Ok, so I’ve had the tone-a-Matic on the SG for about two weeks. It’s a bit hard to assess because I was going from a bigsby with a roller bridge and I added a kluson JG stop bar at the same time - it’s solid brass and screwed down flush with the body. Even with the roller bridge - it cranked the sustain compared to the bigsby.
That being said - the addition of the tone-a-matic did change the frequency response considerably. Overall I would say that it just added “more” across the board, with a bit of a treble boost. The treble is most noticeable (as expected) on the bridge pickup. I actually use my tone knob now to tame it a bit!
At first I thought it was too much bite, but after playing a while with ts/muff/wah variations, I found myself creeping the knob back up and liking it.
The bottom line - I am very pleased with the added sustain and tonal response.
The tonal changes are all improvements and if necessary, easily tamed, but the major point for me was the ease of adjusting the height/intonation and then locking it in. It’s actually fun to set up the guitar - no profanity, no frustrating battles with thumb wheels - I got the action lower than ever and the notes are perfect up and down. (If you’re an SRV high-action type, that is only a few cranks of an Allen wrench away too.
This is a fantastic piece of technology in every way. I had known about this for some time, and I only regret not installing it sooner. There's a great article explaining in great detail many of it's technical advantages, which is here:
The info about the string pressure is especially revelatory.
First of all, the intonation range is out of this world. You really can use any gauge of string you like and still intonate properly. This is such an innovation. Yes, Nashvilles have greater range than ABR-1s, but this is far greater than a Nashville, far greater than anything I've seen.
Secondly, the tone blew me away. The sustain is wonderful on my guitar, even at the 22nd fret. This guitar came with a trem, and I had several dead spots, where, for a handful of notes, the note would immediately die and be replaced by a harmonic. It was maddening. Conventional wisdom places the fault for this in the neck and truss rod, but I found that when I switched to the Tone-a-matic, it completely eliminated the dead spots on my guitar, completely changing it's character from what I had viewed as a gimmicky limited run to a serious instrument, capable of real tone and real expression. It turns out the dead spots were entirely caused by the trem alone. Having been freed of this, I was inspired to drill a couple of extra pot holes, install a new neck pickup and switch to a Les Paul style control panel layout, when this thing came originally with just a master volume and tone control.
The installation was easy, and the locking nature of the bridge is crucial.
One word of advice: buy a low profile screwdriver to adjust intonation. It's easy not to consider this aspect until after installation, but the unbelievable range of travel of the saddles also means that there will be less room between the bridge and your tailpiece, so only a low profile screwdriver will fit.
The bridge locks, so it will not fall if you happen to remove all of your strings, and the area that locks the bridge to the studs also allows the entire bridge to be set further front or back from the studs, making the range of intonation even more incredible.
I had initial concerns that this would fit the stud and tailpiece holes that were drilled by Gibson to fit the trem that came on the guitar, and I wrote Hipshot before ordering. They wrote back to let me know it would be fine, and there were no issues with installation at all.
Be aware that these pieces may be built to order, so it may be a few days before they ship.
For my guitar, it utterly lifted the character, and took what had been mediocre at best to an absolute tone machine. Sustain is not the only factor in tone, but when you gain it for the first time in a particular guitar, you realize exactly how much had been missing. This bridge provided not only that, but really a mojo to the tone overall. I find it incredulously easy to go between very strat tones to very PAF tones on the fly. I'm thrilled with how the Tone-a-matic turned out, and I'm very grateful for the thoughtfulness that went into its design.