"Loud Enough to fill a Small Hall"

[Edward Huggins]

I wonder how may of you will remember this claim when applied to the promotional materials for the then newly introduced portable record players of the mid-1950s?

There was a growing market at that time for more powerful portable players for use in Schools, Dance Studios, Public Tea Dances, Village Halls as well as for Domestic use.

However, when we come to analyze "loud", this probably meant, at best, a 2 stage amplifier, (probably with a 6V6 output) driving a 6.5" round speaker and giving around 3 watts at full pelt....

Yet, in a small hall, and stacked with highly modulated Joe Loss 78s, they did indeed sound loud enough for their purpose.

All of this seems (innocently) so far removed from the 50-100 watt systems we were so swamped with in later years. Yet, to my memory at least, and in those old dingy everberent halls, it still sounded pretty loud enough to me!

[Vintage Engr]

They were indeed loud Edward!.

I well remember various advertisements in both Practical Wireless & also Wireless World, from a plethora of suppliers of both kit and ready-built audio amplifiers, all stating 'Loud enough to fill a small hall" (Define 'small-hall'),

We had a Linear Conchord in our Church hall, with some Wharfedale speakers mounted on fairy crude baffles, and it was a large hall. There was more than enough output.

But then, the speakers were efficient, and were being driven by 'real' watts, as in watts RMS....

I do a lot of local P.A around our local villages here, and using a mix of old & new kit. Some of the old stuff produces ample output, but I can blast out the power if need be, -not very often required.

David.

[Andrew2]

I too recall those ads. Other suitably-vague phrases were 'from a whisper to a roar' and 'room-filling volume'.

[G6Tanuki]

A well-designed single-ended 6V6 amp will give you a bit over 5 Watts of audio. Coupled to an 'efficient' speaker in a suitable box the result can be satisfyingly-loud.

[Currently listening to Dusty Springfield's "Just don't know what to do with myself" via a single-ended 6BW6 amp - the successor-valve to the 6V6 - and I don't need to turn it up to eleven]

[AndiiT]

Hi, some time ago I procured a Bush SRP31C which had very low volume (I of course now know that this was due to low HT as the result of a faulty rectifier)
Upon asking one of my, now retired, colleagues who had been in the same trade as myself however more predominantly in the valve days than I, he said that the sound from a record player such as my Bush should be "Loud enough to fill a small hall"!!

At a rough guess I would say that he was of a similar generation to Edward so perhaps recalls the promotional material mentioned in this thread.

Regards

Andrew

[emeritus]

In the 1970's I used to provide the music for the social club I belonged to, using a cassette recorder playing via the amplifier of a Ford (Plessey) car radio into a pre-war 10" 3Ω speaker that dad had reclaimed form an old radio. The radio's amp was, I think, rated at 1W and provided more than enough volume for our hall. I had made a 12V + 7.5V supply for the radio and recorder, and could run it from an external 12V battery pack of blue U2 cells for things like beach barbecues. Older speakers are usually much more acoustically efficient than modern offerings.

[Herald1360]

Originally Posted by Vintage Engr

But then, the speakers were efficient, and were being driven by 'real' watts, as in watts RMS....

Real watts are not watts RMS, though they are volts (rms) * amps (rms) which gives the average power if the load is resistive.

Watts RMS was just another term coined to try to get round all the various claims about power output from "hifi" amps in the early transistor period.

See here: https://vintage-radio.net/forum/showthread.php?t=7054

(And many other threads in a similar vein).

[Hartley118]

ISTR that my RSC A10 30W amplifier which I put together in 1961 was advertised as suitable for large halls and Garrison Theatres. Its pair of 807s certainly packed a punch into a pair of 12-inch Plessey speakers at college musical performances. Increasing the volume control just made it louder and louder!

But then the requirement was to be heard rather than deafened.

Martin

[GrimJosef]

Our hearing is, approximately at least, logarithmic. And a 100W amplifier is 'only' 13dB louder than a 5W one. 13dB is quite a bit, but not the difference between a whisper and a shout.

Cheers,

GJ

[G6Tanuki]

Originally Posted by Hartley118

ISTR that my RSC A10 30W amplifier which I put together in 1961 was advertised as suitable for large halls and Garrison Theatres. Its pair of 807s certainly packed a punch into a pair of 12-inch Plessey speakers at college musical performances.

In times-past as a student amp-builder I was happy to get 120W from a pair of 807s in zero-bias class-B. My customers were happy too. When your lead-guitar does the solo from Layla and you see a sustained 300mA on the anode-current meter you know you're having fun. Replacement 807s were cheap in the late-70s.

[kevinaston1]

A few years back, I was speaking to a London musical instrument retailer, and congratulating him on selling two high powered PA systems in one week. Yes he said, they were bought by a chap who loves his reggae; he has them set up at home.

Said PA system was 12 self powered cabinets blasting out 7200 watts. I wonder if he has any neighbours (or hearing).

Kevin

[Terry_VK5TM]

Just on the off-chance, I had a look to see if there was any definition or recommendation as to what a "small hall" was and found this https://www.sportengland.org/media/4...nity-halls.pdf

Small hall
Supplementing the main hall with a restricted range of use. For sports, 9 x 9m or preferably 10 x 10 x 3.5m high is recommended...

Obviously modern, but I wonder if it had any basis relating to the earlier era the OP is describing?

[suebutcher]

Originally Posted by GrimJosef

Our hearing is, approximately at least, logarithmic. And a 100W amplifier is 'only' 13dB louder than a 5W one. 13dB is quite a bit, but not the difference between a whisper and a shout.

If I remember correctly, to the human ear 13dB is "twice and a bit" as loud as 0dB.

[Craig Sawyers]

Our school had two record players. One was in the music department, and the teacher used to play us pieces of music on that, to a class of around 30. I don't recall it being quiet! I remember Britten's "A Young Person's Guide to the Orchestra" and Mozart 40.

There was another one that other teachers could use. Our English teacher borrowed it to play plays by Shakespeare (I definitely recall Henry V, with Paul Schofield). Again no recollection of quiet.

These definitely left an impression on me, 50 years ago. Still listen to a wide range of music, and a real Theatre buff (even yesterday, A Day in the Death of Joe Egg in London).

In praise of the old record players!

Craig

[wd40addict]

A similar thing happened with adverts for portable 16mm projectors where they would talk of a particular machine as being suitable for audiences of n 100. How was this possible?

Well the typical 12" 16mm speaker has a frequency response with a peaky midrange to help with speech clarity. The portable machines were designed to give film shows in halls to hundreds of people using what we would now regard as tiny amplifiers (10-15W). But, with an efficient peaky speaker it worked!

Regarding record players I was once given the job at my primary school of playing records for the end of term 'disco'. It was the middle seventies, but the equipment was older and consisted of a solid schools type record player. It was probably a Goodsell or Comber in a wooden box which sat on a trolley with a large open baffle speaker. Was it Hi-fi? no. Was it deafening? no. Was it adequate for the job in hand? Yes.

It must've been a valve unit as I remember the control panel got pretty hot after an hour!

[vidjoman]

In the early 1950's I went to see the projectors in our local cinema which seated about 1400 people in the stalls and upstairs balcony. The sound system was 2 x 10 watt amplifiers, of which 1 was in use and the other was on standby. They were used alternately during the week so each had the same usage. The speakers were under the stage and were 2 x 8 inch drivers attached to separate long horns that had an opening at the front edge of the stage and about 3 feet across. The sound level was good and the sound from the films was easy to hear. I don't know if the Compton organ which rose majestically up from the pit used the same speakers - I doubt that it did and probably had it's own built-in speakers.
When there were 'pop' music shows they added extra speakers and amplifiers in the auditorium, but I don't know what they were.

[raditechman]

In the 1960's I worked at a large 1500 seats in circle and stalls cinema. The amplifier was rated at 30 watts. Although it used 4 gently run KT66's and they lasted for years! Efficient horn speakers, the fader (volume control) was never more than quarter up even with a full house.
The monitor amp for the projection box speakers was a singled ended 6V6 amp, and no trouble hearing the sound above the projector noise.
We had four sets of main amplifiers as occasionally we would get a film with 4 track stereo sound.
The organ of course worked with air blowing through pipes!
3 to 5 watts used to be plenty.
Now speakers are not so efficient and it seems people like the sound not just to be heard but to vibrate the bones in their bodies too, so 100 watt and more amplifiers get used.
I think the Empire cinema in Leicester Square now has 87 JBL speakers and 85kW of amplification- you have been warned!
John

[vidjoman]

It was always nice and warm in the projection room due to the carbon arc lamps of the projectors. I think the amps and projectors in my cinema were installed when it was built - 1930's I think. I went there during the war as a young child to watch films and remember seeing a giant searchlight in the car park spotting planes.

[MurphyNut]

What people considered loud in the 1950's would be deemed quite modest now.
Saying that I'm often appalled at the over-loud and poor quality sound coming from systems used at functions these days.
Despite all this power and technology they often sound horrible and you go home with a headache......Bring back the 1950's Dansette!

['LIVEWIRE?']

I'm inclined to agree with you, Clive. Maybe a little more power and fidelity that some of the fifties kit could provide is desirable, but hundreds of watts is, IMHO, ridiculous, even in a large hall, never mind in home or car stereos.