Bush SRP30C record player, electrostatic tweeter. - UK Vintage Radio Repair and Restoration Discussion Forum

MurphyNut · 30th Nov 2019, 6:14 pm

I've made very good progress on the said record player and everything works as it should and I'm impressed with the sound.
The only problem left now is that the square Grundig electrostatic tweeter is completely silent.
This seems to be a common problem, I was wondering what others have done. As the player is sounding so good is it really worth doing anything, or am I missing even better sound if it was repaired or replaced with something else?

slidertogrid · 30th Nov 2019, 7:10 pm

I have seen these tweeters reconditioned with new foam but I prefer to replace them with a modern tweeter. I wire the modern unit across the main speaker with a capacitor in series removing the wires to the original tweeter.
The space is limited though if you use a tweeter that is too deep it will foul the valves when the front is refitted.
I am not sure if there is much improvement though to be honest these players don't seem to have masses of treble.
Rich

leslie5555 · 30th Nov 2019, 7:46 pm

I have repaired a few of these it's an easy thing to do, but the results have been minimal and not really worth doing, in my opinion.

Edward Huggins · 1st Dec 2019, 12:07 am

I agree with all of the above. If needed, a 3" 3-5 ohm paper cone tweeter with a 2.2uf non-polarised cap (an ALCAP at c.0.90p) would be an adequate replacement wired from the OPTX secondary. Ensure the previous tweeter connections are isolated.

Ekcoman · 1st Dec 2019, 9:18 am

There was an excellent little video on You Tube but cant locate. Quite honestly after restoring a good number over the years you'd be hard pressed to notice a difference once done. Not worth the effort in my opinion.

MurphyNut · 3rd Dec 2019, 3:25 am

Thanks for the replies, it certainly sounds like there is no major loss to the sound quality with the electrostatic tweeter not working. I shall leave it be.

simpsons · 3rd Dec 2019, 6:42 pm

I have one of these record players and the tweeeter works.

The electrostatic tweeter not only adds to the high frequency reproduction of the record player, from around 1kHz to 20kHz but, in addition, adds to the soundstage.

This makes the reproduced sound seem to come from across the front of the player rather than a single point.

Should the original 1950's GC8 cartridge be fitted then the tweeter was really necessary as after 1kHz, from published data, the cartridge output literally fell off the shelf and that extra top made a lot of difference.

Should a BSR SC12M or similar be installed then according to other members, the frequency response was much better but there are no graphs to show where the +- 3dB response between 15Hz to 20kHz falls.

From what is available on Google, it seems repairing the tweeter is not beyond the wit of man but of course it always seems easy when someone else does it!

Chris

30th Nov 2019, 6:14 pm	#1
MurphyNut Heptode Join Date: Apr 2016 Location: Croxley Green, Hertfordshire, UK. Posts: 979	Bush SRP30C record player, electrostatic tweeter. I've made very good progress on the said record player and everything works as it should and I'm impressed with the sound. The only problem left now is that the square Grundig electrostatic tweeter is completely silent. This seems to be a common problem, I was wondering what others have done. As the player is sounding so good is it really worth doing anything, or am I missing even better sound if it was repaired or replaced with something else? __________________ Clive

30th Nov 2019, 7:10 pm	#2
slidertogrid Octode Join Date: Apr 2005 Location: Peterborough, Cambridgeshire, UK. Posts: 1,898	Re: Bush SRP30C record player, electrostatic tweeter. I have seen these tweeters reconditioned with new foam but I prefer to replace them with a modern tweeter. I wire the modern unit across the main speaker with a capacitor in series removing the wires to the original tweeter. The space is limited though if you use a tweeter that is too deep it will foul the valves when the front is refitted. I am not sure if there is much improvement though to be honest these players don't seem to have masses of treble. Rich

30th Nov 2019, 7:46 pm	#3
leslie5555 Heptode Join Date: May 2015 Location: Reading, Berkshire, UK. Posts: 692	Re: Bush SRP30C record player, electrostatic tweeter. I have repaired a few of these it's an easy thing to do, but the results have been minimal and not really worth doing, in my opinion.

1st Dec 2019, 12:07 am	#4
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,338	Re: Bush SRP30C record player, electrostatic tweeter. I agree with all of the above. If needed, a 3" 3-5 ohm paper cone tweeter with a 2.2uf non-polarised cap (an ALCAP at c.0.90p) would be an adequate replacement wired from the OPTX secondary. Ensure the previous tweeter connections are isolated. __________________ Edward.

1st Dec 2019, 9:18 am	#5
Ekcoman Heptode Join Date: Jan 2008 Location: Southend, Essex, UK Posts: 663	Re: Bush SRP30C record player, electrostatic tweeter. There was an excellent little video on You Tube but cant locate. Quite honestly after restoring a good number over the years you'd be hard pressed to notice a difference once done. Not worth the effort in my opinion. __________________ "I really am seriously downsizing "

3rd Dec 2019, 3:25 am	#6
MurphyNut Heptode Join Date: Apr 2016 Location: Croxley Green, Hertfordshire, UK. Posts: 979	Re: Bush SRP30C record player, electrostatic tweeter. Thanks for the replies, it certainly sounds like there is no major loss to the sound quality with the electrostatic tweeter not working. I shall leave it be. __________________ Clive

3rd Dec 2019, 6:42 pm	#7
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Re: Bush SRP30C record player, electrostatic tweeter. I have one of these record players and the tweeeter works. The electrostatic tweeter not only adds to the high frequency reproduction of the record player, from around 1kHz to 20kHz but, in addition, adds to the soundstage. This makes the reproduced sound seem to come from across the front of the player rather than a single point. Should the original 1950's GC8 cartridge be fitted then the tweeter was really necessary as after 1kHz, from published data, the cartridge output literally fell off the shelf and that extra top made a lot of difference. Should a BSR SC12M or similar be installed then according to other members, the frequency response was much better but there are no graphs to show where the +- 3dB response between 15Hz to 20kHz falls. From what is available on Google, it seems repairing the tweeter is not beyond the wit of man but of course it always seems easy when someone else does it! Chris