Hacker GP42 - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

crackle · 5th Apr 2020, 8:04 pm

Have you checked the tracking pressure is correct for the cartridge. This can make quite a difference.
Mike

Viscount · 5th Apr 2020, 8:19 pm

Quote:

Originally Posted by vidjoman

Maybe try a little piezoelectric unit. No crossover needed, just connect to the speaker terminals. See how it sounds and if better then mount it on the back of the speaker grill.

must admit i hadnt considered a piezo unit but its worth a try i suppose

Viscount · 7th Apr 2020, 5:54 pm

Quote:

Originally Posted by Edward Huggins

I contributed in 2019 to the thread linked to in Post #5. I can never understand why Hacker (given their undoubted expertise) never specified a 10" x 6" twin-coned unit in the GP42. I agree with all of the comments about a general lack of treble and I compensate by listening to mine on-axis. This does make a real difference.

A non-invasive fix would be wire a 3" cone tweeter (+ 2.2uf filter cap) mounted in a small enclosure and place it near to the cabinet. Years ago Grundig made omnidirectional, add-on, Tweeters. These were very effective and could be copied for a very low cost.

OK so just tried a temp tweeter stood alongside the hacker (2.2uf cap fitted) the difference is incredible, so will make an enclosure at some time, well worth the effort.

John10b · 8th Apr 2020, 9:20 am

Interesting comment from Vidjoman #20, regarding turning down the treble control. I shall always remember going to my first Opera. I thought the violins and brass sounded so “tinny “. This was because I was used to listening to my AM radio, which had no top!
John

Viscount · 8th Apr 2020, 3:50 pm

Well I've made the enclosure and fitted an oblong horn tweeter. Need to finish the cabinet, will post a pic when it's completed.

Viscount · 9th Apr 2020, 5:18 pm

Pictures of the complete unit. Front grill is from a Hacker Herald, reconnection block is from an old speaker cabinet. Colour is light grey

Edward Huggins · 9th Apr 2020, 6:07 pm

Wow, that's impressive! What type/make of Horn Driver are you using?

Viscount · 9th Apr 2020, 8:04 pm

well the horn tweeter came out of an old AUNA cabinet the whole thing was rated at 200 watts , horn size 200X80 mm, many thanks for the nice comment

Viscount · 11th Apr 2020, 10:59 am

mods please close

5th Apr 2020, 8:04 pm	#21
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	Re: Hacker GP42 Have you checked the tracking pressure is correct for the cartridge. This can make quite a difference. Mike

8th Apr 2020, 9:20 am	#24
John10b Nonode Join Date: Nov 2016 Location: Aberaeron, Ceredigion, Wales, UK. Posts: 2,882	Re: Hacker GP42 Interesting comment from Vidjoman #20, regarding turning down the treble control. I shall always remember going to my first Opera. I thought the violins and brass sounded so “tinny “. This was because I was used to listening to my AM radio, which had no top! John

8th Apr 2020, 3:50 pm	#25
Viscount Heptode Join Date: Jan 2018 Location: Folkestone, Kent, UK. Posts: 711	Re: Hacker GP42 Well I've made the enclosure and fitted an oblong horn tweeter. Need to finish the cabinet, will post a pic when it's completed.

9th Apr 2020, 5:18 pm	#26
Viscount Heptode Join Date: Jan 2018 Location: Folkestone, Kent, UK. Posts: 711	Re: Hacker GP42 Pictures of the complete unit. Front grill is from a Hacker Herald, reconnection block is from an old speaker cabinet. Colour is light grey Attached Thumbnails

9th Apr 2020, 6:07 pm	#27
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,326	Re: Hacker GP42 Wow, that's impressive! What type/make of Horn Driver are you using? __________________ Edward.

9th Apr 2020, 8:04 pm	#28
Viscount Heptode Join Date: Jan 2018 Location: Folkestone, Kent, UK. Posts: 711	Re: Hacker GP42 well the horn tweeter came out of an old AUNA cabinet the whole thing was rated at 200 watts , horn size 200X80 mm, many thanks for the nice comment

11th Apr 2020, 10:59 am	#29
Viscount Heptode Join Date: Jan 2018 Location: Folkestone, Kent, UK. Posts: 711	Re: Hacker GP42 mods please close