SOLD - JOHN H ATTENUATOR M

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Point 2 Point

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John H 50W M2 / 8 Ohm
Built by “Some Guy”
Excellent condition , just a few hours on it.
I just don’t use it.
Asking $318 shipped
Please PM with all questions.



This is basically the email manual:

Hi ,
OK, here’s the poop! Never, NEVER, NEVERtoggle the BYPASS switch unless the amp is off or in standby mode! Also do NOT use the BYPASS mode if using the 16 ohm output or if the load plugged out of the 8 ohm output is different than 8 ohms! Remembering that whatever impedance is plugged out of the 8 ohm output, is what the amp “sees”when in BYPASS mode (BYPASS switch in the up position), and that the 16 ohm output should only be used when the attenuator is active (BYPASS switch in the down position). The BYPASS switch use can get kinda complicated and often confusing (potentially causing amp damage, if used improperly), which is why I generally do not recommend them! This leaves the onus of understanding its proper usage on you, the user! In other words, if you blow up your amp, due to improper use, error and/or misunderstanding the particulars of the use of the BYPASS switch, that is all on you!Especially when including a BYPASS switch, this unit becomes a very high performance piece of HOT ROD gear and must be treated and used as such! Much like a race car, there are performance capabilities that can be dangerous when used improperly!

All switching on this attenuator unit utilizes the British/EU convention of down being “active/on”and up being “inactive/off.” The following is a list of the attenuation levels achieved through various switch combinations, when the attenuator is in “active/on” mode and not in BYPASS mode. This means the BYPASS switch is in and remains in the“down” attenuator active position:

1> All switches up = -7db attenuation. Remembering that this reactive/inductive stage is always on and active whenever the attenuator is on and active!
A> There IS a way to make this unit only achieve a -3.5db total attenuation, BUTthere are multiple details and impedance considerations surrounding it that we can discuss later, if and when you find it a necessary function!
2> Only -3.5db down = -10.5db total attenuation
3> Only -7db down = -14db total attenuation
4> Only -3.5db & -7db down = -17.5db total attenuation
5> Only -14db down = -21db total attenuation
6> Only -3.5db & -14db down = -24.5db total attenuation
7> Only -7db & -14db down = -28db total attenuation
8> All switches down = -31.5db total attenuation
Click to expand...
A> It should be noted that in this mode, the attenuator can be used as a stand alone load box, with no speaker attached, for multiple purposes! Line out or similar device out of 8 ohm output, etc, etc. Again, NEVER use the bypass when using this unit as a load box!
It should also be noted that you can use any impedance (4ohm, 8ohm or 16ohm) speaker out of the 8ohm output, but any impedance other than 8ohms may likely have a slightly different set of tonal characteristics. The 16ohm output has been specifically designed to compensate for this tonal difference, when using a 16ohm speaker load.

Fell free to email and/or call me with any questions. It is quite effective to verbally go over details in a phone call, as a lot of details and nuances can be lost, in the process of typing back and forth!

Enjoy,


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