Those of you who had the good sense to read my book will see a picture of Altec 604 monitors, which were hanging in Phil Ramone’s mixing room when I schelped the Futterman OTL-1s in for his audition. We also used these speaker for a demonstration at the AES convention. These speakers, with all their flaws, set me on the path of rock and roll righteousness, with their alnico magnets and 100db effeciency.

Most Altec 604, like the classic JBL and Tannoy drivers now live in Japan, but I am sure you can locate them on one of the audio chat groups, and this may be the best, meaning cheapest, way to get your triode act together.

The speakers you want to get are the ones made between 1970 and 1980, and I believe   Altec still services these speakers, which means you can get diagraphms and speaker cones because thousands of these speaker are still in use at radio stations and recording studios.

Those who need the right speaker for their OTL or single-ended triode should consider these speakers with the following caveat...

Altec 604 have a major frequency anomoly between 2 and 4KHZ, and the stock crossover doesn’t deal with it. The old Doug Sax Mastering Lab crossover was the fix, but these are very hard to find.

With computer programs and speaker nerds multiplying it should be a no brainer to figure out the right notch filters, and there must be some one out their on the audio web who knows what to do.

The other key to the puzzle is the building the right cabinets. Altec published cabinet plans for this speaker, but again... find out their electrical parameters and use one of the new loudspeaker design program which will give you optimimum box size for the frequency/alignment you want.

But the really great news for those who are into digital is the use of the new digital preamps, like the NAD, which will permit you to mollify the weirdness of the speaker in the digital domain.

I have seen these drivers advertised for as little as $500 per pair, which is less than the cost of a pair of Western Electric 300Bs, and the extra effort you put into these speakers still means that you have saved thousands of dollars and...you finally have healed your pain....you will be listening with 100db/alnico speakers.

So let me close with a simple real life example: I listened to the new Cary 2A3 amplifier at my friends house who had moderatly effecient speakers and this 3 watt amplifier sound very bleak indeed. When I took it home and listened to it on my Tannoy horns I couldn’t turn the volume put past 9AM...if you want to the mystery of directly heated triodes you need speakers like the Altect 604.



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