Thiel 3.5 equalizer advice

The midrange units on the 3.5's are paper, while they have a pretty large magnet, and are otherwise well built they do have a tendency to need rebuilding from time to time. Thiel is very good about this. Even if one wanted to use a a sub-woofer I'd recommend using the EQ and using the 40 Hz setting. If your not going to use the EQ, you might as well go with a smaller, cheaper Thiel that will actually go lower than a non-EQ'd 3.5. The EQ does put demands on the amplifier though. I think most of the objections to the EQ are based upon some sort of purist's prejudice. Of course one alternative is to put the EQ in a pre-amps tape loop and depending to the music, one could switch it and out. The only real down side, is an extra set of cables and having the signal passing through the pre-amps circuitry one more time. Once in a while you can find a used 3.5 EQ on e-bay, a much less expensive and less complicated alternative than adding a sub-woofer. The 3.5's EQ's stereo bass will be much better than a cheap sub-woofers.

Like Unsound said, be careful with midranges. I owned a pair of 3.5s and probably went through 4 midranges. The problem is that they use a first order crossover, that while yielding excellent phase linearity, burdens the midrange with having to deal with significant mid/upper bass energy due to the shallow slopes. Thiel was extremely helpful with providing replacement units, even after the speaker was out of warranty.

Keep in mind that the same cross-over philoshpy hasn't seemed to burden Thiel's other lines of speakers the same way. My 3.5's have only had their midrange drivers rebuilt once and they're over twenty years old. This was just a few years ago, Thiel did it gratis despite being well out of their ten year warranty. Kudos, Thiel!

I'm not sure if any of the drivers have been replaced, but it's good to know that Thiel stands behind the speakers so well. I will try the EQ this Spring and I like the option of putting the EQ in the tape loop. Thanks Unsound.

Using the Thiels without the EQ is like buying a Maserati simply to drive to and from the supermarket - you may enjoy the ride but you'll be missing out on what the overall intent was in designing it. I am currently "driving" my 3.5's with a Macintosh Mc275 tube amp which, for some people, may appear to be too little power for what are legendarily "power hungry" speakers. I listened with and without the EQ in line and I can testify that the EQ is necessary. It could be my ears alone which detected better imaging with the EQ in, but that's my story and I'm sticking to it. I love these speakers.