Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: pbman1953 on March 29, 2022, 01:52:21 pm

Title: Tube amp and line regulation
Post by: pbman1953 on March 29, 2022, 01:52:21 pm
I know some guitar players that like and use the Brown Box attenuator. But do any tube amp bass player use line regulators?


Is that something that should be considered?




Title: Re: Tube amp and line regulation
Post by: tubeswell on March 29, 2022, 04:08:51 pm
line regulators?


Do you mean voltage regulators?


(And if so, where do you mean to use this? Schematic Please)
Title: Re: Tube amp and line regulation
Post by: pbman1953 on March 29, 2022, 04:10:15 pm
no, more of a wall unit for stable power
Title: Re: Tube amp and line regulation
Post by: SILVERGUN on March 29, 2022, 05:48:29 pm
Skip to about 9:40 to hear how Angus uses one:
Title: Re: Tube amp and line regulation
Post by: HotBluePlates on March 29, 2022, 08:27:10 pm
... a wall unit for stable power

Like everything else, the good ones are fabulously expensive.

You might be able to get by with a Kikusui that costs only $2500-3000, but the ones highlighted by AC/DC and Bonamassa are more like $5-7000.


Meanwhile, folks will praise their Furman line voltage "regulators."  These things are basically a transformer with multiple discrete taps, about 5v apart.  A sensing circuit detects the voltage being sent to the outlets and switches to a different ta if that voltage is too high/low.

That means voltage is allowed to rise/fall within a ~5v window, unchecked.  Only when it goes beyond that does the unit switch to a different tap.  In a worst-case, this means a 1v variation of wall voltage from 1/2v below a switching-point to 1/2v over will result in a -4.5v change in the outlet voltage.

See the saw-tooth shape of the "Regulation Range" on Page 2 of Furman's data sheet (http://resources.nortekcontrol.com/products/P-1800-AR/pdf_P-1800-AR_datasheet.pdf).  At a price of $1500, buyers don't like it when you point out it can be worse than "no regulation at all" under the wrong circumstances.