Saw this on Fox News

[N8ETQ]

Nice!

http://www.foxnews.com/scitech/2011/10/11/gold-receiver-for-your-solid-gold-records/?test=faces

[W3RSW]

Looks very similar to my Harman Kardan Citation II except the Citation uses three 12BY7's feeding the KT88's in each channel.  -multiple feedback loops, etc.  Built the Citation for my father from a kit in '64 and I think it cost a few hundred dollars at the time. Last set of KT88's installed were Mullard Gold Lions.  They were about $24 each even then.

[flintstone mop]

ONLY $6500...........but McIntosh....always loved those amps....
I owned a couple of the 40 watt amp MC30 (?) smooth sound and great response.


OLD story: Just telling a story about the unusual application of a McIntosh amplifier and the real wide bandwidth of the response. It was real!!! 10hz to 100khz plus/minus 1 dB. at rated RMS power.
To prove how good the response was for a Mac. I was an FM pirate in Washington DC, early 70's. KRAP...108.5....aircraft band
OK We went "STEREO" by injecting a stereo generator used for testing and aligning an FM stereo receiver to the input to the MAC.
This baseband, which was the stereo audio, the pilot, the other jibber jabber that makes up a composite stereo signal was input to the Mac amp. This composite output from the MAC amp went into a grid dip meter that coupled the 6mhz stereo RF into the first stage multiplier. Each additional multiplier would get us closer to the carrier frequency and the deviation would increase also. Got busted, no fine, just scared the hell out of me. But the FCC commented on the exceptional quality. No limiters, no compressors.There was a pilot carrier that lit up people's stereo light and even decent audio with about 20dB of separation. The transmitter was an aircraft transmitter using 5763's with about 600 volts on the plates. 10 watts of carrier.
End of story........sorry if it hi-jacked the thread.

Fred

[k4kyv]

Just telling a story about the unusual application of a McIntosh amplifier and the real wide bandwidth of the response. It was real!!! 10hz to 100khz plus/minus 1 dB. at rated RMS power.  

Maybe I'm being picky, but to be technically correct, that should be "mean" or "average" power, not RMS power.  There is no such thing as RMS power.  There is RMS voltage and  RMS current, but the product of the two gives average, or mean power.

But RMS voltage and current are not the same thing as average voltage and current.  Multiply the two averages together, and the product is meaningless.  Average voltage X average current ≠ average power.

This can be confusing, and I have seen numerous otherwise excellent professionally-written papers, particularly on subjects involving audio/hi-fi/stereo, erroneously refer to something called "RMS power".

[W3RSW]

I always just assumed that "RMS power" just meant a continuous sine wave at so many volts input amplified to produce a constant output vs. the "music power" crapola of so many amps at the time that was, say, 20% duty compared to a constant sine wave. 

-Never gave it much thought other than trumping the wattage wars raging a the time.

[Opcom]

Avast ye hijacking Pirate!  I enjoyed the story..

ONLY $6500...........but McIntosh....always loved those amps....
I owned a couple of the 40 watt amp MC30 (?) smooth sound and great response.


OLD story: Just telling a story about the unusual application of a McIntosh amplifier and the real wide bandwidth of the response. It was real!!! 10hz to 100khz plus/minus 1 dB. at rated RMS power.
To prove how good the response was for a Mac. I was an FM pirate in Washington DC, early 70's. KRAP...108.5....aircraft band
OK We went "STEREO" by injecting a stereo generator used for testing and aligning an FM stereo receiver to the input to the MAC.
This baseband, which was the stereo audio, the pilot, the other jibber jabber that makes up a composite stereo signal was input to the Mac amp. This composite output from the MAC amp went into a grid dip meter that coupled the 6mhz stereo RF into the first stage multiplier. Each additional multiplier would get us closer to the carrier frequency and the deviation would increase also. Got busted, no fine, just scared the hell out of me. But the FCC commented on the exceptional quality. No limiters, no compressors.There was a pilot carrier that lit up people's stereo light and even decent audio with about 20dB of separation. The transmitter was an aircraft transmitter using 5763's with about 600 volts on the plates. 10 watts of carrier.
End of story........sorry if it hi-jacked the thread.

Fred

[W1RKW]

I picked up 2 MC30's 20 years ago out of the trash.  Retubed them, did a little clean up and sold them for a grand.

[N8ETQ]

Hey Fred,

     Great story,  I was at the other end of the band  88.7 (top of tv ch. 7) with an RT-68
running into a HB single 4CX150 doubler up to 88 mc. Didn't have any stereo gen. but
did use an HP audio gen to pump in 19 kc to turn on the stereo LED.  Had a big Arse
4 element yagi suspended from the rafters of my attick. Audio was furnished via my
Dokorder (I still have) 10.5" reel to reel deck. At 3 1/4 IPS we could get about 6 hours
of play time.  We didn't have a MIC, but always (amongst ourselves) refered to it as
WEED and would ride around NE ohio in my '72 Coupe De Ville (with skirts) and
a Kraco in dash AM/FM/CB/Cassette.  I miss the analog tuners to this day.

     Inspiration fer Sat Radio?

   You did'nt hijack the thread, Perhaps  just Re-defined it. Good job OM.

73

/Dan


OLD story: Just telling a story about the unusual application of a McIntosh amplifier and the real wide bandwidth of the response. It was real!!! 10hz to 100khz plus/minus 1 dB. at rated RMS power.
To prove how good the response was for a Mac. I was an FM pirate in Washington DC, early 70's. KRAP...108.5....aircraft band
OK We went "STEREO" by injecting a stereo generator used for testing and aligning an FM stereo receiver to the input to the MAC.
This baseband, which was the stereo audio, the pilot, the other jibber jabber that makes up a composite stereo signal was input to the Mac amp. This composite output from the MAC amp went into a grid dip meter that coupled the 6mhz stereo RF into the first stage multiplier. Each additional multiplier would get us closer to the carrier frequency and the deviation would increase also. Got busted, no fine, just scared the hell out of me. But the FCC commented on the exceptional quality. No limiters, no compressors.There was a pilot carrier that lit up people's stereo light and even decent audio with about 20dB of separation. The transmitter was an aircraft transmitter using 5763's with about 600 volts on the plates. 10 watts of carrier.
End of story........sorry if it hi-jacked the thread.

Fred
[/quote]

[ke7trp]

I thought about buying one of those and sealing it in plastic and stashing it in the closet.  If I am around in 30 years, It could be worth triple.

My uncle and grandpa built the citations when they came out as a father and son project in the basement.  When my uncle told me this I asked where they where and was told "probably in the basement".  Long story short, My grandpa set them out at the curb for donation. DOH!!!

I had the pleasure of meeting Sidney Harman.  I am friends with one of his Kids.  I stayed in his Guest home years ago on the west coast. Sidney gave me a tour of his main audio setup in the living room of the main house.  Hand built by the infinity engineers into the walls Sounded fantastic.  Also he had a small modest home theater where he tested different products of his. I mentioned to him about my grandpa throwing out the citations.  He laughed and said something shocking to me.  He said tubes where dead long ago and there would be no point to use anything tube anymore.  Solid state gear was many many many times greater in performance and sound  

The following day, we drove over to the headquarters and I got tour of the manufacturing plant for some of the major brands the company owns.  Infinity, JBL,  Mark Levinson, and hk.

The highlet for me was going to the Speaker/amp test vault where there where racks and racks of Amplifiers running at full volume and then over 100 speakers at full volume.   This was a sealed double door sound proof vault. We had to wear ear protection and warned NOT to remove them.

We lost Sidney this year. He was a very nice man and had a great impact on audio.

C

[WBear2GCR]

Rick, the Citation II has no real circuit resemblance to the McIntosh design. They both use transformer cans that look similar, then after that everything is different.

The Citation is more or less a "standard" amp design. The McIntosh uses what they call "Unity Coupling" in the output transformer. That means they split the primary in half, cutting the impedance by 1/4 and putting half in the plate and half in the cathode. Now the output tube behaves like a follower, no gain. All the gain has to come from the driver stage.

This last bit was a problem in the early and very high power version that used 8005 output tubes. They had to bootstrap the drivers in order to get enough drive swing!

The advantage of the McIntosh output transformer design is exactly the dramatically better performance achieved due to the "trick" I mentioned before. This also permits them to bifilar wind it... giving further benefits in freq response...

                     _-_-bear

[VE3GZB]

Nice but what's with the green light beneath the small tubes? That makes it seem cheesy.