I wouldn't give up my Sansui for a 1980, let alone a 1250.

A few pages ago I was gutted because I'd found my dream sound when I fell for an amp called the Sansui AU-505. But if you remember she had a slight hummm... Hmmm it was doing my head in. Anyways, I just picked up a pair of K701's today (my third set over the years..) and to my surprise when I plugged them into the 505, no hum whatsoever :O Its as quiet as church mouse who's on a mission not to make any noise at all.
They are a strange headphone indeed the K's with their impedance swings. I remember them being more power hungry than my LCD2's and even HE500's. However, vintage seems to be a good match for them. Unfortunately they don't stack up against the HD800's in respect to sound quality. But at least I know that my AU-505 is fine. 
 
Wish the HD800's weren't so bloody sensitive. !!

In regards to my earlier post with Sansui 5000A HPO measurements, I went back and looked at some RMAA loopback tests I did on just my Auzentech Bravura. Those results also showed distortion and noise at 60Hz and its harmonics, though not quite to the extent of the Sansui measurements. That would indicate that the source of this distortion and noise is not necessarily coming from just the vintage receiver itself or a ground loop issue just specific to the receiver. That might also explain why when listening to headphones (which, you know, isn't a loopback test) I did not near a hum, noise, etc. It sounded quite clean across the spectrum as far as I could tell. It might just be an issue with my setup and how I did the measurements. Or it might really be there and I can't here it.
 
I would like to re-do my measurements once/if I can find a way to correct this, though perhaps there is little to nothing I can do about it. Any ideas? I'll keep enjoying the Sansui until (and after) then. 
 
Edit: I forgot to mention that I only did external loopback tests with the card, since an internal loopbacks tend to overestimate how well the card will do in a real/external situation. I should try an internal loopback test just for kicks...
 
I think I'll need to focus on getting the best external loopback results I can with my card first before measuring the receiver again...going to try better quality and shorter cables, try to isolate them a bit from the rest of the computer and other wires, etc. And, for all I know, the way I'm measuring this is a completely wrong way to do it...not really sure.

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silent one said:

 I wouldn't give up my Sansui for a 1980, let alone a 1250.

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Call it a morbid curiosity. I was always impressed with the little sx-650 and how well it performed for the price and size. It only seems logical that the sx-1250 would be a real beast. Plus I have very little money in the Sansui which makes selling or trading it a little easier.
 
I'd trade straight up. 

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matttcg said:

 
 
Call it a morbid curiosity. I was always impressed with the little sx-650 and how well it performed for the price and size. It only seems logical that the sx-1250 would be a real beast. Plus I have very little money in the Sansui which makes selling or trading it a little easier.
 
I'd trade straight up. 

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OH, I'm with you on that trade (9090db)...  just not with my model.

Right! SO you shouldn't trade YOUR Sansui for ANYTHING

And quite honestly, unless you have a hang up on the looks or the "mojo" of the SX-1980 (which I totally and freely admit that I DO), the SX-1250 sounds just as good, is far less expensive, and purportedly easier to fix and/or restore.

Just up the highway, someone is trying to move a 1250 on CL for $800. But I'm not sure what the market is for them right now.

I got a deal for a pair of Mordaunt Short Carnval 1 for cheap, but I still haven't gotten myself an amp yet. I came across tripath amps like lepai and topping, but I don't trust the quality of the lepai despite their glorious reviews. Topping amps however are using better quality components encased in a very solidly built housing.

On the other hand, I have my eyes on one Sansui AU 3900 mentioned previously some pages back.

I'm particularly interested with the headphone out to drive my Goldring DR150. Any of you guys had the chance to compare the performance of a tripath amp and a vintage solid state amp? Should I open a new thread for this?

Are there any mods, tweaks or component upgrades that can be done to the Pioneer SX series?

What makes the higher end SX models better for headphones than the lower end models like the SX-750? Obviously they make more power, but is that all? 

Better transformers, much better power supplies, separate amp boards, better shielding, more robust build quality, beefier caps, etc...I could go on and on.

Is any of this going to make an audible difference with headphones? I mean the SX-750 is already overkill for headphones. 
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moodyrn said:

Better transformers, much better power supplies, separate amp boards, better shielding, more robust build quality, beefier caps, etc...I could go on and on.

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jasonb said:

Is any of this going to make an audible difference with headphones? I mean the SX-750 is already overkill for headphones. 

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More controlled bass for most part.
If driving speakers, the difference is noticeable!
And, don't forget the brag rights!

jasonb said:

Is any of this going to make an audible difference with headphones? I mean the SX-750 is already overkill for headphones. 

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All of these factors are crucial. One of if not the most important aspect is power supply design. Clean power is absolutely critical. Even if you look at some of the better dedicated headphone amps today, the best ones(beta22, gsx, dark star) all have power supply's so massively built, they are housed in a separate chasis. Power supplies are what separates good amps from state of the art.

You don't have to go out and only get totl vintage gear for great sound. But from my experience with mid level and totl vintage gear, the totl were always in another league sonically. And it's why I now only buy higher end vintage gear.

Well, I'll enjoy what I have now because it already sounds better than what I was using before, but I'll keep my eyes open at yard sales and flea markets and such for the higher end Pioneers. At least this time I'll go in knowing what I'm looking for. 
Quote:

moodyrn said:

All of these factors are crucial. One of if not the most important aspect is power supply design. Clean power is absolutely critical. Even if you look at some of the better dedicated headphone amps today, the best ones(beta22, gsx, dark star) all have power supply's so massively built, they are housed in a separate chasis. Power supplies are what separates good amps from state of the art.

You don't have to go out and only get totl vintage gear for great sound. But from my experience with mid level and totl vintage gear, the totl were always in another league sonically. And it's why I now only buy higher end vintage gear.

Click to expand...