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What is a non-active pre-amp stage?? Are their advantages to this design??

I am considering an  Conrad Johnson CA-150 integrated amp which offers a "non active pre-amp stage"

Need and explanation of this design.  What are its pros and cons??  Does it provide better sound quality or performance, than an "active pre-amp stage" ?

Any comments about the C.J, CA-150 integrated amp sound quality??


Thank you,

S.J.



sunnyjim
sunnyjim OP
927 posts
 

To Steve, Thank you for the information.  Let me clarify. Will design affect volume of other components like a CD player or a turntable??  


The CA-150 has a remote (?) and so can I adjust the volume of all line level inputs with the remote from my chair??

Regards, S>J.

 

yogiboy's avatar
yogiboy
5,779 posts
 
You might not get enough volume using a phono preamp with a passive preamp. It all depends on the gain of the phono preamp and the output of the cartridge that you are using. The remote will work on all the sources that are being used!
williewonka
3,082 posts
 
@sunnyjim - Yogiboy might be right about the phono stage, but I have no problems with my Simaudio Moon phono stage which has an adjustable gain jumper in it.

Passive "pre-amps" only attenuate the signal. Sometimes they have an intermediate "booster amp stage" between the inputs and the actual  power amp section in order to provide the same overall abilities as amps with an active pre-amp.

If all of your components output the standard "line level" output voltage then everything should work fine.

The CA 150 does have a remote (as stated in the manual), so yes - you can do everything from your armchair.

Hope that helps - Steve



pragmasi
212 posts
 

I am considering an Conrad Johnson CA-150 integrated amp which offers a "non active pre-amp stage"

Need and explanation of this design. What are its pros and cons?? Does it provide better sound quality or performance, than an "active pre-amp stage" ?

From the look of the product page on their site this is an integrated amp by another name without input buffering before the attenuator... which is a pretty normal integrated amp design.

Personally I prefer to buffer the input to the attenuator (which makes it active), this allows the use of lower value resistors (800Ω instead of 10,000Ω) in the attenuator which means lower (johnson) noise levels.

I'm afraid I've not heard the amp in question so can't comment on that but it might be worth auditioning passive vs active if you can get a dealer to set that up for you.


georgehifi's avatar
georgehifi
10,312 posts
 
sunnyjim
What is a non-active pre-amp stage?? Are their advantages to this design??
jond
non active preamp stage means the preamp stage is passive

You heard of Nelson Pass no doubt (Pass Labs, Threshold ect ect)
This is what he said about passive volume controls, and yes he does make/ designs active preamps after all he is a business man.

Quote from Nelson Pass

We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.

Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.

Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.

What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp.


Cheers George
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