Nagra Pyramid Power Amps
I've known the name Nagra for decades, but only in the realm of professional audio, especially field recorders. Recently, I learned that the Swiss stalwart also offers a line of high-end consumer electronics, such as the Pyramid Monoblock Amplifier (PMA) and Pyramid Stereo Amplifier (PSA).
Where the names come from is obvious, but it's what's under the pyramid that counts. Both models offer solid-state class-AB operationthe PMA provides 200 watts RMS into 8Ω with a frequency response from 10Hz to 70kHz (+0/-3dB), THD under 0.09% at full power, and SNR typically 104dB, while the PSA divides the power between two channels (100Wpc) with otherwise identical specs. In addition, both feature Nagra's Power Factor Corrector (PFC) power supply, which "follows" the current coming from the input transformer and cleans it up before sending it to the amplification circuitry.
You can configure the PMA to accept balanced or unbalanced inputs, while the PSA is limited to balanced inputs. A switch on both enables or disables the auto-on function, which turns the amp on when it receives a signal and shuts it down after 15 minutes of silence. This is especially helpful when the amps are inaccessablethough they are attractive enough to want them visible.
Nagra gear is anything but cheapthe PMA goes for $12,300/pair, while the PSA costs somewhat less per channel at $7300. I'd love to hear five PMAs in a surround system, which would carry a price tag of $30,750. And as Nagra's US service manager told me, having all those pyramids around might generate some new-age spiritual energy in addition to outstanding music.