The Fisher 700-T Receiver
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Yes, and just think, John...in less than ten years the "wattage wars" were on...
And thank you 
I do not know when my 4400 was built; it's an oddball with no info out there on the Net. If I had to guess, based on the design of its brand badge I would say 1968 or 69. It uses germanium outputs which is really odd. ??? (Edit: Someone on AudioKarma said the 4400 was made in 1966 in a thread from 2010.)
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Ron Ramirez
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We discussed that before, one only needs a few watts to listen but to produce undistorted peaks the wattage potential should be large. The today's music has way more of those than the music of 30s-40s, or classical one. Back then an amp of a few watts would produce loud enough unclipped sound, whereas today you listen at the same few watts loudness (if that much) and a short peak with steep attack goes to momentary power of tens of watts. If it gets clipped your sound degrades.
One might think an amp could be designed that can have rated power of a few watts while the peak power could be made very high, and this is true, that can be done. But to me the potential problem is that if a fairly mindless person learns an amp can produce large power he might be tempted to use it constantly at that level, and this will kill the amp.
Hence the power wars.
A normal individual will listen comfrtably to a normal loudness level, but should a brainless youngster decide to put the speakers outside and deafen everyone for an hour, or damage a house's structural integrity, the amp will survive.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Mike,
On the other hand, todays music has no dynamic range. Especially when listened to on the radio. Radio stations set their processors so that there is quite literally only about 6dB difference between "pianissimo" and "crescendo" so they don't lose the volume wars.
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Brenda,
You mean "radio broadcasted music".
The same device is also an amp for a turntable or tape recorder.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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The processor units I am referring to are stand alone units between the broadcast console and the STL. Nearly all stations set them up for a very narrow dynamic range so that there is 6dB or less difference in modulation levels at any time. They call it "punching up the signal", I call it distortion.
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Agreed. But then it is radio.....
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Epilog on the 700-T:
I wasn't satisfied with the channel imbalance, which was more pronounced at low volume levels. Plus, the metallic "thump" upon power up had returned.
So today, after I spent a majority of the day studying for my A+ exams, I put the 700 back on the bench and removed the volume control. I re-installed the control I had initially put into this set, which came from a 175-T junker.
One side of the DPST off-on switch was dead, and refused to clean up. So I wired the AC sockets in back direct instead of running through the switch. One half of the switch is still good, and now turns the receiver off and on. I won't be using the rear panel AC outlets anyway, but they receive power all of the time when the unit is plugged in now.
I used my CL-80 inrush current limiter, knowing it probably isn't the correct unit for the job but since I had it on hand, I therefore used it anyway. I connected it between one side of the AC line and one terminal of the main fuseholder, as that was a convenient point to install it.
Oh, and I also removed the flexible lead LED from behind the tuning meter, and replaced it with a #47 incandescent lamp. The LED was annoyingly bright when the lights in the room were off for TV viewing.
Result: The channels are now balanced as they should be, regardless of volume setting. Bonus: No more metallic "thump" when the unit is turned on.
I would say it is now complete. It took long enough, and it was enough trouble to get to this point!
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Ron Ramirez
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Ron
So, from all this .. pethora of things fixed, what was responsible for imbalance? Volume control?
Can't be the inrush..
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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The volume control was responsible for the imbalance. With the 175-T control in the set, the balance stays correct regardless of volume setting, and it plays very well indeed now - as well as my 600-T and my 4400.
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Ron Ramirez
Ferdinand IN
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Considering it was symmetrical....maybe the values used were for different powering voltage.
Well, es ist gut.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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wow, I've been sitting on a 700-T sitting here taking up space in a similar vintage TV cabinet and never gave it much thought, compared to the 500B & C's I've accumulated, lettering all purrfect even has the round yellow "120 Watts" sticker! Even has a toggle switch for the power sticking out the top lol . . . picked it up from a garage sale ~1991 and never really used it in favor of my Dynaco stuff etc. they really put sockets in!!??
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PhilcoFordTesla,
Yes, you should get that 700-T out, freshen it up, replace capacitors as needed and use that thing! It is probably one of the best (if not THE best, 500-TX and 800-T notwithstanding) transistorized receivers Fisher ever made. It's certainly the best of their early transistor models.
Four years on, my 700-T has become the daily driver in my home office. I've noticed it is losing bass lately so it will likely need to have the PECs in the tone control circuitry rebuilt. That should be fun...not. I don't know when I'll get around to that though, it is very low priority right now.
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Ron Ramirez
Ferdinand IN
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I'll think about that, it will be right behind the Marantz Model 15 (Model 14 x 2) with two blown outputs I didn't expect during a recap and the Philco 46-1213 I need a transformer for (PN 32-8282 w' 4 secondaries) and the Model 16B with the open voice coil . . . so what do you listen to 'usually?'
I stream & rebroadcast www.kpig.com locally to all my listening apparatus whenever possible. I run 8 15" speakers upstairs with a Dynaco PAT-4 pre-amp. a pair of Altec A7-500 'VOT' clones with some short run studio type 15"ers I picked up from Tascam development guys at one end of the 1300 sqft loft/radio & tv hoard and a pair of JBL 4320 studio monitors at the other end backed up with a pair of BSR "Thunder Lizards" from the old DAK catalog IIRC driven by Dynaco 200W in front and a citation 12 HK standing in for the Marantz 15 for now at the back on the JBL's, yeah it rocks the house pretty good at a 1/2 turn on 'the knob' -or less! https://audiokarma.org/forums/index.php?...550.88661/
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