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Thunderfunk Bass Amp Owner’s Manual
April 2007 - revision 8
Thunderfunk Bass Amp Owner’s Manual
Thermal Issues
– The Thunderfunk bass Amp was originally designed without a fan. This allows
super-quiet operation for studio and TV work. However, the amps do now have fans with an on/off switch.
If the amp is being used where the noise of the fan isn’t a problem, turn it on. If you’re in the studio, leave
it off. It’s up to you. With or without the fan, the bottom of the amp gets hotter than the top, so you should
avoid putting other equipment underneath it if installed in a rack mount. The amp itself is designed to
handle as much heat as it can generate AS LONG AS THE LOAD IS KEPT TO A 4 OHM MINIMUM.
Thermal Tip:
Power Transistors fail not so much from overheating, as from thermal cycling. It’s from the
growing and shrinking of the transistors due to a rapid change in temperature. For this reason it is advised
that if the amp comes in from cold storage, for example from the trunk of your car in winter, you should
allow time for the amplifier to warm to room temperature before turning it on. This should only take 30
minutes, as aluminum is an excellent thermal conductor, with a low thermal mass. To warm the amp up
faster, turn the amp ON after a few minutes, but don’t play through it. Make sure the fan is ON to circulate
room temperature air through it for another 10 minutes. This will allow it to warm itself thoroughly at a low-
heat level before you play through it. It’s the idea of letting it warm slowly, to prevent thermal stress cracks
in the transistors. It doesn’t hurt the amp to turn it on when it’s cold, as long as you’re not playing through
it. It also doesn’t hurt to operate the amp without a speaker attached. For the same reason, it’s not
necessary to turn the amplifier off between sets. It generates heat in direct relation to how much power it’s
putting out. When you’re not playing through it, it’s not getting hot, and the fan is actually cooling it off.
MECHANICAL AND ELECTRICAL ISSUES
Electricity and Water DO NOT Mix. Operating the amp near water can put your life at risk. Your amplifier
should therefore always be stored and operated away from moisture or water.
Your amplifier is sturdy, but it is also a delicate instrument. While Thunderfunks are made for the road,
care should be taken not to drop, throw, drive over, or otherwise suffer unusual abuse.
CONNECTIONS
The most quiet, dynamic and musical results are achieved when all instrument, effects, line-level, and
other source connections are made with high-quality shielded cables. There is much fuss these days
about recent improvements in these connections. Use your own judgment. The use of speaker cables for
line connections will result in excess noise, and is not recommended.
Speakers should be connected with high quality speaker cables. The lower the gauge number, the thicker
the wire, and the more power will be delivered to your speaker system. Speaker cable lengths should be
kept as short as possible for the same reason. The use of instrument cables for speaker connections can
cause damage and malfunction.
RECOMMENDED SPEAKER-WIRE GAUGE GUIDE
Maximum recommended wire length at 4 ohms. Running at 8 ohms reduces the power to 300 watts, and
you can easily double the recommended wire length for a particular gauge.
18 gauge = 10 feet or less
16 gauge = 15 feet
14 gauge = 20 feet
12 gauge = 30 feet
10 gauge = 50 feet
This is for a 5 amp rating, although the amp can put out over 10 amps, in practice, this is not on a
continuous basis. This chart is for a rated 50% duty cycle, which is still above average usage, which I
estimate is actually at 20%.
