Problems with transformer hum. Advice wanted

[acompto]

Hi, all

I recently bought a new hifi setup, Arcam A19 amp, Kef R100 speakers, Rega RP3 turntable, Pioneer N50 streamer, Pioneer PD30 cd player.

Everything works well, I am very happy with the sound. However both the A19 and the N50 have a noticeable hum. Does anyone know if this is normal? I find it a bit annoying, but maybe I am too sensitive? I am thinking of getting an enclosed cabinet, which I guess would solve the problem, although this could be annoying for accessing the back on the components, especially the N50. Also, are amps, streamers more likely to have transformer hum compared to cd players? The PD30 is perfect. Is there anything I can do to reduce the hum? Maybe something between the units and the mains?

Thanks for your thoughts. All products are under warranty so I could try and send for repair.

 

[gasolin]

http://www.thomann.de/gb/art_dti.htm

 

[acompto]

Thanks. The hum is coming from the units, so best to try the voltage stabilizer. I don't know much about this sort of thing, so forgive my stupid questions! Does the stabilizer plug into the power socket and the cable from the amp/streamer plug into the stabilizer?

Many thanks

 

[Vladimir]

I have this particular one - EnerGenie EG-AVR-1001 Automatic AC voltage regulator and stabilizer. http://energenie.com/item.aspx?id=6874 I bought mine from a PC shop, but you can order online, just make sure you buy a stabilizer that matches the voltage for UK (230V, 50Hz).

You plug the AVR in the mains and your units in the AVR. Its basically a transformer and voltage regulator tranzistor that will take the beating from the dirty power in the mains instead of your hi-fi gear.

They are cheap so no harm if it wont solve the problem. You can use it for your PC, its an excellent protection from power surges and brownouts.

 

[acompto]

Thanks for the information, very helpful. I just looked on Amazon and it looks like this would work in the UK.

http://www.amazon.co.uk/Aiptek-PowerWalker-AVR-1000-Automatic/dp/B004DT3MIG/ref=sr_1_fkmr0_2?s=computers&ie=UTF8&qid=1397830756&sr=1-2-fkmr0&keywords=voltage+stabilizer+va1000

Out of interest, do you know why some units are fine, for example the cd player, and others like the streamer hum? Is it a build issue?

 

[Vladimir]

If it's a humm coming from the units, not from the speakers, I'd suggest buying a decent UPS or a voltage stabilizer. The bigger the better since more headroom in VA benefits amplifiers.

How much are you willing to spend? I would try a cheap voltage stabilzier 1000VA for £20-30 first. If it solves your problem it is up to you if you want a better one as an upgrade.

If the humm comes through the speakers, then you have ground loop issue and that previously suggested ART DTI will solve that problem.

 

[Vladimir]

IME not a build issue as much as mains electricity getting worse and worse.

A lower power unti is less prone to humm because the transformers are not big enough, but the N50 has two medium sized transformers enought to make a decent amp out of them.

Older amps can begin to humm because the transformer screws are loose or need new coat of lacquer. But in your case both new, the amp and the streamer are humming, IMO i is clear you have mains voltage issue.

I'm not an electrician, I just have these same issues throughout the years with my gear. I hope the voltage stabilizer helps like it helped in my case and it wont be a waste of 35 quid.

Some people complain the voltage stabilizers, UPS, power filters, regenerators etc. reduce amplifier dynamic punch and bass extention. It depends on the amp design and the owners listening habits and preferences.

 

[andyjm]

It's not the voltage, but DC offset on the mains that causes transformers to saturate and buzz.

All transformers hum to a certain degree, so take the offending device to a mates house and listen to the hum there. If the hum is about the same, then it's probably just a noisy transformer. If it is quieter, you may benefit from a DC blocker on the mains feed at home. A number of devices will block DC, an isolating transformer, purpose made DC blocker, UPS, regenerator. A surge protector however will not.

 

[Vladimir]

Yup. A surge protector is basically a fuse, not much to it.