History - The Hi-Fi Section

As a young lad of about 12 years old, my parents brought me a second-hand "Fidelity" record player. A typical model from the early 1960's, consisting of a small 7" turntable with a valve amplifier etc, fitted into a small carrying case. After a year or so the unit no longer worked. The amplifier had failed, but the turntable still worked. So I experimented by fitting a cheap Ronette 105 stereo crystal cartridge into the arm. The later purchased from "Radiomatics" of St.Benedicts Street in Norwich (The shop originally started in Oak Street). The gentleman who ran "Radiomatics" was always most helpful and obliging, alas I never got to know his name. So ..... feeding the cartridge output directly into a pair of homemade headphones. The later based around a pair of GPO type 4T receivers (approx' 20 ohms DC) as used in 700 series telephones, mounted in homemade fiberglass ear-cups/headphones. Well, as you would expect, the sound quality was absolutely awful and very quiet, but ..... , and this was the important part, it was the first time I had ever listened to a stereo record and something that I shall never forget.

Ronette 105 cartridge

Around the same time, I was given an old Collaro turntable, from a family member, Arthur Shopland. The unit required a little repair work, but it was soon up and running, alas without any of the dreaded auto-changer facilities. The Collaro turntable was mounted in a suitable homemade plinth and utilized the existing Acos GP91-1, mono crystal cartridge (for some reason, I never thought of using the Ronette 105 sterreo cartridge, wired in mono - Oh well). The output from the GP91 cartridge was then connected to "Gram" input of my fathers pride and joy, an old "Sobell" valve radio receiver, type 615. This being purchased by my father in 1948. The Sobell was a wonderful old radio, with excellent Short wave coverage. The output stage is based around one of the famous 6V6 type valves, together with a somewhat small output matching transformer ..... I thought my records sounded wonderful.

My fathers Sobell receiver type 615

The association between Hi-Fi and Sound Recording, goes "Hand in Hand". This is clearly illustrated by the front cover of an old "Hi-Fi News", dated September 1966.

Note the classic "Telefunken" valve mic'..... close-up !

The Armstrong 521 pre/power amplifier, together with the Armstrong 524 FM tuner, sounded fine, but the amplifier was forever "Blowing" the 2 Amp HT fuses, together with "Taking out" the AL102 Output transistors. On a sustained Bass line, the "Pilot" lamp would start to flicker ..... and the next minute, "Pop". Maybe, most definitely, I was expecting too much from the unit ..... however, I always thought that fuses were fitted to help protect the venerable components in equipment. Sadly, in the case of the Armstrong 521, this was obviously not so. The AL102 "Output" transistors were "Germanium", 30 Watt TO3 types, capable of handling 6 Amps, in theory ..... I eventually replaced all four of the AL102 "Output" transistors with the excellent "Mullard" OC28 transistors, and never had anymore problems. Maybe the "Odd" fuse would blow now and then, but that was it.

The Armstrong 521 was an excellent amplifier. However, due to the amount of "Auxiliary" equipment being used, I was soon to run out of "Input Sockets". I felt that it was time for a change, with the Armstrong 521 and 524 units, being sold to two of my fellow BT colleges. My latest system would be centered around equipment from the "Pioneer" range. Namely that of the SA-8100 Stereo Amplifier and their "Flagship" TX-9100 Stereo Tuner. I would also have liked the "Matching" Pioneer CTF-7171 cassette deck, but this was out of my budget at this time. The sensitivity and selectivity of the Pioneer TX-9100's FM section, was absolutely wonderful, but I fear that the sound quality of the Armstrong 524 FM tuner, with M8 stereo decoder, was far superior. The sound of the Armstrong 521 Amplifier, also had something that the Pioneer SA-8100 lacked. Both of the "Pioneer" units are still in regular use to-day (2007), despite many "Blown" panel and meter lamps on the TX-9100 tuner.

Eventually I found a second-hand CTF-7171 cassette deck, in the late 1980's, to complete my set-up

The turntable then in use, still being a Goldring-Lenco GL75/P, with a history of different cartridges. Ranging from the "Goldring" G800E, through to the ever popular "Shure" M75ED. In 1976, the "Lenco" L75 arm was removed, and after some modification to the GL75 metalwork, I fitted the ever popular SME 3009 mkII pick-up arm. Together with a Shure V15/III moving magnet cartridge. This was much better !

Within a few months, I purchased a second-hand "Garrard" 401 transcription unit, fitted with a SME 3009 pick-up arm. I utilized my Shure V15/III cartridge (from the modified GL75) with the 401/SME combination.

Compared to my GL75/SME/V15 combination, there was a loss of something. What, I could not say, but something seemed to have been lost in the change. I tried various cartridges in the Garrard 401/SME 3009 combination, but I was never really that happy with the results.

As impressed, and satisfied, as I was with the homemade transmission line loudspeakers .....  I was to be introduced to some large "Tannoy" loudspeakers. Well, that was something else. Maybe not so clean as the transmission line loudspeakers, but these Tannoy "Arden's" were absolutely enchanting. It was not too long before I built a pair of these monsters. A ported cabinet design, based around the Tannoy HPD385 15" dual concentric drive unit. Once the cabinets were constructed and the drive units fitted (prior to finishing off the cabinets cosmetically) they were brought in, from the workshop, for listing tests. Sadly, I liked the sound so much, that the loudspeakers never got taken back to the workshop for veneering or having the grill cloths fitted.

I recall a friend, Mike Green, calling round to have a listen to the DIY Arden's, and his wife, Valerie, saying that the DIY Arden's looked more like two large washing machines, rather then loudspeakers !

The DIY Tannoy "Arden's" were fine loudspeakers, but as time went by, I wanted a cleaner bass response. Currently, the Tannoy arden's were free standing in alcoves, either side of the fireplace. Now .... if I utilized the wall's of the alcoves, then I could build some unobtrusive, yet large and solid enclosures. The internal volume of the enclosures would be 2-3 times greater then that of the original "Arden" design, thus offering greater bass extension. I would utilize the solid concrete floor, for the base of the enclosure, with the sides and back, being the existing walls around the alcove. A new, short wall, would be required for the front of the enclosure, constructed from "Solid" concrete building blocks. The baffle board, for the loudspeaker assembly, was cast in concrete, reinforced with a steel mesh. As the drive units were quite close to the floor, the concrete baffle boards were mounted at an angle, to help project the sound upwards i.e. to arrive at ear level in the listing position. The top of the enclosure, would be constructed from paving slabs, covered with "Veneered" chipboard shelving on the top. These enclosures worked very well indeed and looked quite unobtrusive in the listing room.

One of the many things that I missed, when moving to Leicestershire, was not being able to take the "Alcove" enclosures with me !

Tannoy HPD385 drive unit, in "Alcove" enclosure

So it's back to turntables ..... The "Modified" GL75/SME 3009 mkII was an excellent turntable, but I fancied the idea of a "Unipivot" arm.

In 1979, both myself and a college from BT, namely Tony Milk of BMX fame, each constructed a "Unipivot" arm from a design published in the July 1968 issue of Hi-Fi News. Incorporating our own "Minimalist" design changes and requirements. We machined the required parts using Tony's excellent, back garden, workshop facilities. Both his time, and use of machinery, being very much appreciated.

Tony combined his "Unipivot" arm with a Decca London cartridge and Garrard 301 turntable. 

I fitted my "Unipivot" arm, complete with Shure V15/III cartridge, onto the "Modified" GL75, in place of the SME 3009. A sonic improvement was immediately noticed. However, the turntable/arm coupling was far from ideal, and when you consider how minutely small the information on the record is, it makes sense not to have any "Slack" in the system. Ideally, from the stylus tip, back through the whole system of arm/plinth/bearing/turntable to the record surface, there should be no "Slack/Free-Play" call it what you will. 

DIY "Unipivot" arm featuring a strong, yet

lightweight, copper clad fibre-glass (PCB) cartridge carrier

So, to the second modification ..... I removed the GL75 turntable from the original plinth, and set to cut away as much metalwork as possible. Leaving just the bearing and motor/idler wheel assembly behind. The base of the bearing assembly being rigidly supported to the metal base plate via three metal braces. Therefore not allowing the turntable platter to rock in any plain. This was then "Securely" re-fitted to a solid 3" (75mm) thick "High Density" Chipboard, Sandwiched, plinth. Together with the homemade unipivot arm. I had a 3/8" (10mm) thick "Glass" platter made, and I constructed a heavy "Balanced" weight, for clamping the record to the platter. The new modifications helping to make a "Rigid" coupling between the record, turntable, arm and Shure V15/III cartridge.

The combination worked wonderfully well, and looked quite stylish for the time (Circa 1979).

After this modification, the quality and feel of the sound, improved greatly. The tempo of the music came across with more feeling and emotion. You just had to tap your feet.

Alas, from a DIY view point, this was about the best sound quality that I could extract from my V15/III in this combination ..... or was it ?

GL75 motor/turntable & "Unipivot" arm / Shure V15/III

(Controls recessed under the front edge of the plinth)

Construction of "Floating Sub-Chassis" - Circa 1979

Technics SL150 and SME3012 - Circa 1980