If you have any questions or comments concerning the
EICO HF-81, please drop me an email:

dedicated to one of the finest sounding integrated amplifiers made 
home system mods rebuild super hf-81 links

Mods & Ideas
Kelly Holsten ~ Jean-Francois Lessard (shots in right column click to FULL SIZE)

: It's now August of 2007 and everything is still "coming soon." My apologies to all that are waiting. I attempted to answer all the email and will try to update this page sometime in the near future. Can you get any more nebulous than that?

Tone Control Bypass
Many have wondered how the EICO would sound without the tone control compromise in the circuit. This mod below, outlined by Jean-Francois Lessard, does bypass ONE HALF of the 12AU7 stage but the tone controls are out of circuit.  You need to be the judge whether you think the mod beneficial. It might just sound better, tone circuit left intact
. > Tone Control Bypass

Balance Pot Bypass
The Balance, or FOCUS, as it's known on the HF-81, is a pretty mediocre pot and strangely enough, seems to be wired wrong in a few units I've heard.  Bypass the whole affair if you desire
- Coming Soon

The Humming Buzzing Power Trans
The Eico HF-81 power transformer has always been a slightly weaker affair.  It seems to be problematic in quite a few of the units with many samples bringing hum and buzz after years.  It gets extremely hot and sometimes the wax has seen better days.  Solution?  Heyboer Transformers makes a great replacement.  It's a recommended mod for any suffering from the EICO PS Trans Blues (or buzz as it were) -
coming soon

The Power Switch Failure Solution
Almost every EICO HF-81 I know finally succumbs to the dreaded power switch failure.  It's embedded in the treble control so it's not an easy fix to keep stock.  Many have bastardized their HF-81 with holes for a new unsightly switch.  Here's a neat solution that makes the most sense and is not visible to boot
- Coming Soon

Cap and Resistor Choice:
How to keep the HF-81 Magic Intact

Although the Super Eico HF-81 has been the subject of debate, it's becoming somewhat evident that some of the magic and quality of the original HF-81 does not come out in the wash.  It seems the modern HF-81 with trimmed down circuit and hi-po parts might reap some rewards but at a loss of others.  The same can be said for an all-out mod of the original.  Just what is the best selection of parts to avoid changing the entire character of the amp? 
- Coming Soon

The EICO HF-81 Phono Stage:
Any Improvements to make this quiet?

While the HF-81 is known for its sonics via the line stage, not much is said about the phono section.  There seems to be a universal problem with some residual hum out of the left channel. Many use an outboard phono stage including myself.  Can the little HF-81 phono be brought to a better light?  > Phono Stage Mods

If you have any questions or comments concerning the EICO-HF-81, please drop me an email:



Someone followed the site on this one
Possibly one of the cleanest HF-81 around

Mod Galore w/Phono - Auricap~Kiwame-Atoms etc

Eico in main system for vintage soul

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