Passive Preamps

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#1
Anyone use or have opinions about passive preamps? Trying to learn about them. Thank you.
 

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#2
I'd be worried about getting enough pre out to fully drive the amp (when needed), that is, getting full line level to the amp. Might not be an issue though.
 
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#3
I'd be worried about getting enough pre out to fully drive the amp (when needed), that is, getting full line level to the amp. Might not be an issue though.
Thank you, something to look into deeper maybe? This site is the greatest thanks to all the help.
 

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#4
Do you have any examples you are interested in so we can look them up and perhaps provide opinions?
 
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#5
Do you have any examples you are interested in so we can look them up and perhaps provide opinions?
This is the one that got me started and wondering about them https://www.ebay.com/itm/Vintage-Purset-Sound-System-PSS-by-David-Hum-Passive-Preamp-Out/312796748958?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649. Also https://www.bellariaudio.com/index.php/products/pp532-passive-preamplifier/. I'm just always trying to learn about other options. Thinking that the clearer and cleaner the signal that's sent to the power amp, the better.Thank you.
 
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WOPL Sniffer

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#7
Let me know what the consensus is on the phono side of things. The levels on MC can be pretty low too
 

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#8
from what I have been reading, getting a unit with impedance matching circuitry is important for the sound. Now, finding the right Passive Preamp to set right with your system sounds to be a pain in the ass and maybe expensive too. What sounds good on yours, may not cut it on mine but aint that the way Actives work too??? We'll have to wait for the smart guys to chime in. I'm way happy with the state of sound with my pre so....
 

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Oh, and forget about the dude designing and building their own Passives.... They will think their's sounds 10 times better than an active and with the sound of an audio system being subjective and inversely proportional to your hearing loss...... HUH???
 
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#10
from what I have been reading, getting a unit with impedance matching circuitry is important for the sound. Now, finding the right Passive Preamp to set right with your system sounds to be a pain in the ass and maybe expensive too. What sounds good on yours, may not cut it on mine but aint that the way Actives work too??? We'll have to wait for the smart guys to chime in. I'm way happy with the state of sound with my pre so....
Me too, but it might be an interesting thing to play with.
 

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#11
If all your sources are very high level, then you can probably get away with a passive pre. The power amp you feed with this typically has ~47K input impedance. Not sure what resistance pot they use in these but unless very low in value will interact with the input impedance of the power amp.

Typical active preamps deliver a very low output impedance to be able to drive just about any power amp.

Yes Fred, Hum is a bad name for anything audio.
 
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Oh, and forget about the dude designing and building their own Passives.... They will think their's sounds 10 times better than an active and with the sound of an audio system being subjective and inversely proportional to your hearing loss...... HUH???
Yep, I "hear" that one.
 

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#13
Unless I am missing something, a "passive preamplifier" is an oxymoron. There is no amplification, pre, or otherwise. These units are switch boxes with volume controls. I think it would be better to add a volume control to your amplifier similar to the way Phase Linear did on the 700B model.
For switching, you could pull on the pair of RCA cables and plug them into something else.
They used to have these in stereo stores, they were called "Selector Panels" for auditioning the various stereo units or speakers.
 

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#14
Well, I know this much.... I use my Ipod straight into my WOPLs when doing initial testing on the bench and it sounds like crap without a pre......
 

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#17
I have a Superphon SP100 - it's a buffered passive preamp, so it does have a power cord. I traded a VERY good Yamaha integrated amp for it, and am currently using it between my Bluray player and my power amp. It is simply because the TV's internal speakers are going bad, and yeah, I want that BASS! My main system uses a tubed, one-input, one-output, no tine controls preamp, powered by eight "C" cells. It's very quiet. I like it better in some way than the passive.
 

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I have a Superphon SP100 - it's a buffered passive preamp, so it does have a power cord. I traded a VERY good Yamaha integrated amp for it, and am currently using it between my Bluray player and my power amp. It is simply because the TV's internal speakers are going bad, and yeah, I want that BASS! My main system uses a tubed, one-input, one-output, no tine controls preamp, powered by eight "C" cells. It's very quiet. I like it better in some way than the passive.
Laz, "Tine Control"???
 

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#19
after reading that several times, I assume you mean no Tone Control???

I'll skip the battery powered stuff though (except for vibrators).... They should not plug into the wall. You could trip and hurt yourself.

HUH?
 

Lazarus Short

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#20
Yes, tone control. As you get older, it's the vowels that get confused first...

I tried the stock wallwart: HUM. I tried every other wallwart that I could use on the preamp: HUM. Then I went to batteries.
 
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