Dave Roffey  gives us a picture of the kind of research, experimentation and cross-fertilisation that was going on.  This wasn’t just with other designers and  companies, but with the actual manufacturers and designers of components like the transfomers;

“..Technically, for those times, the design of the valve phase-shift tremolo was an innovation. If that had been worked on, ‘phasing’ would have been around years before it actually appeared. I remember  (in the haze of it all) doing a three pot twin t(ee) filter in a foot pedal, which was the closest thing in those days.

Mullard, Brimar and the Williamson KT88 (400W) all contributed to the advances in those days, (more…)

Some good info on song/background  – http://en.wikipedia.org/wiki/She_Said_She_Said

This alternate take (‘Take 3’) of the Paperback writer shoot on youtube shows the proto amps a bit more clearly.  You can just see that the amp Lennon is miming by is actually the 7120 Bass.  One of the most memorable guitar riffs recorded, this was probably Paul using the new 7120 with a Rush Pep box.

This vid has the guitar track isolated –

David Cole would test the amps, along with the other amps & equipment made by Triumph.  He remembers a final-assembly on Fridays, when “…it all came together,  panels chassis and boxes, to get them out by the door to be shipped off.  I remember some panels being fitted towards the end ( to avoid damage during production ), so the control switches/inputs/lights had to be taken off and then laboriously re-attached.   We also made wha-wha pedals, they came from somewhere else and were badly made – they were dumped at Triumph for Rosetti.   Capacitors would fall off at the touch..we went through them fixing them up, they were in plain boxes with no paint.”

After arriving at Vox, they were given a final test.  Small stamps can sometimes be seen on the chassis; these could be from JMI, or maybe even earlier, from the original chassis plinth production.

round mark where chassis has been stamped, either during production or inspection

A small inspection tag would finally be added certifying it had been signed off.  One of these can be seen on the Beatles 730 in Abbey Road, attached to the back of the amp.

inspection tag on back of a ul-460

inspection tags on Beatles 730 amp

Close-up of Beatles 730 tag

similar tags from a Defiant

Ron Babbage started at Triumph in the wiring shop, but moved on to helping manage various projects.   He recalls that Triumph had the two buildings, either side of a music shop. “The metal fabrication part was on the medical side (to the left of the central shop). The Wiring Shop was under the building on the right. Walking around the back of the shop, there was a little garden area..metal stairs led to an alley, with a ramp up to the back of the Orchid, and a car parking area.

My first day was spent scraping and cleaning capacitors..with cuts and blisters on my fingers I thought ‘I’m never going back there again’, but persevered. I remember Dave Roffey, I think he might have been developing a reverb pedal/box. Bands would sometimes ask to test out equipment, usually at the weekends; you’d ask Geoff for permission and overtime and he’d say yes, go on, but I don’t remember getting paid in the end. I did get some extra work drilling holes for circuit boards..Rooke (Brooklands) heard, and asked if I could do the same for him. I managed in the end to save enough to buy a Morris Minor. One day Andy Fairweather-Low wanted to test out some amps at the Orchid, so 3 of us set it up and listened to him. He’d parked his Jensen Interceptor in my space though, and when I automatically reversed out as usual I hit an r.s.j. that was supporting a canopy, which fell and dented my car…! Geoff would give bands equipment,and then when the bands broke up he’d offer them a job – I seem to remember a couple of guys from Geno Washington’s band joined us, Alan Griffin was the guitarist and there was the drummer too.”

Andy Fairweather-Low was recalled by Dave Roffey too; “.. I remember going to see Andy Fairweather-Low when the band were staying in Zsa Zsa Gabor’s flash log cabin on an exclusive London ‘estate’, before a tour. Bit of promo for Triumph gear. He had a pretty rare original Dobro slide guitar that I remember being impressed by”.

Production at Triumph seems to have been pretty variable, with different ideas and directions being tried out. Roger White and David Earp worked on ac50s and ac100s in the mid-60s.  Then, when work got slack, they were ‘lent out’ to Brooklands, the nearby company that made the faceplates (and later on circuit boards for solid-state models). As well as 7/4 series panels, Brooklands made panels for the vox domino & ac4. Edward Rook (Brooklands) had gone into screen printing; panels were sprayed, then fed by conveyor through a baking unit.

( Initials on ac50 chassis, Roger White, & probably his friend David Earp, click to enlarge )

Before moving to Brooklands, Roger and David worked on amps like the ac50 for supplying to Vox. Roger  was there roughly from 1963-66; he remembers his first pay-slip as being for “.. 3 pounds, 17 shillings  and sixpence, as it wasn’t a full week.  I’d go through boxes of el34s, matching good push-pull pairs…I’d test them, making sure they got to 50 watts, the valves just glowing cherry red, before the sine wave started to flatten off on the scope. We used to stand the little ones up on their sides; they’d store a charge though,  and we soon learnt not to pick them up by the transformer after some nasty shocks.

I remember the reverb units; ceramic cartridges with a bit of bent wire, coiled & soldered to the head of a brass OBA or 2BA bolt. There was total feedback on the first one, until they realised they needed to wind it in one direction towards the OBA/2BA, then in the opposite direction to the other end.

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These reproduction cabinets are made from 9 ply, cabinet grade 3/4” plywood. The measurements for each cab is 42” X 29” X 13”. The measurements were taken from an original 4120 cabinet that resides in the UK (Thanks Mike Handley!!). The back panels are made from 3/8” thick Baltic Birch, as this is a much better grade of wood that you’d find at a building materials store and it is a true 3/8” thick. The building supply 3/8” plywood isn’t a true 3/8” thickness and is way too flimsy for back panel usage.

MEASUREMENTS:
Cabinet Material: ¾” Cabinet grade plywood, 7 to 9 ply.
Rear panel material: 3/8” Baltic Birch.
Gold Cabinet Piping: 2 1/8” inside from each edge.
Piping Channel depth: 3/32”.
Piping Channel width: 1/8”.
Hand Wheel trolley mounting holes: 12 ¼” down from top of side.
Rear input jack (4120 cab): 6 ¾” down from top center.
Rear input jack (7120): center of top rear panel.
Front Baffle mounting strips depth, in from front edge: 1 ¼”.
Rear Panel mounting strips depth, in from edge: 3/8 to 7/16”.
Midax Horn baffle location: Down from top – 6” / In from the side – 4 ½”.
Midax Horn cutouts: 2 ½” X 5 5/8”.
12” Speaker baffle holes: 11” circle.

You will need approx 4 yards of Tolex; cabinet is approx 12’ around (tolex is usually cut from 54” high rolls).
You will need 17 yards of .080” Gold Piping = approx 51’.
8 yards of White baffle piping.
3 yards of VOX grillcloth.

Cabinets are 42” X 29” X 13” .
4120 Rear Panel: approx 40 5/16” X 27 5/16”.
16 Speaker mounting baffle machine screws & nuts: 1 1/4” to 1 ½” long.
20 2 /1/4” X 10/32 Midax Horn mounting machine screws & nuts.

CLICK ON THE THUMBS FOR LARGER IMAGES

I went ahead and drilled the side panels for the trolley mounts just in case an original or a re-issue 7120 trolley should ever become available. Not likely, but the holes are there under the tolex just in case.

The other tolexed cabinet in this 1st set of pics is a ‘Supreme’ donor cabinet that I had in my collection. I used this for the inside cabinet measurements and for the original baffle hardware which I used on the 7120 build. The 4120 build used all new mounting hardware.

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I applied the tolex all the way around the cabinet and allowed for the seam to be at the bottom center. I started at the bottom and made my way around the entire cabinet, gluing the center section down with titebond and smoothing it out with a ‘J’ roller. Allow for several inches on each side to allow for tucking and trimming when doing the final gluing / fitting. Rather than splitting the tolex down the center of the gold piping channel, I elected to use hard maple strips to press the tolex and the gold piping into the piping channels. The ‘splitting’ technique works well, but I found that using this alternate method worked just fine. Then I used contact cement to glue down the outside sections of tolex to the cab. Before I started gluing the tolex, I used black spray paint to spray the piping channel(s) just in case I decided to split the tolex. Not really needed, but I did it anyway. To get a perfect fit when the pieces meet on the bottom, overlap the pieces and using a razor blade and a straight edge, make a cut thru both pieces. After you make this cut, both pieces will fit together perfectly. You can staple together the edges until the glue dries to insure the edges stay together and don’t shrink back from each other. Then remove the staples. You should have a perfect seam and the staple holes won’t be visible.

Rather than use paint on the baffles, I decided to use jet black stain mixed with standard rubbing alcohol applied with a paint sprayer. Using this allows the ‘inside’ cabinet view of the baffle to have that ‘aged’ look where you can still see the woodgrain, much like the inside of most vintage JMI baffles. I painted the outside portion of the baffle semi-flat black.

There is a pic of the 7120 / 4120 baffle next to my ‘donor’ Supreme baffle; I did this to show that the cabinets and baffles of these cabinets are slighty larger than AC-100 Deluxe and Supreme baffles.

You will want to do a trial fitting of the baffle to the cabinet in order to drill the baffle mounting holes. Usually it’s 4 or 5 at the top/bottom and 3 at each side. Run your white piping around the outside of the baffle using a few temporary staples to hold it in place. Do your measurements for your mounting holes, as you want these to be pretty even all the way around. When it’s fitted properly, drill your initial mounting holes where you’ve measured the proper spots. This way, when you install the assembled baffle, all of your holes will line up. You will also want to enlarge the mounting holes on the mounting strips on the inside of the cabinet, probably up to ¼” or even a tad larger if need be. This will give you some ‘wiggle’ room when fitting the baffle; these larger holes won’t be seen from the inside of the cabinet, as you’ll use small ‘fender’ washers when you bolt everything down.

I used VOX ‘scrim’ material glued over the front of the baffle with water thinned titebond. This dries clear and works great. You cut this scrim right to the edge and doesn’t need to be folded over to the rear. Make sure it’s tight over the front and secure with staples as needed. Remove these after the glue dries, usually overnight is best.

After the scrim is on, then move on to fitting the grillcloth. I used 1960’s vintage USA ‘Thomas Organ’ vintage NOS grillcloth, as I had a small supply of this that I had saved that had been cut from a roll that I owned & sold many years ago. I had just enough to do both baffles. You will have to lay it out and staple it down to the REAR edges of the baffle with the cloth folded over & around the sides. (more…)