Laney IRT30-112 User 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