This is a new power amplifier from AUDIOPAX. After the huge success of the model eighty eight we have been working on a more conventional looking unit that could deliver the same kind of performance. Ok! You do not get the looks of the 88s, but who said that you need it? Or that you even wanted it? We have here a dual mono, 30 Watts per channel Class A Single Ended tube amplifier in an amazingly convenient and elegant package. Since it shares with the model 88 most of the components and it has benefited from a few new developments, it is, in itself, probably the most revealing, transparent and musically engaging amplifier you may have ever heard.

The most relevant technical features

The model 98 shares the same basic circuit with the model 88 our flagship model. The differences are the single chassis, the dual mono construction and the power supply that was changed to better adapt to dynamic direct radiator speakers. We kept all the unique features of the model 88 like:

• ASTAT - Asymmetrical Series-Twin Amplifier Topology
• PTS - Perfect Triode Simulator output stage circuit
• MPS - Matched Power Supply combines high speed and definition with exceptionally low noise
• Timbre LockTM - The world’s first system optimizer
• Unusually extended frequency response
• No global feedback used to achieve these outstanding specifications
  

Timbre Lock - the world’s first optimally adjustable amplifier/speaker interface

The interaction between amplifiers and loudspeakers has long been recognized as being of paramount impor-tance. Very little has been actually done to study it. Almost no one has tried to actually do something about it. After years of designing custom music systems that included the design of mostly single-ended amplifiers and carefully matched speakers, AUDIOPAX has developed a deep understanding of this subject. More importantly, we also introduced and implemented several practical ideas. Timbre Lock will give you the means to adjust your sound to achieve a level of refinement that is the essence of very well matched systems.

Timbre Lock gives you the power of “dialing in” the amplifier behavior that will be best for the system, not just for the amplifier.

Essentially, you can adjust your system to deliver your preference. You can bring vocalists into the room in a more intimate and vividly compelling manner, all at your command. Choose your level of musical articulation, combined with your specific requirements in terms of high frequency smoothness and extension, and how “relaxed” you’d like your music.

The output transformers

They are the “heart” of any tube amplifier. As much as people try to say that it would be better to avoid them entirely, we definitely do not agree. Everything is in the specific details and with output transformers, it’s about design and implementation. As our white papers explain, output transformers play a crucial role in creating the amplifier behavior that will result in better overall system performance.

AUDIOPAX output transformers for the model 98 are designed in house and are produced under our direct supervision. Like the transformers in the model 88 they truly represent a new kind of output device. They are much smaller than usual for the same output power. This is done because this is how we achieve our standard-setting performance; not because we want to save costs. Actually, in these transformers the materials cost is almost irrelevant when compared to the labor involved. We wind very precisely almost thirty different coils on the specially treated oriented grain iron core. More than that, as used in our ASTAT pairs, they have very slight asymmetries that help the pair achieve the intended result.

These exclusive AUDIOPAX single-ended transformers deliver a frequency response that’s amazing and totally unusual. If we consider just the output stage (rather than the entire amp), using the KT88 tube, they will deliver a high frequency –3dB point at over 100 kHz! At the lower end, we can expect something like –3dB at 18 Hz. These are measurements at 1 WRMS / 8 ohms. The power bandwidth and the transformer behavior under power are designed to conform to what our research has proven to be best for interfacing with average medium-to-high efficiency loudspeakers.