Bent Audio Autoformer vs Tube Pre


Has anyone compared the two? I'm thinking of building a fully balanced Bent Autoformer unit.

If you have compared the two, what do you think?
128x128jtwrace
Well if you have the specs figured out and a balanced unit with remote is what your desire the Bent modules are going to be your best bet. In addition to a Lightspeed and Warpspeed (balanced) I built an autoformer volume control using the Slagleman units co-designed by John Chapman and Dave Slagle. All are very transparent and while I would give the nod to the LDR units for their increased transparency and purity in transferring the signal, building a balanced unit and one with a remote on top of it is not nearly as feasible.

I have considered building a balanced version using the Bent modules as well and may ultimately get around to it someday, but first I am having a custom direct coupled balanced preamp built that will serve as both a phono and tape head preamp with all the gain in that portion of the circuit and unity gain and buffered output in the linestage portion of the circuit. It will be interesting to compare this to the passive preamps I have.
I’ve had fun with both and I really think it comes down to system synergies and personal taste.

I’ve used a Bent TVC (S&B MK1 copper) for years and really enjoyed it. The sound is by far truer to the source and I love the remote control. My amps are not balanced so I can only take run from the DAC to the pre in balanced mode. When using the Bent I use a separate phone stage…

When I’m not using the Bent I use an Audible Illusions Mod 3b with the John Curl gold phone board. Overall I keep coming back to the AI just because it sounds so sweet with the rest of my gear. Yes there is coloration, and yes I don’t have anywhere the same control over the volume but it just works.

That being said I can’t bring myself to sell the Bent, and from time to time rotate into one of my stereos. I also defy all the odds and use 20 foot long interconnects from my preamp to the amps…

The main rig is as follows…
- Digital Sources: Levinson 360S DAC (fed from, Roku soundbridge, mac mini, Oppo 103, Levinson 17 transport)
- Analog Sources: VPI Aries, McIntoch MR 71
- Speakers: Marten Design – Dukes
- Amps: VTL Compact 100 (with NOS Mullard EL34 tubes)
- Cables: Crimson MusicLink (everywhere)
I still prefer the balanced tube preamp I'm using, which is more transparent with greater bandwidth (top and bottom) than the Bent, although the Bent is IMO excellent. My preamp has a direct-coupled vacuum-tube balanced output and can drive 100 foot cables with ease.