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View Full Version : A curious thing has happened--sequel!!


tyke
10-12-2019, 10:29
Many thanks for everyone's' replies to my enquiry about sudden appearance of hum following bi-wiring my Myryad MA120 amp to my Kef Reference Series Model 2 speakers.
When I was routing the second pair of speaker cables to the amp I accidentally pulled one of the inputs to the phono preamp. The preamp jumped off the rack, hit me on the bridge of the nose and landed, belly up, on the shag pile! I replaced it on the rack and only just managed to stop the blood dripping from the end of my nose onto the pale cream carpet.
Yesterday I reverted back to single cables to the speakers, replaced the links removed earlier and switched on the amp. To my dismay the hum remained.
I pondered that the only other change that had happened was the phono preamp's excursion onto the carpet. In desperation I turned off the power supply to the phono stage and the hum disappeared.
I checked all the connections to the phono preamp, particularly the ground connection, but the hum remained when I turned on the power amp.
In view of this, I am now looking for a simple, no nonsense, phono preamp. The current one is a HiQ, supplied by Nigel at Chantry Audio when he serviced my Ariston RD11S turntable in 2004.
Sorry to be long-winded but thought this might amuse some of you. Fortunately, I can laugh about it now.
Any suggestions or recommendations about a phono preamp would be gratefully received.
Ali Tait
10-12-2019, 10:59
Budget?
Firebottle
10-12-2019, 11:13
I could take a look at your current phono if you like?
tyke
10-12-2019, 11:31
Budget?

Good question!! I paid £149.00 for the HiQ in 2004, so would imagine I would have to spend this amount today, pension permitting.
I would be reluctant to spend more than this, as I only listen to vinyl occasionally.
tyke
10-12-2019, 11:32
I could take a look at your current phono if you like?

My main concern would be would it be cost effective, bearing in mind it is 15 years old? I paid £149.00 in 2004
YNWaN
10-12-2019, 11:33
Are you sure it isn't just a question of reconnecting the ground wire from your turntable to the ground post on your phonostage?
tyke
10-12-2019, 11:45
Are you sure it isn't just a question of reconnecting the ground wire from your turntable to the ground post on your phonostage?

If only it were that simple!!
YNWaN
10-12-2019, 11:48
Alternatively, don't forget to try disconnecting said lead because, in some systems, that's the correct option.
Audio Al
10-12-2019, 12:44
Good question!! I paid £149.00 for the HiQ in 2004, so would imagine I would have to spend this amount today, pension permitting.
I would be reluctant to spend more than this, as I only listen to vinyl occasionally.

Right you ( In a John Cleese voice ) Get out now :door::lol::ner:
Ali Tait
10-12-2019, 14:34
Good question!! I paid £149.00 for the HiQ in 2004, so would imagine I would have to spend this amount today, pension permitting.
I would be reluctant to spend more than this, as I only listen to vinyl occasionally.

This is very good for the money-
https://www.longdogaudio.com/product/lda-ph1-moving-magnet-phono-stage/
Slawts
10-12-2019, 18:47
Or try one of the Rothwells.
jandl100
10-12-2019, 19:00
I could take a look at your current phono if you like?

Seems possible something has come loose inside, personally I'd take Alan up on his kind offer. :)
jandl100
10-12-2019, 19:04
When I was routing the second pair of speaker cables to the amp I accidentally pulled one of the inputs to the phono preamp. The preamp jumped off the rack, hit me on the bridge of the nose and landed, belly up, on the shag pile! I replaced it on the rack and only just managed to stop the blood dripping from the end of my nose onto the pale cream carpet....

Sorry to be long-winded but thought this might amuse some of you. Fortunately, I can laugh about it now.


I am embarassed to admit that your description of events did make me chuckle. :eyebrows:
Lawrence001
10-12-2019, 22:19
Could be the earth lead has come loose inside, worth having a look. Stick some internal photos up here if you like.
tyke
11-12-2019, 09:27
I could take a look at your current phono if you like?

I noticed when checking the connections yesterday that the hum is present whether the earth lead is connected to the phono preamp or not. So, I would like to take you up on your generous offer, if it still stands?
Firebottle
11-12-2019, 10:42
Sending a PM.
YNWaN
11-12-2019, 13:11
Oh, what I have come across before (and quite possible what Alan has suggested in his PM) is, when removing the RCA cable it’s easy to twist the plug and this can cause the socket to also twist. When this happens the positive and return wires can touch inside the unit where they are soldered to the RCA sockets. I’ve also seen something similar happen with the ground connection - all easy, quick and cheap fixes.
tyke
11-12-2019, 14:32
Oh, what I have come across before (and quite possible what Alan has suggested in his PM) is, when removing the RCA cable it’s easy to twist the plug and this can cause the socket to also twist. When this happens the positive and return wires can touch inside the unit where they are soldered to the RCA sockets. I’ve also seen something similar happen with the ground connection - all easy, quick and cheap fixes.

Thanks for that. The preamp is going to have a trip to Alan for him to inspect. Would be no good for me to look as I wouldn't know what to look for!