Intercity AEF1plus Parametric Stereo Equalizer

The Intercity AEF1 plus is one of the pinnacles of analog equalizer design, in league with cost-no-object designs from Avalon, Neve, Sontec, ITI, GML, etc. Not only are Intercity’s rare, but they are hard to find in excellent condition. This particular Intercity was pulled from a performing arts theater in Japan. It appears to have seen minimal amounts of use as it was dialed to the room response and probably left alone for more than 15 years.

We made a video (linked below) that demonstrates the working condition of this unit. The camera microphone only gives a glimpse into the sound quality of this device:

https://www.youtube.com/watch?v=WX1bjE5BLw0

This is the 3rd and last generation of the Intercity AEF1 design and thus has the most circuit refinement.

The topology is a minimum phase design. It has an industry unmatched block count of 7 fully parametric bands (not sliders, but full bandwidth+freq+gain controls). It can also cascade the left and right channels to do 14 Bands of fully parametric EQ.

- Each EQ Band features a bypass function, and relays are used to avoid unnecessary artifacts when the circuits are not in (a mastering consideration).

- Unlike most high-end EQs, each Intercity Band can be positioned anywhere between 20Hz and 20Khz using a 3-way toggle switch (providing good dial range for precision tuning).

- +/-15dB (cut or boost) per Band

- Each Band can be sharply focused to a single note or more widely spread beyond an octave.

- Each Channel (left/right) features a push-button engaged high-cut (2Khz~48Khz) and low-cut (20Hz~400Hz)

The manufacturers original specs are superlative. Being Japanese, I believe they actually measured as such when leaving their shop: - 0.008% T.H.D. at +4dBm (with all channels engaged)
- 120dB Dynamic Range (normal operating conditions, all filters in)
- I haven’t fully confirmed the circuit but it appears all ICs run at +/-18v (providing more headroom and excellent noise specs) - 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)
One of my Intercity was professionally bench tested and the results were astonishing (less than 1dB variance between features - now 20 years later!). I’m unsure of this items left, right & band-to-band matching, but it’s been excellent in studio work having tolerances better than I can hear.

Build quality:
High attention to detail. 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, indicating the PSU regulation is working perfectly.

Impression:
I used this Intercity EQ in my studio for mastering a few projects (it was a spare unit for whenever I had a song with high stem count). This EQ, time and again, has shown itself superior to my digital EQ (Nebula, Sonnox, DMG EQuilibrium). The Intercity AEF1 has wide-band analog performance with a digital-like noise-floor. This level of EQ for room correction is a Hi-Fi investment that should last decades.

History:
As best I can tell, I am the second owner, it has been a spare unit and only seen light use in my studio. The Intercity is an undiscovered gem in the equalizer tree. Some Japanese music producers are familiar with it but it seems to be unknown in the west. These are best suited for flexible transparent speaker correction, room tuning, mixing and mastering.

Recommended users:
For existing and future audiophiles and studio owners.

Item condition:
It is in almost "very-good condition" due to the following caveat: the concert hall installers left small white marks (looks like little dots of white-out) on the B/W and Gain silk-screen indicators to show where the knob settings should be left at for that particular concert hall. I have not tried removing these marks as I don’t want to impact the silkscreen. These markings are not visible at 5ft distance (and I have good eye sight). FWIW, they aren’t bothersome up close. See photos.

Normally for a unit this rare and in this condition I would ask $4,000. In the past, Intercity sold this EQ as a Hi-Fi room correction solution for $9,000. Comparable units by GML are $4800 and $9000 respectively. Old 4band ITI/Sontec are going for upwards of $11,000, there is even one presently listed for $30,000. Anyway, I have discounted the price favorably.

Terms:
Item will be insured for the full amount. Signature required on delivery. International waybills will include the full item price (sorry). Return of a non-working unit or return due to description not matching the item delivered are allowed, otherwise all sales are final. I pride myself on transparency.

Included with the sale is:
A quality 117v to 100v step-down power supply (linear, quiet and regulated).

Being a speaker designer, audiophile and studio owner, I’m happy to spend time chatting with the new owner about acoustic treatments, room design, equalizer topologies, speaker alignments, whatever they fancy (sound technology is my life).

If you made it this far, then please see my other listings for more esoteric high-end kit.