Passive Pre - No Regrets?

Actually, I have compared autoformer vs TVC. It's really simple when you wire your own. Just use one side. To be honest, it was a mistake and was supposed to be a mute switch. Being a switch, I could compare instantly. I thought the difference between the two was almost negligable. The autoformer did have a slight advantage in the bass but the ability to use both RCA and XLR inputs swung the vote to TVC.

I've also had the opportunity to compare silver versus copper windings with a friend's TVC. Silver worked better with tube amps and soft domes but I preferred the copper with SS and ribbon tweeters. Odd, since I've always favoured silver or silver plated IC's.

Over the years, I have also tried passive pots and attenuators in various configurations but I haven't tried the Placette. There was a big difference between pots I tried and a simple resistor in line. Don't ask me why. I have never directly compared the attenuator to the TVC.

The Placette has arrived. I don't and won't rush to judgement - I plan to A/B with the CAT for 2-3 weeks. I can say that it is certainly competitive, and on first blush I think it might be better. I do not notice any diminishment in bass or dynamics which I was looking for. It is quiet. The music seems to be very clear and localized - that is I hear clear delineation between the location and source of a sound. Microdymamics are fantastic, instrumental or vocal inflections (what I think expresses emotion)is superb. I impressed that at this point I can't say the CAT is better, a pretty good sign for a $1000 unit - true, there is no switching facilities and can't drive long, high capacitance cables - but you know, you could defintely live with this thing in a high end, single source system. To say the least I am impressed. I would certainly recommend that this piece be auditioned and compared with top of the line active preamps (the CAT has to be one of the better ones). It is making me awfully interested in hearing Placette's no-gain active - I think Placette's desinger is on to something, and it might be that Vishay-based volume control . Well, I'm going to listen to this for a while, but darn it sure has made a good first impression.

Well I be Darn..Mikey I think he likes it!!! LOL

Good for you..have fun!!

The issue of DC on an output would not be solved by any of these controls, but I should nave been more clear. My point was that even though DC on an output would be a problem for an autoformer, this didn't strike me as a real life problem since resistor based volume controls would have the same issues. In the first place there shouldn't be any DC on the output of a commercial source since many amps are DC coupled and it would cause severe problems. If you are doing DIY like me then it is something you have to decide for yourself.

In any case a transformer would also be a bad choice for a source with DC sitting on it's output. The way to do it (as mentioned) is a cap to block the DC. A transformer would short it to ground, not good. There are some designs such as either a parafeed output or an interstage transformwer acting as a plate load with a tapped secondary that would do double duty; DC isolation and volume control, but then you have to worry about the varying load on the output tube as you change the volume.

Nothing is simple it seems.

"Still waiting, but maybe they'll arrive today. Atmasphere. let me ask you a question. If you could design a passive preamp, choose an appropriate source with just the right output impedance, select the cabling to be used (for appropriate electrical properties- and lenght)and they were feeding one of your OTLs or some other quality 100KOhm load - that is you could optimze the variables that determine successful versus unsuccessful implementation of the passive approach - could you conceive that a passive, minalmist approach might work better, sound better than an active, any active preamplifier. I would accept that the passive might not be as flexible, be more fussy, and may be less universally marketable."

Here's the problem that passives are up against (if done my way). 'My way' is to eliminate the interconnect cable as a sonic variable so that any cable will work as well as any other (right now you have to go balanced to do that BTW).

Anyway, to achieve the above for me would mean a very low resistance passive system- probably about 100 ohm control would do the job. This is a challenging impedance for a CD player to drive with low distortion and enough voltage to drive the power amp. Please keep in mind that I am expecting the system to be immune to the effects of the cable. You are not going to get this if the value of the passive is much higher than that. IOW, its impractical with current CD players and phono sections.