Placette passive preamp?

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sleepysurf

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Anybody who's used/using the Placette passive linestage/preamp? Although I love the "midrange warmth" of my Modwright, I've noticed that running my Benchmark DAC direct to amp (or via my Denon 3808), gives a more detailed low end. I need remote control and Home Theater Bypass (which the Placette can be custom ordered with) and am curious if the sonic benefits of the Placette might be worth a try. I'm not particularly knowledgeable about impedance matching issues, but as best I can tell, my Benchmark DAC-1 (30 Ohms output impedance) and Belles amp (50,000 Ohms input impedance) should theoretically work well with the Placette, especially using my short (18") interconnects. Might I end up losing dynamics, musicality, or something else?
 
I have not heard the Placette so I can only comment from the general perspective of someone who loves passives. Like you said, the output/input impedance ratio of your DAC/Belles looks healthy. An uncertainty remains about output/input sensitivity i.e. does the DAC-1 output have enough voltage to drive the Belles to full scale. If yes or close then I would have no concern re. dynamics.

Have you considered the CIA PLC-1? Of course as an owner I am completely biased but I think that it is a lot more practical and probably cheaper too. HT bypass is standard, as are tape loop and the most tactile volume remote control you've ever touched. It also has dual pre-outs if you ever want Descent Summits for stereo.

As for the difference between stepped fixed-value resistors (Placette) and pot (PLC-1): the latter is an ultra high precision Alps pot. L/R channel balance is guarantueed to be better than 60dB.

As for losing musicality: perhaps. This would of course depend on your tastes. But if you do lose "musicality" you would at least gain truth. :)
 
As for the difference between stepped fixed-value resistors (Placette) and pot (PLC-1): the latter is an ultra high precision Alps pot. L/R channel balance is guarantueed to be better than 60dB.
I replaced the ALPS pot in my preamp with a DACT stepped attenuator, and it made a HUGE difference (improvement). The pot was a garden-variety ALPS though; I did not realize that ALPS also made an ultra-high precision one.
 
Thanks for the heads up on CIA. I didn't even know Dusty offered that product! In fact, the VPC-3, with dual inputs, might even fit the bill, since my Squeezebox accounts for 95% of my listening, and the extra overhead bits allows adequate volume control without loss of fidelity. Too bad he doesn't offer them with a black faceplate! :mad:
 
Just spoke with Dusty, and ordered the VPC-3! It uses the same high-precision Alps pot, just not motorized. I only need two inputs, and can't go wrong for $299, with 30 day money back (minus 10% restocking).

I actually spoke with Dusty a loooong time ago, when I was contemplating the D-200 monoblocks. I'd heard good things about them, but eventually went the non Class D route. It looks like you've replaced them in your setup??
 
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Bernard, my first passive was a VPC-2, a predecessor of the current VPC-3. One of the main upgrades in the VPC-3 is the better Alps pot which it shares with the PLC-1. The VPC-2 is fine at volumes beyond 10 - 11 o'clock. Below that the PLC-1 (and therefore the VPC-3) is much much better indeed.
 
Well Alan, that did not take you long now, didn't it :). And what a good choice!

The VPC-3 is probably the best line stage available for $300 if sources and amp are compatible with the requirements of a passive pre.

A stock SB3 can drive my amps to full scale and so can the CIA DAC I'm using. I'd be very surprised if the DAC-1 could not. This should be a good match.

As for the D-200s: no, I did not replace them.

It is true that I love the Emotiva RPA-1. (I believe this is the amp you were referring to re. replacements.) The RPA-1 is an amazing amp not just within its price bracket but well above it. Neutral like the D-200s and very similar sounding overall but less that 1/3rd of the price. Since I bought the RPA-1 on a sale it cost me less than 1/4 or the D-200s!

Originally I bought it for a second system which I have yet to build. Since it performs so well I have been using it in my main system quite a bit. That much performance for so little money is fascinating. But replacing the D-200s it can not. The RPA-1 reminds me of a KAV-2250, punchy, clean, fast, detailed, but also a little lean. The D200 sound has the same attributes but seems to reproduce overtones in a more believable way. Hard to describe without using cliches. Overall I enjoy the music more.
 
Bernard, my first passive was a VPC-2, a predecessor of the current VPC-3. One of the main upgrades in the VPC-3 is the better Alps pot which it shares with the PLC-1. The VPC-2 is fine at volumes beyond 10 - 11 o'clock. Below that the PLC-1 (and therefore the VPC-3) is much much better indeed.
I first replaced my cheap ALPS pot with the highly-rated TKD at $62; it sounded much better, but I messed up the pot by applying a bit too much heat when soldering it into the circuit (it is ridiculously heat-sensitive. So I bought the DACT instead ($190); it was MUCH better than the ALPS and the TKD. If I were a betting man I would bet you the price of the DACT that if you bought the VPC-3 and replaced the ALPS with the DACT it would sound much better. BUT......I'm not a betting man :(
 
Listen carefully - that's my advice. There are a lot of peopole using passive preamps, so you can't argue with that.

That being the case, I don't like any I've heard - they seem to make the system lose that "drive" and punch. That authority that I like seems to disappear.

Of course, the success of a passive pre would be highly dependant on your source and amplifier synergy so your results may well vary.
 
Like most things audio-related, system synergy reigns supreme! If the VPC-3 gives me the detail/resolution I'm seeking, great! If not, I'm only out < $40. I greatly appreciate and respect companies like CIAudio, who let you "try before you buy". I only wish there were more like Rusty out there!
 
I use an Adcom GFP-750 and would not trade it for anything I have heard so far...I auditioned it against all the various high $$$ preamps including MAC's, ML,Conrad Johnson, Halcro, AR....passives are cleaner but only work with short cables and I rec you go xlr....if you want tube like midrange stay with tubes. I am biased as I tend to gravitate to more sterile/pro equipment ie: Bryston amp+ Benchmark DAC+ Tascam reel to reel.
 
The conundrum is solved!

As posted here (and elsewhere), my Modwright SWL 9.0SE had become increasingly "flat" sounding lately, even after replacing the stock Sovtek 5AR4 rectifier tube with a NOS Mullard (bought on eBay). Bypassing the linestage altogether (running Benchmark direct to amp) brought back the bass and treble "zing" and overall musicality, so I thought I just needed a pure SS path for musical nirvana. I bought the CIAudio VPC-3, but before I could even compare it head-to-head, my Modwright suddenly sputtered while powering up, and the rectifier tube socket sparked, then the fuse blew. Fearing the worst, I sent it back to Dan, thinking I blew out the power supply. In the meantime, I put the VPC-3 to work, and found this "minimalist" approach sounded very good. Bass was tight, vocals and treble very clean, but the entire presentation was still lacking something.

Meanwhile, Dan carried out some bench (and listening) tests on my unit, and reported back that everything was up to snuff, and the problem was merely a bad Sovtek rectifier tube. In fact, he said the Sovtek 5AR4's have proven so unreliable, that he has stopped using them. He shipped the unit back to me (at his expense!) and included a new Ruby 5AR4 (chinese, but very reliable). Upon firing it up, I was aghast to hear all sorts of background hiss, with even more snaps, crackles, and pops than before! Bewildered, I pulled out all the tubes, cleaned the pins, and made sure they were firmly seated. Firing it up once again... VOILA... music to my ears!! Dead silent background, and the bass, midrange, and treble were like nothing I've ever heard... frankly, much better than the original Sovtek and my (supposedly NOS) eBay sourced Mullard, which is apparently a dud! Even my wife perked up and commented that the music sounded so real!

I'm not sure how long my Modwright was firing on less than all cylinders, but WOW, what a difference working tubes make! Kudos to Dan for superb customer service, and for making sure that anything with the Modwright moniker lives up to expectations! The VPC-3 is a great passive pre/switch, and I'll probably hang on to it. However, for sheer musicality, with guts and soul, nothing beats my Modwright (except, of course, the Modwright LS 36.5, which I''l, perhaps, be lucky enough to get some day).
 
If you want to get even more of that, get your hands on a Sophia Electric 274B
or if you really want to get wacky, a Western Electric 274B....

Expensive but worth it!
 
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