reflux075 Posted November 10, 2018 Share Posted November 10, 2018 Hi peeps, having a bit of an issue I cannot really work out. I have a primaluna prologue premium preamp that I was using with a classe fifteen power amp. No buzz/hum with this combo. The classe was a stop gap while my monarchy audio se-100 mk2 amps were getting repaired. Got the monarchy back this week and when I plugged them in there was quite a bit of buzz/hum with the volume at zero, it does not get any louder when I turn the music up but it is still there behind the music. I tried using an old ss pre with the monarchy and the buzz/hum goes away. Is it my primaluna that is the issue? or is it the monarchy? or is it something else? All the same cables were used in all the different combinations. Any ideas as to what is causing this buzz/hum, is it safe to use the combos that cause it, and is there anything I can try to reduce or eliminate it? Thanks Link to comment Share on other sites More sharing options...
Guest Muon N' Posted November 10, 2018 Share Posted November 10, 2018 (edited) Do you have power sources (cables & power transformers) well away from signal leads and the pre amp itself? I can't see anything in the spec's of the primaluna and se-100 mk2 amps that would suggest a matching issue. Edit: if you can't find any set up issues I wouldn't rule out the amps still having an issue after repair, but need to eliminate other possibilities first. Could be a valve playing up in the pre, coincidences like this do happen, and cause much frustration when it coincides with another event. But then the buzz/hum is from both channels? if so, it would be unusual as there are no tubes shared between channels with the pre so it would have to be two tubes playing up, hmm... Eh, someone else will help with other ideas. Edited November 10, 2018 by Muon N' Link to comment Share on other sites More sharing options...
georgehifi Posted November 10, 2018 Share Posted November 10, 2018 4 hours ago, reflux075 said: I have a primaluna prologue premium preamp that I was using with a classe fifteen power amp. No buzz/hum with this combo. The classe was a stop gap while my monarchy audio se-100 mk2 amps were getting repaired. Got the monarchy back this week and when I plugged them in there was quite a bit of buzz/hum with the volume at zero, it does not get any louder when I turn the music up but it is still there behind the music. You've gone from a stereo Classe DR15 with one earth point, to two mono blocks with power cords that both have earth pins. You now have an earth loop through the house wiring with these two earth points. Do some reading on monoblocks and ground (earth) lifts. Cheers George 1 Link to comment Share on other sites More sharing options...
Zaphod Beeblebrox Posted November 10, 2018 Share Posted November 10, 2018 You must specify if the noise is a 'buzz' or a 'hum'. The two are very different, with different causes. Link to comment Share on other sites More sharing options...
Ittaku Posted November 10, 2018 Share Posted November 10, 2018 Buzz and hum are both harmless but very annoying. You need to differentiate if the buzz is new and coincidence or an interaction between the pre and power amp. Try the primaluna preamp into another power amp to differentiate. I had a problem with both in my own system when I mated a very high gain preamp with a high gain power amp. Using shielded power cables to the preamp helped, as did moving the preamp as far away as possible from other components. However, in the end nothing could make it go away entirely short of a different preamp. In the end the designer of the preamp addressed it through a redesign and complete rebuild. Buzz be gone now. 1 Link to comment Share on other sites More sharing options...
andyr Posted November 10, 2018 Share Posted November 10, 2018 6 hours ago, reflux075 said: I tried using an old ss pre with the monarchy and the buzz/hum goes away. Which would suggest the problem is with the primaluna prologue premium preamp - as your Monarchy monoblocs are fine with the "old ss preamp". 6 hours ago, reflux075 said: Any ideas as to what is causing this buzz/hum, is it safe to use the combos that cause it, and is there anything I can try to reduce or eliminate it? Thanks Alternatively ... I had a problem like yours (with buzz through the speakers) many years ago when Trevor Lees lent me a tube amp to try out in my system. It turned out that the tube amp did not isolate its RCA input sockets from its chassis - and this produced a ground loop in my system. Is it possible your Monarchy amps don't isolate the input RCAs from the chassis (whereas the Classe did)? Andy Link to comment Share on other sites More sharing options...
Zaphod Beeblebrox Posted November 10, 2018 Share Posted November 10, 2018 Just to clarify, because it appears that some are mis-informed: A 'hum' is what happens with an Earth loop. A buzz can have many causes, including (but not limited to): * Poor Earthing somewhere. * Power supply problems. * Lots of other things. A 'hum' is a 50Hz signal. IOW; It is low frequency and no sound can be heard from mid and HF drivers. A 'buzz' has a range of components impressed upon a basic 50Hz or 100Hz fundamental, such that noise will emanate from all drivers in a speaker system. So, the question remains: Hum or buzz? It is a very important question. 2 Link to comment Share on other sites More sharing options...
reflux075 Posted November 10, 2018 Author Share Posted November 10, 2018 (edited) If I had to pick one, I think it is more of a buzz. The sound is coming from all the drivers. Edited November 10, 2018 by reflux075 checked drivers Link to comment Share on other sites More sharing options...
Zaphod Beeblebrox Posted November 11, 2018 Share Posted November 11, 2018 18 minutes ago, reflux075 said: If I had to pick one, I think it is more of a buzz. The sound is coming from all the drivers. Good. Buzz, it is. It is unlikely to be an Earth loop (though not impossible). Possibly a shielding problem, somewhere. Link to comment Share on other sites More sharing options...
eltech Posted November 11, 2018 Share Posted November 11, 2018 Does the valve preamp cause buzz when connected to any other power amp? Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 1 hour ago, eltech said: Does the valve preamp cause buzz when connected to any other power amp? Nope, no buzz when valve pre connected to classe amp. Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 1 hour ago, Zaphod Beeblebrox said: Good. Buzz, it is. It is unlikely to be an Earth loop (though not impossible). Possibly a shielding problem, somewhere. I will try and rearrange all the cables. Link to comment Share on other sites More sharing options...
Zaphod Beeblebrox Posted November 11, 2018 Share Posted November 11, 2018 4 minutes ago, reflux075 said: I will try and rearrange all the cables. Check the shielding. Link to comment Share on other sites More sharing options...
Grumpy Posted November 11, 2018 Share Posted November 11, 2018 I recently posted about my systems buzz problem and finding it was the rca between the pre and power amp. Can you touch and move your interconnect cables a little while the system is on but not playing ? I found my faulty rca this way when the buzz got louder while touching it Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 15 minutes ago, Zaphod Beeblebrox said: Check the shielding. Will do that. 3 minutes ago, Grumpy said: I recently posted about my systems buzz problem and finding it was the rca between the pre and power amp. Can you touch and move your interconnect cables a little while the system is on but not playing ? I found my faulty rca this way when the buzz got louder while touching it And that as well. 1 Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 6 hours ago, andyr said: Is it possible your Monarchy amps don't isolate the input RCAs from the chassis (whereas the Classe did)? Andy No idea about this? Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 11 hours ago, Muon N' said: But then the buzz/hum is from both channels? if so, it would be unusual as there are no tubes shared between channels with the pre so it would have to be two tubes playing up, hmm... Eh, someone else will help with other ideas. Buzz is from all drivers on both speakers. Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 I swapped speakers and the buzz has gone ALOT softer, it's at a level that I can live with. Sometimes this hifi business is like some sort of black art Will probably stay with this combination, thanks everyone for your help! Link to comment Share on other sites More sharing options...
Grumpy Posted November 11, 2018 Share Posted November 11, 2018 No no no , you must find the cause if it is still there even though it is less noticable - it would drive me crazy Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 2 minutes ago, Grumpy said: No no no , you must find the cause if it is still there even though it is less noticable - it would drive me crazy I will pull the hifi rack out next weekend and sort out the rats nest of wires. I think @Zaphod Beeblebrox is right about shielding, my speaker cables are lenehan rtek which I believe do not have much shielding, though my power cables are mostly quite well shielded. Will get to the bottom of it and report back 1 Link to comment Share on other sites More sharing options...
Grumpy Posted November 11, 2018 Share Posted November 11, 2018 You changed to a different set of speakers and the buzz is less noticeble, is that correct ? If so the old speakers might be more sensetive perhaps ? Link to comment Share on other sites More sharing options...
georgehifi Posted November 11, 2018 Share Posted November 11, 2018 (edited) 48 minutes ago, reflux075 said: though my power cables are mostly quite well shielded. Shieled power cables? that "just maybe" illegal in Australia. Cheers George Edited November 11, 2018 by georgehifi Link to comment Share on other sites More sharing options...
Ittaku Posted November 11, 2018 Share Posted November 11, 2018 2 hours ago, reflux075 said: I will pull the hifi rack out next weekend and sort out the rats nest of wires. I think @Zaphod Beeblebrox is right about shielding, my speaker cables are lenehan rtek which I believe do not have much shielding, though my power cables are mostly quite well shielded. Will get to the bottom of it and report back Usually only small signal cables are affected by lack of shielding, meaning interconnects. Power cables without shielding can also emanate noise. Relatively high current/high voltage cables, such as speaker cables are usually unaffected by lack of shielding, though they can give off significant magnetic fields. Buzz is usually not in the speaker cables. Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 2 hours ago, georgehifi said: Shieled power cables? that "just maybe" illegal in Australia. Cheers George Haha, yes, I believe the Audio Principe power cables are not certified, but they sound so good. Link to comment Share on other sites More sharing options...
reflux075 Posted November 11, 2018 Author Share Posted November 11, 2018 58 minutes ago, Ittaku said: Usually only small signal cables are affected by lack of shielding, meaning interconnects. Power cables without shielding can also emanate noise. Relatively high current/high voltage cables, such as speaker cables are usually unaffected by lack of shielding, though they can give off significant magnetic fields. Buzz is usually not in the speaker cables. I believe the Aurealis R1 interconnect cables I have have no shielding. Link to comment Share on other sites More sharing options...
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