggle trem. I tease this guy that he owns nicer amps than I do and I'm building them! The "Vox" channel is truly great to play through. It's not even "my" sound and I could just noodle with it all day. Totally worth building one if you want one.
    That sounds like a cool amp! Is it a BF PI and power amp also? When I do an AC50 I'll keep their complete design...preamp, PI, and power amp. Or maybe I'll take a trip to England and see if I can find a used one...haha.

    When you do, make sure to get the OT spec right, not just a regular EL34 50 watter. They're massive, the stack is 50% thicker than that of a Marshall.
    I've got the dimensions somewhere but can't put my hand on it at the mo
    I guess that they may be full power rated down to 40Hz, with a G12H loaded 4x12 they certainly sound excellent for bass.
    I am pretty sure Heyboer makes a great clone. Their AC100 clone OT was fantastic, and much better and bigger than a similar Marshall or the Sovtek that was on the chassis prior.

    Greg

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    Supporting Member tubeswell's Avatar
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    Building a better world (one tube amp at a time)

    "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by tubeswell View Post
    Oh yeah! Hank Marvin: the reason so many up & coming UK guitarists just had to get a strat. A bright red one, preferably. Great pick! Don't know if that's what he's using on this track, but he sure caught everyone's notice with that outlandish streamlined modern looking guitar in the very late 50's and early 60's.

    I was lucky to get to meet the man, twice.

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    Enjoy. Every. Sandwich.

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    Supporting Member tubeswell's Avatar
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    Quote Originally Posted by Leo_Gnardo View Post
    Oh yeah! Hank Marvin... Don't know if that's what he's using on this track, but he sure caught everyone's notice with that outlandish streamlined modern looking guitar in the very late 50's and early 60's.

    I was lucky to get to meet the man, twice.
    Pretty positive that’s the clean sound of an AC 30 with top boost through a pair of Alnico Blues.

    The AC30 was made for Hank.

    So you’ve met the man? What did he say?

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    Senior Member Pedro Vecino's Avatar
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    As a curiosity, I had one of the few models identical to the AC30 manufactured for Hank Marvin by JMI some years ago. Its price was astronomical. It was not damaged or anything like that. He simply brought it to me to supervise it.
    I quickly checked with my Fender and Gibson scopes that the bright channel did not sound as it should (very incisive, abnormal).
    After examining it thoroughly I found that the treble capacitor in the top boost module was a silver mica of 470pf instead of 47 (50)


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  33. #33
    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by tubeswell View Post
    Pretty positive that’s the clean sound of an AC 30 with top boost through a pair of Alnico Blues.

    The AC30 was made for Hank.

    So you’ve met the man? What did he say?
    Excuse please a moment of

    Once in summer '84 when the Shadows were rehearsing at Nomis in west London. Then again backstage '95 at the Shepherds Bush Empire. Both times introduced by Peter Frampton and yes Peter has his red Strat (don't tell anybody it's really a Fernandes) due to Marvin influences. Both times just a "pleased to meet you" from Mr. Marvin. Some ten years later Peter had Hank in studio as a guest artiste on his Grammy winning all-instrumental "Fingerprints" album. Something that should be in everyone's collection. YouTube here: https://www.youtube.com/watch?v=XKceZTYcqvA . FWIW I see there's now a re-release of Fingerprints with extra tracks. Gonna have to score a copy, that's for sure.

    Also not to be neglected, the rare "Theme From Nivram" from Frampton's Shine On collection:
    https://www.youtube.com/watch?v=fO6mHQ4BKG4. Composed via inspiration from England's guitar master, as your ears will quickly tell you.

    And this is not enough. This morning whilst snooping Shadows, I ran across their terrific version of Procol Harum's "Whiter Shade of Pale." After hearing all sorts of lame covers of this magnificent tune, it sure was a treat to hear what Hank & The Shadows did for it. All instrumental, as they do. Very expressive but not overplayed guitar. Clever score edits near the end keep it from going on too long. Now my 2nd fave version after the original. Have a listen here: https://www.youtube.com/watch?v=7rzCAjqoQfE

    OK, enough Let's find some more AC30 licks, I'll let yez get onto it.

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    Last edited by Leo_Gnardo; 03-11-2019 at 08:58 PM.
    Enjoy. Every. Sandwich.

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