In This Section
Reflecting on Reflections - June 2014
Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback - September 2007
Quiet Thoughts on a Deafening Problem - May 2014
AES Journal Forum
Noise in Triodes with Particular Reference to Phono Preamplifiers
Several types of triodes tubes that are popular in audio preamplifiers were tested under typical operating conditions to determine the relationships between noise and operating conditions. In most cases the total noise in the audio band was dominated by the flicker effect. Most triodes exhibit an optimum anode current at which the equivalent input-noise voltage reaches a minimum, and this current value is relatively consistent between samples of the same type. In general, high-gm triode types are likely to exhibit superior noise figures compared to low-gm types for a given mean anode current. Reduced heater voltage tends to reduce equivalent input noise at small anode currents, but tends to increase it at higher anode currents. A general formula for estimating the equivalent input-noise voltage for any conventional small-signal audio triode, at rated heater voltage, is presented.
No AES members have commented on this report yet.
Subscribe to this discussion
Start a discussion!
If you are not yet an AES member and have something important to say about this report then we urge you to join the AES today and make your voice heard. You can join online today by clicking here.