Author Topic: Passive Preamp?  (Read 16476 times)

Offline Reverend

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Passive Preamp?
« on: January 27, 2015, 11:38:19 AM »
Is anyone using or have used a passive preamplifier?  I bought a little Schiit passive and I'm running it with my baby carver tube amp and love the sound.  No coloration, gain, etc.  I'm mulling over trying this in my main system and would like your input.  I've read/heard repeatedly about having to use short interconnects/etc.  As a test I ran 1m cables from the source > pre > amp vs. 2m cables.  I couldn't tell any difference and really, I don't have any interconnects over 1.5m so it's not a concern.  I'd love to hear your opinions.

bearjew

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Re: Passive Preamp?
« Reply #1 on: January 27, 2015, 12:42:34 PM »
If you do set that up, let me know, I'd be interested to hear it.  I'm not surprised that it sounds good, being that I've heard two Schiit pieces, and they're awesome.  I will be surprised if you end up liking this more than the Melos though, primarily because of price point (it just doesn't seem like the Schiit was designed to be as good as or even compete with something high end), but if any company would prove that whole thing wrong, it would not surprise me if it was Schiit.

Offline ataudio

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Re: Passive Preamp?
« Reply #2 on: January 27, 2015, 12:48:44 PM »
Oh boy....from capacitors to passive preamps.  We are stirring the pot hard this week  >:D >:D >:D
(Please note the devil smiley)

Rev...I love passive preamps.  Using a DIY  version now.  Zero noise floor. Properly implemented completely
transparent. Excellent macro/micro dynamics.  It all comes down to two variables (IMO).
The volume control and switching method.

POTs: I've used carbon, cermet, vintage ,new, ALPS, Noble, generic
And the very best sound pot ever (again, to me) is a Spectrol 10 turn wirewound pot.  Transparent all the way.
Forget about carbon, sprayed conductive plastic, etc. They all pale in comparison.

Best switching circuits is two dpdt center off switches...gives you four inputs and very easy to wire up.
And I suspect much better surface area/contact force over a rotary switch. 

I have an ElectraPrint PVA passive in the works now.  Have all the parts but need to assemble it.
From my breadboard testing its superb as an inexpensive passive.  Certainly a worthy contender until I find
A tube preamp I like.  You're going to find most folks will slam a passive. They just don't have mass appeal.
Use your own ears and you decide.  I've used them on/off for decades. Out of all the versions I've built I've only had issues with one transformer based unit and tuners.  Several mid fi tuners just wouldn't work with input impedence of the transformers used at that time.  CD players have all been extremely successful.  Never an issue there.  They must have more robust output circuits. 

Again..passive aren't popular. Many hate them w/o ever hearing one.  Some just can't get past the idea of turning the volume control beyond 12 o'clock...like its some mental barrier. Trust your own ears and keep an open mind/ear.

Offline RuralTom

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Re: Passive Preamp?
« Reply #3 on: January 27, 2015, 01:42:37 PM »
I've been switching back and forth between my two main preamps for a month now, one of which is the Schiit SYS.  I haven't had any issues with sound degradation due to cable length, even with the 2m cable I run from the SYS out to monoblocks on separate sides of the room.  No issues from the sources I've used either, my DAC, turntable and CDP.

I do think the passive sounds a bit better than the active,as ataudio states a move towards better transparency and dynamics, but lean towards using active of late.  I run the SYS wide open and use an iPod for volume control, but the convenience of the active -between the remote, more inputs(and outputs), etc- seems to win out. 
preamp: BAT VK-5
amp: Altec 944sa
DAC:  Bel Canto 2.5
CDP: Pioneer Elite DV-47a
Intel NUC server / iFi micro iUSB3.0 / Roon
Spendor FL9

Offline Reverend

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Re: Passive Preamp?
« Reply #4 on: January 27, 2015, 02:05:29 PM »
Thanks for your input guys.  Yeah the Schiit SYS is what I've been playing around with.  I just really liked the non-colorized tone with the mini carver.  I will try the little SYS in the main system and see what happens.  Unlike some others on the forum, I feel like I can hear differences in anything and price point is not something i really take into account even though I like to bust OBG balls about it.  Mainly because he's a cheap bastard.   :laugh:

I'm looking at a "high-end" passive right now that I might be able to pick up on the cheap.  I don't have any immediate intentions to get rid of my Melos, it's still one of the best pre's I've heard in combination with my setup.  Tube dual mono pre w/ giant external power supply vs. a Passive.  You can't get two more different  pieces of equipment then that.  Should be fun experiment.







Offline ataudio

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Re: Passive Preamp?
« Reply #6 on: January 27, 2015, 02:41:21 PM »
Definitely keep us posted.  Would love to hear which passive you get and its pros/cons.
I hope to get a  TVC passive someday.  Good luck...let us know.

And if you decide to sell the passive give us first shot ;)

Offline RuralTom

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Re: Passive Preamp?
« Reply #7 on: January 27, 2015, 03:13:42 PM »
Definitely keep us posted.  Would love to hear which passive you get and its pros/cons.
I hope to get a  TVC passive someday.  Good luck...let us know.

And if you decide to sell the passive give us first shot ;)

Too bad, I saw a 'standard' Prometheus at a shop in Portland, but didn't realize how what a good deal it was.
preamp: BAT VK-5
amp: Altec 944sa
DAC:  Bel Canto 2.5
CDP: Pioneer Elite DV-47a
Intel NUC server / iFi micro iUSB3.0 / Roon
Spendor FL9

Offline geoffr

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Re: Passive Preamp?
« Reply #8 on: January 27, 2015, 04:31:48 PM »
I've been using a Creek OBH-12 passive pre with a Belles One amp for years, with a number of speakers, in a number of locations. Right now it's in my woodshop. I have always enjoyed the sound - it seems to be a great match for the Belles and,  as a bonus, has a remote.
Living room: Fisher 400, Thorens TD124, Arcam CD, Klipsch Heresy
Home office: Scott 222c or Fisher KX-200, Thorens TD124, Marantz CD + Peachtree DAC, Omega 3T desktop speakers and Deep Hemp sub
Basement: Rogue Cronus, Meadowlark Kestrel, Rega P25, Marantz CD

Offline Sir Thrift-a-Lot

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Re: Passive Preamp?
« Reply #9 on: January 27, 2015, 08:13:35 PM »
I've never heard a passive pre.   The lack of a tape out has kept me from seriously exploring it.   Sorry I can not be any help.

Offline geoffr

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Re: Passive Preamp?
« Reply #10 on: January 27, 2015, 08:33:20 PM »
I've never heard a passive pre.   The lack of a tape out has kept me from seriously exploring it.   Sorry I can not be any help.
My Creek OBH-12 has a tape loop:
http://img.ukaudiomart.com/uploads/large/119422-creek_obh12.jpg
Living room: Fisher 400, Thorens TD124, Arcam CD, Klipsch Heresy
Home office: Scott 222c or Fisher KX-200, Thorens TD124, Marantz CD + Peachtree DAC, Omega 3T desktop speakers and Deep Hemp sub
Basement: Rogue Cronus, Meadowlark Kestrel, Rega P25, Marantz CD

Offline MacGeek

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Re: Passive Preamp?
« Reply #11 on: January 27, 2015, 08:48:27 PM »
Mac stuff, Sony HDR-F1HD AM/FM/HD tuner, Denon DRS 810 cassette, Denon CDR-W1500 CD recorder, Music Hall MMF-9 w/B&O MMC2, B & O 4002 w/B & O 20 CL, Revox A-77

Offline geoffr

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Re: Passive Preamp?
« Reply #12 on: January 27, 2015, 09:00:55 PM »

My Creek OBH-12 has a tape loop:
http://img.ukaudiomart.com/uploads/large/119422-creek_obh12.jpg

What does the power supply do for a passive pre?

It is only for the motor for the remote controlled volume pot. It works manually without being plugged in.

This is the passive pre I want to try:

http://www.amazon.com/Emotiva-Control-Freak-Unbalanced-Passive/dp/B00JRHUGDI/ref=sr_1_1?ie=UTF8&qid=1422387172&sr=8-1&keywords=emotiva+volume+control&pebp=1422387174245&peasin=B00JRHUGDI8)

Too bad it doesn't have a ganged volume control to allow balance adjustments.
[/quote]
Living room: Fisher 400, Thorens TD124, Arcam CD, Klipsch Heresy
Home office: Scott 222c or Fisher KX-200, Thorens TD124, Marantz CD + Peachtree DAC, Omega 3T desktop speakers and Deep Hemp sub
Basement: Rogue Cronus, Meadowlark Kestrel, Rega P25, Marantz CD

Offline MacGeek

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Re: Passive Preamp?
« Reply #13 on: January 27, 2015, 09:05:41 PM »
Of course, thanks.
Mac stuff, Sony HDR-F1HD AM/FM/HD tuner, Denon DRS 810 cassette, Denon CDR-W1500 CD recorder, Music Hall MMF-9 w/B&O MMC2, B & O 4002 w/B & O 20 CL, Revox A-77

Offline Reverend

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Re: Passive Preamp?
« Reply #14 on: January 28, 2015, 09:46:25 AM »
Last night for Schiits and giggles I put the SYS into the main system.  I connected my mac mini > DAC to the pre.  I sat down thinking, there's no way this little $50 box is going to sound any good.  I was wrong, I played one song and was amazed at how much the noise floor dropped.  The harshness of the ribbons was completely gone but the imaging was still just as good if not better with a wider presence.

Pepe swung over a little later and I had him sit in the listening chair.  After awhile I asked him if it sounded better not telling him what I had done.  He could tell right away that something had changed and that the ribbon harshness, my system has an issue with, was gone.

Pros:  Smooth sound, much lower noise floor, a more natural imaging, greater dynamics and it really let the source and amps shine.

Cons:  This really has to do with the Schiit SYS; it's a good little box but you could tell some mid dynamics were missing.  This should easily be fixed by either purchasing a higher end passive pre or building a DIY one with better connections/pot/wiring. 
« Last Edit: January 29, 2015, 12:40:24 PM by OldiesButGoodies »