News

Gryphon Unveils the Diablo 333 at Two Dealer Events

Stereophile Staff | Nov 10, 2023

Gryphon’s highly anticipated Diablo 333 Integrated Amplifier will make its North American dealer debut on Thursday 16 November, 11am–6pm, at The Sound Environment in Omaha, Nebraska. Anthony Chiarella, Gryphon's North American director of sales and marketing, will present the amplifier and be available to answer questions and discuss the Gryphon brand. Appointments are recommended. After 6pm, The Sound Environment will host an official presentation, with all invited. For more information or to book an appointment, please contact Charlie Santmire by email at info@soundenvironment.com or by phone: (402) 391-3842.

The following day, Friday 17 November, Anthony will present the 333 at Gryphon’s Chicago-area Dealer, Kyomi Audio, in Addison, Illinois. Kyomi's owner, George Vatchnadze, is a world-renowned concert pianist and professor whose knowledge of music and reproduced sound is unsurpassed. Anthony will present during showroom hours, and George will host a special event after 7pm. For more information, please contact George Vatchnadze by email at info@kyomiaudio.com or by phone: (312) 513-2759.

COMMENTS

Real high bias BJT amps, for real evil loads.

Submitted by georgehifi on November 10, 2023 - 3:31pm

Yes these high bias BJT amps are bad for the environment, but they sound the best to audiophiles.

We are a bit like "environmentalist surfers" who ride surfboards that last a season or two and end up in landfill, and are the worst pollution product ever to manufacture and dispose of.

But these BJT amps drive real difficult loads, not just a 20 "peak amps" like Class-D mosfets, but can do more than twice as many "continuous amps" into hard loads, and sound better into them because of it.

Can't wait for JA to bench test this one, (and not have to use the AP AUX-0025 filter) so we see what really coming out of it's rear end.

Cheers George

measurement filters for switching amplifiers

Submitted by JRT on November 11, 2023 - 6:30pm

George,

You seem to often insinuate that there is some sort of problem with filtering out inaudible ultrasonic content when measuring class D switching amplifiers.

"The switching process adds fast rising edges at the switching frequency to the audio output signal. These fast edges are of no consequence to the typical load (a loudspeaker), but present a difficult signal for measurement instruments. The fast switching edges present high energy content and will introduce slew rate limiting when presented to the input stage of most measurement instruments. When stressed by these fast edges, the analyzer input amplifier will usually slew rate limit and will not be able to function effectively in its normal mode. Auto ranging will be affected and the signal under test will be misrepresented to the following measurement circuits. The result is that noise and distortion measurements of switching amplifiers with almost any analyzer without preconditioning will yield inaccurate and unpredictable results." - excerpted from AP's website from a webpage available at the following link

https://www.ap.com/analyzers-accessories/accessories/aux-family-switching-amplifier-measurement-filters/

Below is the amplitude response of the AP AUX-0025. Note that this is near flat well beyond 20_kHz, and is only down -6_dB at 100_kHz. That is more than adequate to discern clipping level at 11.025_ kHz (44.1/4) where signal can reach maximum +3_dB above 0_dBFS on intersample overs in upsampled/oversampled Redbook CD audio (well explained at Benchmark's website).