Laney IRT30-112 - Manual (Page 12)

12
TUBE AMP TIPS
Tube amplifiers generally sound much warmer/sweeter than solid state transistor amplifiers but they also need a little more
respect due to the fragile glass tubes. Use the following steps as a guide for how to take care of your amplifier: Take care when
moving the amplifier. Tubes are fragile glass components, they can easily be damaged if thrown in and out of vans.
Make sure the impedance of your cabinets matches the setting on your amplifier. Improper impedance matching will result in
reduced output power and compromised sound at best, and amplifier failure/shortened tube life at worst. Allow the amplifier to
warm up to room temperature before switching it on: the sudden thermal shock can crack a cold glass tube enclosure, plus any
moisture is bad news around high voltage electronics. After playing, allow the amplifier to cool down before moving. Hot tubes are
more fragile than cool ones. Always use good quality loudspeaker cables: instrument cables are not capable of handling the load
requirements of the loudspeaker and can short out.
A tubes life expectancy is based upon a number of factors which include operating temperature, how hard and how often it is
played, vibration due to travel, etc. Tubes should be changed in your amplifier if you notice any deterioration in your amplifiers
sound or performance. Otherwise, they need not be changed at any regular interval.
Typical problems with preamp tubes can be crackly noise, hiss, hum, and microphony. If they fail or exhibit reduced performance,
preamp tubes can simply be swapped out with no
further action required.
Typical output tube problems can include a blown
HT fuse, sound lacking in punch, sound lacking
extreme highs or lows, and low level hum. The
output tubes can be replaced singly if you replace
them with the exact same type AND grade as
factory fitted, otherwise they should be replaced
as a matched pair.
V1 - ECC83 HiGrade 005571
V2,3 - ECC83 Selected 005550
V4,5 - 6L6GC-STR (Matched Pair) 007853
V1 V2 V3
V4 V5