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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
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21st Oct 2020, 7:53 pm | #1 |
Diode
Join Date: Oct 2020
Location: Buckingham, Buckinghamshire, UK.
Posts: 3
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Replacement Speakers. HMV 2032.
Hi all,
Very new - restoring an HNV 3012 unit with a Garrard 3000 deck. Up to the point of needing new speakers - currently has 2 mid and 2 tweeters, two are shot and the other two sound well past their date (21 Nov 1967!). Looking for advice on what to replace them with - want them to fit inside the case and look original. Old amp was totally shot and beyond my skills to repair so have opted to go for a modern 50w amp with a separate pre-amp. My next challenge is controlling the amp controls with the original pots, but that's another day! Any guidance is most welcomed. Thanks |
21st Oct 2020, 8:08 pm | #2 |
Hexode
Join Date: Jan 2013
Location: Wigan, Lancashire, UK.
Posts: 372
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Re: Replacement Speakers
Hi,
I have not found any pictures of an HMV 3012 on the web. Could you take some photos of yours including ones of the original amplifier and speakers? |
21st Oct 2020, 11:45 pm | #3 |
Octode
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,483
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Re: Replacement Speakers
Should your unit be from the HMV Stereomaster range, then it is likely to use long throw bass/mid range speakers together with a front mounted tweeter.
These are mounted in a sealed enclosure although I don't remember seeing any accoustic damping which is really necessary. For my money, you will need to replace them, if faulty, with a similar spec to get a decent sound as they were chosen to do just that. But beware, the Garrard 3000 turntable cartridge is no longer available and whilst mods are available to use others, they are not easy mods. This might mean, at some time, fitting a different, some might say, improved Garrard deck. As mentioned, let's have some pics and speaker dimensions. Good luck with the project Chris |
22nd Oct 2020, 10:38 am | #4 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Replacement Speakers
It sounds like you will be gutting the HMV. If you are fitting a 50W stereo amp you will need speakers that can handle that kind of power as the original amp was rated at just 7 watts per channel. These HMVs used 6.5" Bass/Mids and 3.5" Coned Tweeters. You will be unlikely to find suitable coned tweeters now, so they will need to be Domed units. There then remains to decide what type of Crossovers you will need for the new drive units which can range from very simple to quite complex. If you are putting all kind of power into a rather small sealed box, you may then to consider the affect this will have on the Garrard 3000 autochager in terms of acoustic feedback. This then leads to considering the best form of effective internal damping. Finally, there is the questing of matching the existing cartridge into a modern stereo amplifier which is unlikely to have a high-impedence input. In short,"upgrading" a vintage unit like this is not going to be a straightforward as you may think - and you may end up with an expensive but highly compromised unit!
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Edward. |
22nd Oct 2020, 10:41 pm | #5 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,801
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Re: Replacement Speakers
If that's an early transistor stereogram, it's likely that the speaker impedance is quite high, so a modern 50W amp intended for 8 Ohms load won't be able to get anywhere near its full power before clipping. I seem to remember some ex radiogram speakers were more like 35 ohms.
But as the originals are shot, then their suitability for any amplifier is nil. I've seen one 'upgraded' radiogram where the speaker spaces were big enough, and someone had opened up the holes in the ply behind the fret and butted a Wharfedale diamond up to it. Sounded quite good. David
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23rd Oct 2020, 9:18 am | #6 |
Octode
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,483
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Re: Replacement Speakers
Thanks Radio Wrangler for causing me to think about using long throw speakers and so on. It seems that should the gram in question use 6.5" loudspeakers, they are not long throw but bog standard with a foam surround.
They would also be 10 ohms which sounds a bit odd but that's how you get around the engineering limitations of small heatsinks. Long throw speakers in a thorn? I'm sure I've seen them but time needs to be invested in other matters. Chris |
23rd Oct 2020, 9:42 am | #7 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,801
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Re: Replacement Speakers
You can also find some small but potent speakers in the car accessory market, but it's a case of looking around to find something decent without high prices. Scrap yards nowadays just want to sell you the entire door.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done |
26th Oct 2020, 10:49 pm | #8 |
Diode
Join Date: Oct 2020
Location: Buckingham, Buckinghamshire, UK.
Posts: 3
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Re: Replacement Speakers
Sorry all - been super busy with work, really appreciate the replies - some pics for you are attached.
There is a date stamp of 21 November 1967 (the day before my late Mothers 23rd Birthday). The model is a 2032, apologies for the earlier mistake. |
27th Oct 2020, 8:39 am | #9 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Replacement Speakers
Thanks for clarifying the Model number as I could not search out the one you cited. There are a number of high-power handling 6.5" bass/mid driver units to choose from. These will be 8 ohm units. The 3" tweeters can be replaced with Domed units.
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Edward. |
28th Oct 2020, 10:46 pm | #10 |
Diode
Join Date: Oct 2020
Location: Buckingham, Buckinghamshire, UK.
Posts: 3
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Re: Replacement Speakers. HMV 2032.
Think I'll look into car speakers that fit and go with bass/mids and separate tweeters on a crossover network. Been a number of years (decades!) since I've done this stuff. No hurry.
Have got a sample of stain which I'll test on a plank of wood and then apply to a small section inside where it'll never be seen. Going for Dark Oak initially and will see if this is too dark. I fear the lighter shades might be too light, but a few test patches first. Much, much more sanding is needed. Does anyone have any opinion on varnish - either matte, satin or gloss? I'm thinking satin at the moment.. |
30th Oct 2020, 8:43 am | #11 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Replacement Speakers. HMV 2032.
Satin would be ideal. Remember car speakers are usually rated at 4 ohm, whereas you really need 8 ohm.
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Edward. |
30th Oct 2020, 1:58 pm | #12 |
Heptode
Join Date: Mar 2014
Location: Leeds, West Yorkshire, UK.
Posts: 899
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Re: Replacement Speakers. HMV 2032.
If you want it to look as it did when it was new give it a good scrub with hot soapy water and a brillo pad .This removes years of old polish and dirt .Then a light sand with some fine sandpaper and then apply teak oil with a bit of rag not a brus.h the oil will soak in covering any light scratches .Be very careful when sanding as the teak veneer is quite thin .I would not go near it with any kind of stain .All that will do is make it look like something its not and once its on its impossible to get off
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