[jnorris]

   
Sounds like you need a B1 buffer.  Designed by Nelson Pass himself:
 
https://www.passdiy.com/project/preamplifiers/b1-buffer-preamp
 
I just got mine up and running and agree with Dick Olsher's assessment that it is like a Windex treatment for your sound system:
 
http://www.enjoythemusic.com/magazine/equipment/0708/first_watt_b1_preamplifier.htm
 
One caution though - you will hear every flaw in your system!

 
I've been around the block a few times on this subject with a number of systems and my conclusion is always the same:  the insertion of an active stage degrades the signal.  It may be a harmonious degradation such as expanded dynamics or enhanced equalization, or it may be just a closing down of space and depth, but it is still degradation.

 

[SpeakerBox]

   
I've been around the block a few times on this subject with a number of systems and my conclusion is always the same:  the insertion of an active stage degrades the signal.  It may be a harmonious degradation such as expanded dynamics or enhanced equalization, or it may be just a closing down of space and depth, but it is still degradation.

 
Agree 100%.  Technically the B1 is active, has a gain of one, and provides impedance matching - so even that may not be to your liking.

 

[JamesBr]

   

I've been around the block a few times on this subject with a number of systems and my conclusion is always the same:  the insertion of an active stage degrades the signal.  It may be a harmonious degradation such as expanded dynamics or enhanced equalization, or it may be just a closing down of space and depth, but it is still degradation.

 
True!Like you said for me if its harmonious its ok but technicaly you are right that it is still a degradation

 

[MermaidMan]

I just picked up a Fisher RS 1020 from a thrift store. Everything seemed to work fine in the store but I could only test if the headphone out worked with a cheap pair of old headphones they had laying in the store. Since I will be away from my cans for a few days, can anyone comment on what i should expect performance-wise? I paid $30 and it was in fair cosmetic shape, but i cleaned it up a good amount.  

 

[Mechans1]

   
True!Like you said for me if its harmonious its ok but technicaly you are right that it is still a degradation

If  degradation means any change to the signal then yes, but I think of degrading as taking something good away from the signal.  Therefore I would not consider any and every change degrading, I guess that is obvious forgive me.

 

[Silent One]

 
It was local to me. We missed it by an hour I think. I emailed the guy when I saw it and someone was on his way to pick it up - 3-400 miles too. Shame since it was only $2000ish.

That we missed it by an hour had me kickin' cans up and down the street like a school kid cuttin' class..."Now what?"

 

[Mechans1]

Something will show up.  Maybe not instantly but down the road. I have noted that there is a revival of some sort for that kind of gear.  Wait for a that  good deal to show up.

 

[KeithEmo]

  I've been running without an active preamp stage on my main stereo for decades.  I was using a hollowed-out Hafler DH-101 which was basically a source switcher with a volume control.  Now I've got a Sumo Athena preamp that allows for the removal of the gain stage.  Whenever I insert an active preamp I can hear the degradation. 

 
Quite true - however you have to consider the possibility that, in at least some specific situations (such as where you have long cables to drive or the next item in the signal chain has a low or variable input impedance), not adding an active stage can result in even more signal degradation than adding one. One common example is "passive preamps" (a volume control). By inserting a potentiometer in the signal path, the source impedance seen by the next device - and the interconnecting cables leading to it - is raised. This can result in more hum and noise being introduced than would be by an active gain stage. To be strictly accurate, almost anything can introduce noise or distortion.
 
I recall reading an article a very long time ago about a modification on a Dynaco power amplifier (remember those?) The modification entailed adding a switch that could be used to bypass one of the gain stages. However, when the modification was actually tested, it was found that the contact resistance of the switch actually produced measurably MORE distortion than the transistor gain stage it was bypassing. (The distortion was very low either way, but bypassing the active stage made it worse rather than better.)

 

[buson160man]

Dynaco  Oh that brings back memories. I used to own a dynaco sca35 integrated amp. I believe it had a passive preamp stage. Mine was rebuilt with much better parts, It actually sounded pretty decent . I used to call it my pocket battleship amp. I remember taking it over to friends houses who were using  receivers and amazing them when they heard the dynaco which clearly sounded better than most of the receivers at the time. Alas my dynaco was stolen from me by a person I lent it to (obviously I did not know that person  as well as I thought) . He did not return my unit and moved A lesson well learned . I really liked that dyna unit oh well one of lifes lessons.

 

[DaemonSire]

What would a good price be for a Pioneer SX-780?  From the pictures, it looks like it is in very good physical condition.  Unfortunately I am not close to it so will need to have it shipped.
 
The seller has a lot of positive feedback so no issues there.
 
He said that it works great.  1 channel needed to be repaired and the bulbs were replaced.
 
Thanks!

 

[SpeakerBox]

  What would a good price be for a Pioneer SX-780?  From the pictures, it looks like it is in very good physical condition.  Unfortunately I am not close to it so will need to have it shipped.
 
The seller has a lot of positive feedback so no issues there.
 
He said that it works great.  1 channel needed to be repaired and the bulbs were replaced.
 
Thanks!

 
I would say in the two to three hundred range.  With $250 being the sweet spot for a nice one.

 

[ssrock64]

   
I would say in the two to three hundred range.  With $250 being the sweet spot for a nice one.

I would agree with that, though the whole market is always creeping up in value.

 

[Skylab]

For $250, an SX-780 better be in great cosmetic shape and work perfectly. They can be had for less, for sure. And if you can find one, either a 880 or 980 is a significant step up in build quality.

 

[DaemonSire]

Thanks for the advice everyone, that helps.
 
Follow-up:  Any experience using it to drive the HE-6?  I plan on eventually getting the HE-6 and would like to use a vintage amp to drive it.

 

[Oregonian]

For $250, an SX-780 better be in great cosmetic shape and work perfectly. They can be had for less, for sure. And if you can find one, either a 880 or 980 is a significant step up in build quality.

Agreed.  Just saw this morning a SX-750 on CL for $75 that needed nothing.................almost tempted to buy it just because.