Intercity AEF1plus [14/7 band Parametric Filterbank]

The Intercity AEF1+ is a high fidelity analog equalizer design that uses a parallel summing topology (14 bands and 4 filters) which avoids phase interactions. The dual/mono switch links L->R producing a 14-band parametric filterbank.

Historically most equalizer designs have relied on cascaded serial filters, while notable mastering EQs have favored parallel summation; Manley, ITI, GML, Sontec, Kush, Maag (*note the Maag Airband itself is serial). So, it's not surprising that this rare Japanese Hi-Fi EQ is "Parasum" topology.

Details:

• Each EQ band and filter features a discrete in/out switch
• True bypass provided via physical relays
• 18v rails provide extra headroom over your typical 500 series modules
• Each band can be positioned anywhere between 20Hz and 20Khz using a 3-way toggle switch reducing left-right mismatch common with other designs (e.g., GML)
• +/-15dB (cut/boost) per band
• Each band can be narrowly focused .3/Oct or spread beyond 1.2/Oct
• Left and Right channels offer a push-to-engage high-cut (48Khz--2Khz) and low-cut (400Hz--20Hz) filter

The manufacturers original specs are impressive:

- 0.008% T.H.D. at +4dBm (with all channels engaged)

- 120dB Dynamic Range (normal operating conditions, all filters in)

Much of the design utilizes discrete transistors over ICs (cost-no-object designs like this are completely thought out to the point of them being an art-form)

Build quality:

Solid chassis, quality pots, quality knobs, excellent-feeling to use. All switches feel robust. Layout is fast and friendly. Push-pots on the LPF/HPF filters are a nice touch. Everything lights up and works as expected. The PSU and caps are in good shape as demonstrated by metering, showing 17.99v at the test point.

Impression:

I use this EQ in a mastering chain to feed the usual suspects and it performs well. Time and again the Intercity has shown itself superior to plugins (Kirchoff, Fabfilter, Equilibrium, Sonnox). It's open to 40Khz giving Hi-Fi performance with a digital-like noise-floor. Although originally designed for Hi-Fi, the AEF1 excels in mixing, stem animation, room tuning, and mastering.

History:

Something of an undiscovered gem in the equalizer tree.

Item condition:

Not only is this EQ rare but they are hard to find in excellent condition. Based on the pots and pushbuttons, It appears to have seen minimal use although the previous owner somehow bent the case where the XLR cable plugs in. You can see this on the back panel near the XLR jack. I've used it for years in mastering context with no impact on the sound or mechanical functionality.

Terms:

Item will be insured for the full amount. Signature required on delivery. Item is clearly described and functions correctly, no returns. *I am reasonable and will work with you if something comes up.*

Included with the sale:

• Install shield that keeps curious hands off the EQ when you're using it for room correction (venue, studio or living room).

Not Included with the sale:

• 120v to 100v Step-down transformer (US->Japan. @amazon ~$50)
• The 2U rack is not included. If you'd like the rack make me an offer.