AK (hot rodded) Ampex ATR-102's w/MR-70 Preamps replaces my Studers.

Despite their overly-robust power supplies, stock MR70 channels typically draw just a bit under 60 watts in Record - a bit less in PB (since the record circuitry B+ is switched only when actively recording). Fused at .75A/channel.

An entire 2-TK MR70 machine only draws about 3.5 amps from a 117v line - and the load remains fairly constant in use.
thanks Tom, for the clarifications. my wattage draw numbers are from 'AK', so not sure whether his modifications caused a higher draw or if he was just communicating a ballpark with a fudge factor for my consumption. i'll ask him when i get a chance.
 
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I have never owned an Ampex RTR so I can’t comment on their sound but neither of my stock Studers sound as good as my Doshi tape preamp. I love the Studers’ transports (and the Technics RS-1500 tape handling as well), but the sound doesn’t compare.
It occurs to me that tape transports are analogous ;-) to turntables, repro heads correspondent to cartridges as transducers, and the circuit(s) which follow for amplification/EQ, etc. These are systems wherein a change can be manifestly observable.
 
overall agree to a degree, but when you add the factory Studer Trafoless output cards to the A-820 (all three of my A-820's had these), the sound becomes more micro-dynamic and vivid. so more like the original stock ATR

i understand. the A-820 is a complicated machine.
The trafoless cards do sound different. I have both types for my tandem of A-820's. Indeed, the A-820 is an extremely complicated device. A mod somewhere can very well have unintended consequences.
 
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one thing i've discovered with the AK 'hotrod' ATR-102's is that with both AK MR 70 preamps, and my AK ATR-102 fired up, i am reaching the limits of my 20 amp breaker for that outlet leg inside my Equi-=Tech Wall Panel System. so i likely need to install a fresh breaker.

turns out the stock power supply of the ATR-102 uses 4 times as much current as the stock A-820's. maybe a good reason why the ATR-102 seems punchier. it's throwing more current at the issue. i realize i'm connecting dots above my level of understanding. but it's likely there is some cause and effect going on.

before with 3 Studer A-820's and the King Cello all connected to that same 4 gang outlet and all powered up, i never had any issues.
Fascinating. From an Ampex ATR-100 Operation/Maintenance Manual: +/- 22 Vdc (nominal) for the audio signal system circuitry and 0.6 kVA maximum (with all accessories) power consumption, i.e. 600 W. Of course, stock devices. A-820 power consumption, 450 W.
 
speaking to AK, my post about the power consumption of the hot rod ATR's and MR-70's are off the mark. i did not properly understand what he told me. i should stay in my lane.....and that's not techie stuff.

sorry for the confusion.
 
this afternoon i was playing 1/2" tape on the AK ATR-102 and MR-70. i played a 1/2" tape of a 1st generation dub of 15ips and 30ips work parts from a Ilia Itin solo piano recording of Debussy Preludes. (AK did my dub and has all the original session tapes). the same mic feed fed a Quad dsd recording and reel to reel both 1/2" 15ips and 1/2" 30ips. the MR-70 preamps each have a switch on top to change the EQ from 15ips to 30ips. and i have the raw Quad dsd files from the same session.

the Quad dsd files are excellent, maybe as good a piano as i have heard digitally. clean, nice sense of venue, wonderful tone, dynamics, decay and feeling of the power of the piano.....zero sense of anything processed. but the 1/2" 15ips surpasses the digital in everything, and the 30ips goes a step further. it's especially interesting how the analog does the peaks comparatively.......and the ambient information, projection of power and authority. so much ease and headroom in the information handling. it allows your brain and body to relax into the music. experientially different than the digital.

and this is the tip top of the food chain for both formats.

does digital have as much information as the tape? no.

 
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Good news , i can buy a lot of tapemachines and tapes for Wadax money . :)
but you will run out of tape titles before you run out of money. the Wadax will never run out of new music.

but i respect that great tape is awesome.....it's a different creature from streaming digital.....can't really compare them at all.
I do like the Wadax presentation as well though and im sure the convenience is hard to beat
i can't make any ROI sense of it, and i don't try to. i know i just love to to sit back and just let the Wadax play anything, and everything.....for hours and hours and i never tire of it. then do it again. nothing else has ever done that, like that.

where was i? i don't recall. :rolleyes: and that's the point. being there....is worth it. for me.

YMMV
 
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my friend Andrew (AK) is here today installing the 1/4" MR-70 preamps, with the Flux Magnetic heads, doing calibration now. these MR 70 preamps are joining the ones for the 1/2" i already had.

we have decided to use both ATR-102's for the MR-70 preamps, 1/4" and 1/2" separate, so i won't need to swap headblocks and plug and unplug cables to the MR-70 preamps.

listening reports later.

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i was watching the NCAA BB Final Four this afternoon, so when the first game ended came downstairs and have done 20 minutes listening to the 1/4" MR-70. i had let it warm up the last three hours, so it's nice and warm.

chose a 70's Ben Webster live jazz club recording. words that come to mind. dynamic and immediate. pure. dense textural tone. grainless. ultimate realism. second BB game is starting now. will come back down at half time, and if it's a blowout will leave early. going to be a late night listening to tape.
 
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Had the chance to sample to 1/4" tape at Mike's yesterday. Live recording of Ben Webster was spooky good. Also listened to "Acknowledgement" from "A Love Supreme" which was the best sounding version I've ever heard.
 
tonight so far a tape night.

first was a 1/4" 15ips dub by Yes, "Fragile". 'Roundabout' was epic. but reel 2 (side 2) knocked my socks off. it flows. don't know the provenance of this tape, but it's quite a bit better than my AP 33rpm vinyl reference....which i think is very good.

right now it's TP-008 1/4" 15ips of The Tape Project; Bill Evans Trio, 'Waltz for Debbie'. i had been pretty happy with this tape over the years, a slight little bit better than my much loved AP 45 pressing. now with the MR 70 there is a more clear step up in all areas. lower noise, more ambience, ease, realism and dynamics. players in space. you are there. the shimmer of the high hat is completely 'hair raise-ingly' real. the piano very full bodied, great tone colors and sparkling with energy.
 
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three weeks ago i got my 1/2" ATR-102 w/MR 70 pre's back from some tweaking by AK (Andrey Kosobutsky). he lowered the noise floor, improved micro dynamics, and even got the reels running smoother. when he returned it, he took my 1/4" ATR/MR 70 and has had it for 3 weeks also optimizing it. tonight he returned it. i finally have both decks together, and all the MR-70 pre's on the rack and now i can just listen. the 1/4" is also better than before. these are simply final tweaking processes (not going to try to describe what he did technically).

musically it's got more ease and the clarity is better, noise is reduced, the music has a greater jump factor. get's more under your skin. at this level, these are small little changes, but appreciated.

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but you will run out of tape titles before you run out of money. the Wadax will never run out of new music.

but i respect that great tape is awesome.....it's a different creature from streaming digital.....can't really compare them at all.

i can't make any ROI sense of it, and i don't try to. i know i just love to to sit back and just let the Wadax play anything, and everything.....for hours and hours and i never tire of it. then do it again. nothing else has ever done that, like that.

where was i? i don't recall. :rolleyes: and that's the point. being there....is worth it. for me.

YMMV
But I will run out of time before I run out of tapes..........
 
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But I will run out of time before I run out of tapes..........
you are likely a unicorn being able to make your own high quality tapes of an orchestra for years. if i had that sort of tape access it might skew my ROI viewpoint on the Wadax too. but it's not a real world choice for (almost all of) the rest of us. or maybe our life expectancy is very short. hope it's not that.

i have maybe 225-250 high quality reel to reel tape albums (most are 2 reel titles), which is more than most do. where as i have 12,000 records, and infinity of digital streaming files to access. the Wadax has lots of relevancy for me. the user experience is superb. not saying it's a bargain. this is a hobby where we get crazy about stuff for sure. some even make their own orchestral tapes. :rolleyes: that's really crazy.

and my comment you responded to was in response to @andromedaaudio.
 
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But I will run out of time before I run out of tapes..........
You are a very lucky man! It was my inability to get consistently good tapes that caused me to sell my reel to reel and all my tapes. After I spent $500 for a Steely Dan Aja tape that my $50 MOFI record absolutely crushed, I was turned off.
 
You are a very lucky man! It was my inability to get consistently good tapes that caused me to sell my reel to reel and all my tapes. After I spent $500 for a Steely Dan Aja tape that my $50 MOFI record absolutely crushed, I was turned off.
not all grey market tapes are created equal.

when i was in my tape acquisition buying mode, about 10-15 years ago when i acquired most of my tapes, i would try to only buy tapes that were better than my best pressing. which i could do many times by making that a condition of purchase. was not always possible.

certainly tape playback excellence can never be assumed. but it's also not entirely out of your control. it does take time to figure out what source is most reliable. and that process is expensive. but so is chasing great pressings. i have to really be emotionally connected to music to acquire the tape. i buy records i might only play once. but not tapes.

and now with my new/old/hot rodded tape machines, some tapes i thought were not superior to my pressings, maybe a trade-off, now are clearly better than those pressings. my current playback has upped the game for what SOTA tape can be.
 
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