Noisy Transformer

I've tried two new INT-25 integrated amps, which both have annoying buzzing sounds from the toroidal transformers. I've never had an issue with Leema amps, Musical Fidelity amps, Denon amps or a Naim Nait 5i. I love the sound of the Pass, but I can't stand hearing the transformer between every track. Also, using the room for anything other than music is impossible as the buzzing makes reading impossible to concentrate on.
 
Official Court Jester
Joined 2003
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If you tried them, that means you got them from some Dealer

Take that issue back to Dealer, that's only logical

What's the purpose asking here?

I mean, if you're simply curious to know a reason, not getting adequate answer from Dealer, write to PL directly

and yes, buzzing xformer is not acceptable, from any Factory
 
If you tried them, that means you got them from some Dealer

Take that issue back to Dealer, that's only logical

What's the purpose asking here?

I mean, if you're simply curious to know a reason, not getting adequate answer from Dealer, write to PL directly

and yes, buzzing xformer is not acceptable, from any Factory
The Official UK Supplier, Select Audio, is ignoring my emails. :(
 
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Joined 2014
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Can you describe the buzzing transformer in more detail? Like how far away you have to be to hear it, is it coming through the speakers etc. Does it do it with sources, speakers etc disconnected?

You can post some pics here of your setup if you like. That could give us more insight.
 
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Hi Guys, I've followed all the advice you gave me. I first tried an iFi DC Blocker: no difference. Then a Mains Conditioner: no difference. Today I turned off all other appliances: no difference.

I've emailed Pass Labs requesting they help me. I'll keep you updated on any help they offer me. I'm losing faith in Pass Labs gear, and I don't want that to happen. If I can get this horrid toroidal transformer to stop vibrating, I would happily buy more of the brand. This is a great chance for Pass Labs to demonstrate how they can help their UK Customer base when they have a problem with a brand new amp purchased from the official UK Supplier [Stephen at Select Audio], and it turns out not to be working as it should.
 
"Slightly bothersome was some mechanical hum from the INT-150's transformer, as well as some barely audible ground buzz coming through my speakers. I tried various power cords and different outlets in my room, but the INT-150 always wanted to make a little noise. This was barely audible at my listening seat between tracks, but I still would have rather not heard it at all". Stereophile Magazine article.
 
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Joined 2002
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Noise in an INT-25 isn’t something we hear about. Avel Lindberg makes that transformer and it is supposed to be their lowest noise design something we continually try to improve with our transformer partners. We are ready to help.
 
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Hi Wayne,

This is incredible for me to hear from you. I don't know any other company where the Designer would reach out to a customer. I bought into the brand because I watched many YouTube videos of you and Nelson. I liked that I never saw either of you use foul language. As a Christian, that impressed me. I really want to love your products - I already love the sound, build, and look of Pass Labs gear. I only have this one issue - the vibrating transformer that I can hear from my listening position of 6 feet away, and it can also be heard further than that. When first turned on, it is acceptably quiet, but as it warms up, it can be unbearable to read a book or do anything other than drown it out with music. But then I hear it in between the tracks. How shall I proceed?
 
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Dunk it in varnish when warm, preferably on load, that will act as a vibratory feed.
Let it drip off and settle, and air dry.

Insulating varnish intended for Class F or B motors is ideal, furniture varnish will also do.

Many threads here about it.
If the maker is not answering your e-mails, he knows what he sold you is not what he said it was.
You could take them to court, if you feel you have a case.
Or ask for a refund / replacement, if under warranty.

Oh, and toroids can be fussy about mounting, the center bolt and insulators are important. See if they are properly fitted.
 
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Official Court Jester
Joined 2003
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considering that game is in UK, ball should be completely in local dealer's yard

nothing with PL factory - they didn't sell amp to OP

now, information that their dealer in UK isn't exactly behaving properly, that's their business

we will help anything we can (advise) in case of dealer gone in the woods; again, dealer's responsibility to solve problematic product is out of any doubt
 
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Check the paperwork, are they still covered in warranty?

Do you have a consumer forum / court / representative body in your country?
It is a much faster and easier way of dispute resolution compared to the regular courts here.

If the sellers do not respond, you may have to do it through a legal process.
 
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The Transformer can be heard from more than 10 feet away. It seems to get louder as it warms up. The UK importer [Select Audio] liaised with my dealer Audio Emotion in Scotland and thought they were sending someone to check the Pass Amp in situ. I've yet to hear from Audio Emotion. I'll keep you updated—many thanks.