Toad_of_Toad_Hall
100+ Head-Fier
- Joined
- May 25, 2017
- Posts
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I've just placed an order for a pair of HE560s with Jan for $495.00 USD (part of his November sale). I don't think that price can be beaten anywhere. Jan has also given me his permission to post his email response to my issue here on HeadFi:
____________________________________________
Dear Nathan,
> On the high gain setting there is audible transformer hum between 2
> o'clock and 6 o'clock on the knob.
Any amplifier will produce background noises and transformer humm. It
simply can't be prevented.
However, what's important is the Signal to Noise Ratio. Do you hear the
background noises at normal listening levels or not.
Most probably you did your test with a rather sensitive (low impedance)
headphone. At 2 o'clock while listening to music you would blow your ears.
The HE-560 is less sensitive than most other headphones. As a result you
will not hear humm at 2 o`clock. The signal simply isn't large enough to
become audible with an insensitive headphone.
As said, at normal listening levels with any headphone the background
noises of the JAZZ are not a problem.
> 1. Do you envisage that I will need to turn up the knob to or beyond 3
> o'clock with the HE560s?
Strongly depends on the output level of your source.
But at 3 o'clock you won't hear hum with the HE-560 because the
headphone is not very sensitive.
> 2. Is it normal for the Jazz to have the hum I described?
Yes, due to the small enclosure the internal transformer is placed
rather close to the amplification circuitry. It's a simply matter of size.
Question: Was the input of the amp opened or short-circuited when you
did testing?
Cheers
____________________________________________
Dear Nathan,
> On the high gain setting there is audible transformer hum between 2
> o'clock and 6 o'clock on the knob.
Any amplifier will produce background noises and transformer humm. It
simply can't be prevented.
However, what's important is the Signal to Noise Ratio. Do you hear the
background noises at normal listening levels or not.
Most probably you did your test with a rather sensitive (low impedance)
headphone. At 2 o'clock while listening to music you would blow your ears.
The HE-560 is less sensitive than most other headphones. As a result you
will not hear humm at 2 o`clock. The signal simply isn't large enough to
become audible with an insensitive headphone.
As said, at normal listening levels with any headphone the background
noises of the JAZZ are not a problem.
> 1. Do you envisage that I will need to turn up the knob to or beyond 3
> o'clock with the HE560s?
Strongly depends on the output level of your source.
But at 3 o'clock you won't hear hum with the HE-560 because the
headphone is not very sensitive.
> 2. Is it normal for the Jazz to have the hum I described?
Yes, due to the small enclosure the internal transformer is placed
rather close to the amplification circuitry. It's a simply matter of size.
Question: Was the input of the amp opened or short-circuited when you
did testing?
Cheers