Brenell Mk. 6 Stereo Reel Table Extra Pieces Function

[DMcMahon]

What are all these extra pieces for ?

David

[Boulevardier]

Those are the bits that make up the NAB spool adaptors. The grey metal discs and white plastic bits all fit together - concentrically one on top of the other and sit on the normal hubs. The black metal bits are the spool clamps, which fit over the assemblies after you've put the NAB spools onto the lower bits. It's not a very pretty arrangement, but typical of Brenell's "heavy engineering" approach to its tape decks - even the MK 6.

The spool clamps may not be particularly well manufactured - the two parts of mine came apart as soon as I started to use them - they are just "crimped" together. More like something you'd find on the railway!

Mike

[Ted Kendall]

I'd call it cheap as chips - the white plastic bits are dual purpose adaptors for NAB and AEG hubs, and don't adequately retain either.

[Boulevardier]

Originally Posted by Ted Kendall

I'd call it cheap as chips - the white plastic bits are dual purpose adaptors for NAB and AEG hubs, and don't adequately retain either.

Agreed. I think "crude" is the word I was groping for...

Mike

[DMcMahon]

Thank you, so the Mk. 6 Stereo is a 10.5" compatible machine.

I was unsure because the Brenell book refers to the Mk. 6M being 10.5" and there being a 601 variant that was 10.5"

David

[Boulevardier]

Originally Posted by DMcMahon

Thank you, so the Mk. 6 Stereo is a 10.5" compatible machine.

I was unsure because the Brenell book refers to the Mk. 6M being 10.5" and there being a 601 variant that was 10.5"

David

I'm not sure about any model numbers, David. When I ordered mine back in the 1970s, I just phoned them and told them what I wanted - 10.5" spools, 3 heads, and high speed. I've a feeling that the 10.5" versions were only made specifically to order, because of the different deck-plate drillings needed for the spool motors. The Mk 6 seems to be just a superficially tarted-up version of the Mk5 - just trying to look a bit more '1970s' than the distinctly '1950s' earlier versions.

Mike

[DMcMahon]

Mike, how do you rate the Mk. 6 perfomance ? good, bad or indifferent.

David

[Boulevardier]

David - Just to be clear, I didn’t have the full Mk 6 recorder. I had built the Mullard Type-C tape pre-amplifier (excellent circuit, but obviously only mono), and had been using this with an old Truvox deck. So, in 1972, I bought the MK 6 “bare” 10½-inch deck with three Bogen heads, and used it with the Type-C while I gradually constructed the Stuart stereo tape circuits that were published in WW about that time. So, as I say, I can only comment on the deck. By 1972, the only decks available for consumer purchase in “bare” form were the Brennel and, I think, the Magnavox-Collaro.
I have to say I was disappointed by the basic nature of the deck. By that time, the A77s had been around for about 5 years, and had raised the game considerably for tape decks. The totally ‘mechanical engineering’ nature of the Mk 6 left it miles behind this sort of competition, and AFAIR the deck still cost over £100 in 1972 (and according to ONS calculator that's equivalent to over £1,300 today). I didn’t have the kit to measure wow and flutter, etc, but I had no reason to doubt Brennel’s spec. for the MK 6 for the basic play/record tape transport function. The fast wind/rewind functions on my 10½” version were, IMHO, attrocious – just simple spring-loaded levers with small cork pads – no match for those 10½-inch aluminium NAB “flywheels”. And the decks “Start” function was catastrophic at 15 ips - by the time the take-up spool got up to speed, the capstan had already fed about 15” of tape through the head channel, and the loop of tape that formed got snatched up and usually vanished between the tape already on the spool and the spool flanges. The only solution was to juggle with the Start and Pause controls, which left the take-up spool powered and the tape under tension when paused.
The Papst capstan motor on mine went o/c (completely unprovoked) about three years from new. I was living on a postgraduate grant at the time, and it was ages before I’d saved enough to replace it. Of course, the high speed and static tape guides, pressure pads, etc produced enormous and rapid wear in the tape path - even the end-of-tape sensing lever got almost worn through.
The other major problem I had was the flywheel-shaft upper bearing, which failed after about 10 years. This was a sintered sleeve bearing, and is OK for horizontal operation. However, if the deck is run vertically, the weight of the flywheel bears down laterally on one point at the bottom side of the static bearing and wears the bore into an oval. Brennel had gone the way of all flesh by the time this happened, and I had to get a work-colleague with a lathe to machine an aluminium housing to bolt to the deck plate and carry a ball-race that would fit midway up the flywheel shaft. In my view, it should have been designed with a ball-race.
All these things just reinforced my view that Brennel had just very superficially tarted-up the old design of the deck, and found the cheapest way possible to introduce the features that the modern, properly designed decks offered.
Have to stress that I’m not in any way a professional in this area, and this should just be taken as a lay view of the deck. Sorry I can’t give any view on the Mk 6’s electronics.

Mike

[DMcMahon]

Thank you Mike for the detailed reply. You have not painted a rosy picture of the Mk. 6 Deck, that is good to know.

David

[Ted Kendall]

The Mk6 wasn't vastly different from the Soundmaster of fifteen years earlier. In the same time, Revox went from the T26 to the A77. When it was launched, it was described as representatve if the sort of recorders which would be seen seven or eight years hence. By 1975, the Japanese were making decks which superficially resembled the A77 and exceeded it in perceived value, but none of them grasped the nettle of a direct drive capstan and modular, easily aligned electronics.

[barrymagrec]

Quite. The sad story of Brenell and Ferrograph is that while Revox moved from a solid basic tape machine to something sophisticated and state of the art (A77) they changed the paint colour and the shape of the meter.

[Boulevardier]

Originally Posted by barrymagrec

Quite. The sad story of Brenell and Ferrograph is that while Revox moved from a solid basic tape machine to something sophisticated and state of the art (A77) they changed the paint colour and the shape of the meter.

I think you sum it up beautifully Barry! When I ordered mine (pre-internet days, so no easily available specs) I was expecting something at least vaguely state-of-the-art and meeting the contemporary standards. Instead, I got the traditional Mk 5 with minor cosmetic tarting-up to make it (just about) look contemporary. And the large-spool, high-speed mods were just a joke! Mind you, no real alternative to it by 1970s.

Mike

[Ted Kendall]

No, none. Truvox, Magnavox and BSR had shut up shop, Scopetronics were trying to sell a ten-year-old design to the BBC (with pressure pins, yet!) and Ferrograph weren't selling Series 7 decks (a transistor Vortexion was advertised but never produced), so that left Brenell as the only source of new transports. The Type 19 was a better proposition, granted, but that was priced above Revox territory anyway.

[terry123]

"Vortexion was advertised but never produced" Not quite Ted, a handful escaped the factory. Sid Brown and George Ferriman could not get the all transistor design to work satisfactorly and abandoned it. Here is a mono one that escaped ! ex BBC by all accounts.

regards
Terry

[DMcMahon]

That photo is interesting, looks like a Ferrograph Series 7 control chassis with Vortexion amplifier/control panel.

David

[Plus4db]

Yes it's a Ferrograph Series 7 Mk1 transport. Very interesting thread gents! I've been looking a lot recently at The Ferrograph Series 7s, despite their shortcomings there's something I like about them, with some great features. But Lord oh Lord, pressure pads and no tape lifters in the 70s, it's a wonder any heads for them have survived!

I suppose it made sense, with the one innovative feature of this transport - the 'shuttle' wind/rewind, which would have been very useful for transcription/editing and logging at the BBC and other semi-pro use. I realise too that Ferrograph were fast running out of any development budget but why oh why did they not incorporate simple manual lifters with the pressure release lever? I have seen at least one on ebay where someone added a roller above the tape counter for out of headblock rewind.

[barrymagrec]

Originally Posted by DMcMahon

That photo is interesting, looks like a Ferrograph Series 7 control chassis with Vortexion amplifier/control panel.

David

I`ve seen that picture before and I always assumed that at least a few were built, however my brother worked at Vortexion briefly in 1973 and nothing was happening on tape machines at that time.

[DMcMahon]

Originally Posted by terry123

"Vortexion was advertised but never produced" Not quite Ted, a handful escaped the factory. Sid Brown and George Ferriman could not get the all transistor design to work satisfactorly and abandoned it. Here is a mono one that escaped ! ex BBC by all accounts.

regards
Terry

The "A guide to British tape recorders" book references the mono version as model WVB7L-T and the stereo version as model CBL/7T.

David

[Ted Kendall]

The one and only advert I've ever seen for the CBL7 was in the Tape Recording Yearbook. It's easy enough to make a dummy for a photo.

[barrymagrec]

How true. I cite the cover of Tape Recorder magazine (later Studio Sound) December 1968.

https://worldradiohistory.com/Archiv...udio-Sound.htm