Ion Nexus

Ion Nexus range

Ion Nexus SP1 preamp and X-PAK 2 Power Supply
Ion Nexus SP1 Preamp and X-PAK 2 Power Supply

The “Nexus” range of equipment was Ion Systems’ premium range of equipment and consisted of a single preamp, the SP1 and a number of different power amplifier systems with a somewhat confusing numbering system.

All Nexus components can still be serviced and repaired.
Contact us for latest details and prices.

SP1 Preamp

Nexus SP1 preamp
Nexus SP1 preamp
SP1 and X-PAK 2 rear panels
SP1 and X-PAK 2 rear panels

The SP1 was the only preamplifier in the Nexus range. The SP1 had four inputs (Disc, Tuner, CD/Aux1, and Aux2). The SP1 also had two “tape monitor” i/o connectors with the ability to dub between tape 1 and tape 2.

Like the Obelisk 3 the SP1 had a choice of MM or MC phono input boards.
The SP1 however had an extra “line level” plug in board on Aux 2 which was compatible with the phono input boards so the SP1 could have two phono inputs, two line level inputs or a mixture of both depending on which boards were fitted.

The SP1 requires a 33v AC power supply which was normally provided by the X-Pak 2 power supply or directly from the “System” power amplifiers.

XPak 2 Power supply

X-PAK 2 Power supply
X-PAK 2 Power supply

The Xpak 2 power supply was a stand alone power supply for the SP1 preamp and the SP40 power amp.
Essentially a large 500vA torroidal transformer in the same size matching case as the SP1 / SAM40 with two 2x33V AC outputs for the SP1 and SAM40.

SAM40 Power amplifier

Nexus system SP1/SAM40/X-PAK 2
“Entry level” Nexus system SP1/SAM40/X-PAK 2

The SAM40 was the “entry level” power amplifier in the Nexus range.
It was actually the power amplifier board from the Obelisk 3X with an additional board for the Ion nexus active crossover board.

The SAM40 required the Xpak2 power supply to work so the basic Nexus system was SP1 / SAM40 / XPak 2.

System 240 and 140 Power amplifiers

Ion System 240 Stereo power amplifier
Ion System 240 Stereo power amplifier
Rear view of a System 140 monoblock
Rear view of a System 140 monoblock
System 140 showing MA40 (right) and TX750 (left)
System 140 showing MA40 (R) and TX750 (L)

This is where things get a little confusing with the bigger Ion power amplifiers.

The System 240 poweramp was a stereo amplifier and the System 140 was a monoblock

The “System” power amplifiers were modular and consisted of a TX750 power supply and two (System 240) or one (System 140) MA40 power amplifier modules all mounted in one very big box (double height and width compared to the SP1).

The TX750 transformer was huge (750VA) considering the MA40s were rated at only 40W RMS, but the MA40s had a massively uprated output stage (8 output transistors instead of two) as the System 240 stereo amplifier could be “bridged” to produce an 80W power amplifier with a very high current output capability and was capable of over 160W into a low impedance speaker.

MA400 Monoblock power amplifier

Rear view of a pair of MA400 monoblocks
A rear view of a pair of MA400 Monoblocks

The MA400 replaced the System 140 monoblock, retaining the same MA40 poweramp module but with a smaller transformer. This enabled Ion to reduce the height of the MA400 to be the same as the SP1. This made a smaller overall system as two MA400s were the same size as a System 240 but with separate power supply transformers and improved stereo focus.

FMT1 Tuner

FMT1 Tuner
FMT1 Tuner

The FMT1 was the Nexus FM tuner.

Based on the Nytech CT206 but with a digital frequency display and LED bar graph tuning/signal strength meters.

The FMT1 was self powered so could be used with any equipment, not just with the Nexus amps.