[fjosh]

   
Nice Yammy.  Question - are you using it with your TV system?  And if so, how is it configured?  I've been toying with doing this with one of my spare vintage amps. 

 
It coincides with the Yamaha RX-V667 above it which has preouts.  The CA-1010 is powering the main L/R Polk RTA-12B's and the RX-V667 is powering the Polk Monitor 5 centers and Polk Monitor 4 rear surrounds (not pictured).
 
I can use either receiver for my headphones.

 

[kstuart]

 

There is currently no complete scientific theory covering all of acoustic and/or audio reproduction.  Trial-and-error shows that certain measurements have certain correlations in some circumstances - and that makes it easier to design headphones, rather than having no starting point at all.

It's possible someone in the DIY Forum here, has tried changing the output impedance of the amp he designed and built...

Ohms law.

Ohms law is electrical, and is not about acoustics or audio, and lastly is not a complete scientific theory.   It's very helpful in designing any electrical circuit, but doesn't tell you what it will sound like.

 

[palmfish]

I was responding specifically to jasonb's comment about wishing he knew the science behind why the HD800 will sound bassier powered by a high output impedane vintage amp.

Amplifiers and headphones are electrical devices, and Ohms law explains why a high output impedance acts as a voltage divider, thus causing the frequency response to mirror the impedance curve.

 

[5aces]

.Do you know how many 20000 did Sausui produce? It seems the most expensive IA in vintage models.

I have no definitive answer for the units sold but Sansui was at their peak for sales in 1976, some say.
Still remember walking into a Sansui dealer that sold a ton of stereo gear to University of Toronto students.
Picked up a brand spanking new set in '76, was I ever pumped that day...
An old AU 20000 is worth the repairs to keep it running.
Like the old car show says "Don't Crush Them, Restore Them"

Put a bid cap in for $940, you just never know, it's still sitting below $700 atm.

 

[roadcykler]

  Ohms law is electrical, and is not about acoustics or audio, and lastly is not a complete scientific theory.   It's very helpful in designing any electrical circuit, but doesn't tell you what it will sound like.

 
And it's almost 100% guaranteed that your ears are the only thing that will accurately tell you what something sounds like. Anyone can tell you what something sounds like, but until you hear it for yourself, it's a guess.
 
A recent example. Stereophile and lots of other outlets have given high praise to these small Pioneer speakers that were designed by Andrew Jones (some supposedly great speaker guy). I happened to see that they were on sale at Best Buy and thought I would buy them for my small computer room. When I first played some music, the highs were hardly there. Even when I asked my wife (who couldn't care less about audio) to listen to them, with no prompting she said that the "high part" seemed to be muffled or lower. 
 
I took them back the next day and stuck with the Paradigms I already have. Let your own ears be your judge.   

 

[Trav]

And it's almost 100% guaranteed that your ears are the only thing that will accurately tell you what something sounds like. Anyone can tell you what something sounds like, but until you hear it for yourself, it's a guess.

A recent example. Stereophile and lots of other outlets have given high praise to these small Pioneer speakers that were designed by Andrew Jones (some supposedly great speaker guy). I happened to see that they were on sale at Best Buy and thought I would buy them for my small computer room. When I first played some music, the highs were hardly there. Even when I asked my wife (who couldn't care less about audio) to listen to them, with no prompting she said that the "high part" seemed to be muffled or lower. 

I took them back the next day and stuck with the Paradigms I already have. Let your own ears be your judge.   

I also listened to them briefly but the environment wasn't optimum and passed on them as well. Jones is one of the TAD Reference guys. Quite a resume.

 

[calipilot227]

I own a pair myself (SP-BS21LR), and I thought they were on the bright side. I used them in a nearfield setup for quite some time.

 

[SpeakerBox]

   
And it's almost 100% guaranteed that your ears are the only thing that will accurately tell you what something sounds like. Anyone can tell you what something sounds like, but until you hear it for yourself, it's a guess.
 
A recent example. Stereophile and lots of other outlets have given high praise to these small Pioneer speakers that were designed by Andrew Jones (some supposedly great speaker guy). I happened to see that they were on sale at Best Buy and thought I would buy them for my small computer room. When I first played some music, the highs were hardly there. Even when I asked my wife (who couldn't care less about audio) to listen to them, with no prompting she said that the "high part" seemed to be muffled or lower. 
 
I took them back the next day and stuck with the Paradigms I already have. Let your own ears be your judge.   

 
Agree 100%.  I am an electrical engineer and have been designing speakers for over 30 years as a hobby.  The math is almost never the last word.  I always end up tweaking (and tweaking, and tweaking,.........) the final sound by ear, and as I understand it Henry Kloss did some of that with the Advent design too.  It is not an exact science.

 

[Newschool]

I recently got a Mcintosh mc2205 speaker power amp from my dad that's from the late 70's. 200 watts per channel rms and 500 watts per channel peak. And that's rated true across the entire frequency range with low distortion to 500 watts. Really an amazing amp. It has an auto former so it has 1 ohm, 2 ohm, 4 ohm and 8 ohm taps. I've been using it to power my cerwin vega speakers and it should be powering some magnepans within the next month. I've also been using the 1 ohm tap to power my dt990's and my cousin's he500's (he is nimzerz on headfi). Sounds amazing and has unlimited power. Works out to be 1 watt into 250 ohms and about 10 watts into 28 ohms. Perfect for both of our headphones.

I'm out of town but ill post a picture when I get home this weekend.

 

[LugBug1]

I recently got a Mcintosh mc2205 speaker power amp from my dad that's from the late 70's. 200 watts per channel rms and 500 watts per channel peak. And that's rated true across the entire frequency range with low distortion to 500 watts. Really an amazing amp. It has an auto former so it has 1 ohm, 2 ohm, 4 ohm and 8 ohm taps. I've been using it to power my cerwin vega speakers and it should be powering some magnepans within the next month. I've also been using the 1 ohm tap to power my dt990's and my cousin's he500's (he is nimzerz on headfi). Sounds amazing and has unlimited power. Works out to be 1 watt into 250 ohms and about 10 watts into 28 ohms. Perfect for both of our headphones.

I'm out of town but ill post a picture when I get home this weekend.

 Good stuff

 

[Sekka]

Would something like the Harmon Kardon 630 be audibly better than say, the FiiO E9K for a headphone like the Mad Dog?  Would it work well with a low impedance, low sensitivity headphone, or would it blow the drivers and my eardrums?
 
I don't know much about vintage receivers, but they seem to put out an insane amount of power for almost nothing and have ridiculous build quality.

 

[pixelsphotopro]

  Would something like the Harmon Kardon 630 be audibly better than say, the FiiO E9K for a headphone like the Mad Dog?  Would it work well with a low impedance, low sensitivity headphone, or would it blow the drivers and my eardrums?
 
I don't know much about vintage receivers, but they seem to put out an insane amount of power for almost nothing and have ridiculous build quality.

 
What do you described as ridiculous build quality?

 

[Sekka]

   
What do you described as ridiculous build quality?

Ridiculously good, at least compared to something modern of the same price.
 
Wasn't the point of my post, though.

 

[pixelsphotopro]

  Ridiculously good, at least compared to something modern of the same price.
 
Wasn't the point of my post, though.

 
Sorry I did not read the previous post.

 

[moodyrn]

Ok one last update on the marantz 2325 saga. I last reported that ebay ruled in my favor and gave me  full refund and told me the item was mine to do what I wanted to do with. At the time I was really upset with the seller by how he treated me and thought about just keeping it since I didn't have to return it. After cooling off for a few days, I decided to give him one last chance. I told him if he would just send me a shipping label or send me funds to cover shipping, I would still be willing to ship it back to him.
 
To my utter surprise, he said no. Instead he wanted me to pay him again. So I guess the guy never really wanted it back, and knew what he was sending me wasn't anything close to what was in his description. All I ever asked for from the beginning was to ship it back on his dime. Unbelievable!!