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  #1  
Old 08-05-2011, 03:34 AM
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allthingsanalogue allthingsanalogue is offline
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Denon DRM-700, any good

Is the Denon DRM-700 a decent deck?
  #2  
Old 08-05-2011, 04:26 AM
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A.N.T. A.N.T. is offline
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Quote:
Originally Posted by allthingsanalogue View Post
Is the Denon DRM-700 a decent deck?
Not without some modifications, same goes for DRM-800 - these two share almost exactly the same circuit but different mechanisms and heads, single capstan and permalloy heads for DRM-700, dual capstan and amorphous heads for DRM-800.

Main problems are - a very strong interference from the fluorescent display and flat cable that connects it to the main board (needs some proper screening, I've used copper foil to do it), clipping on the REC MUTE transistors on the input of the recording amplifier (as a result the deck distorts at near 0 dB when records, even if the tape allows for much higher levels) and JFET output mute switches that add a lot of distortion on the output.

On top of these big problems there are also 4066 CMOS switches for the monitor switch in both decks and (very nasty) a 4066 switch in the DRM-800 for two inputs (in the DRM-700 it is absent as it has only one input and no switching).

After fixing these problems it could be a decent deck.

Alex

Last edited by A.N.T.; 08-05-2011 at 04:29 AM.
  #3  
Old 08-05-2011, 04:28 AM
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allthingsanalogue allthingsanalogue is offline
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thanks, i'll give it a miss!
  #4  
Old 08-05-2011, 05:25 AM
CottonSwab CottonSwab is offline
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Quote:
Originally Posted by A.N.T. View Post
Not without some modifications, same goes for DRM-800 - these two share almost exactly the same circuit but different mechanisms and heads, single capstan and permalloy heads for DRM-700, dual capstan and amorphous heads for DRM-800.

Main problems are - a very strong interference from the fluorescent display and flat cable that connects it to the main board (needs some proper screening, I've used copper foil to do it), clipping on the REC MUTE transistors on the input of the recording amplifier (as a result the deck distorts at near 0 dB when records, even if the tape allows for much higher levels) and JFET output mute switches that add a lot of distortion on the output.

On top of these big problems there are also 4066 CMOS switches for the monitor switch in both decks and (very nasty) a 4066 switch in the DRM-800 for two inputs (in the DRM-700 it is absent as it has only one input and no switching).

After fixing these problems it could be a decent deck.

Alex
Alex,

That's a nice tip on the display harness I am going to check out my DR-M24 and 44 HX units and see whats up there. -Thank You

Those 4066 CMOS gates are extremely prone to static failure. Always were.

Ron
  #5  
Old 08-05-2011, 05:27 AM
CottonSwab CottonSwab is offline
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Quote:
Originally Posted by allthingsanalogue View Post
Is the Denon DRM-700 a decent deck?
I don't think the "Calibration" record level can be set for either of these. I have looked at them too. Otherwise they seem nice save for what Alex recommends...
Ron

Last edited by CottonSwab; 08-05-2011 at 08:58 AM. Reason: To clarify Calibration Record Level
  #6  
Old 08-05-2011, 07:11 AM
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of course, i guess you meant the "calibration record level"... that is missing on many decks... because saying simply "record level" we may do a bit of confusion with the "input record level" that is present on any standalone decks.

CHEERS,

Vince.
  #7  
Old 02-08-2016, 02:10 PM
ChopperCharles ChopperCharles is offline
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Don't forget that the capstan is mounted with plastic parts, not metal. They're under a lot of tension via the pinch roller, and they break... leaving you with massive tape skew and a pretty much useless deck. I yanked the heads and binned the rest.


Charles.
  #8  
Old 02-08-2016, 04:11 PM
Wojszwillo Wojszwillo is offline
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For Denon's go for Denon DR-M33HX (manual bias tune) or Denon DR-M44HX (auto calibration of level and equalization).
Transports for these are almost the same for both (44 - direct drive, 33 belt driven; other - the same) and electronics are almost the same, except auto calibration board of DR-M44HX.
Both have the same perfect Alps heads.
Very nice sound.
When transport calibrated / greased etc. properly, you can have such W&F as of my 44.
Attached Images
File Type: jpg Denon DR-M 44 HX.jpg (48.4 KB, 8 views)
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Jamo E850 PDD, Jamo E8SUR.2; Technics SL-Q2, audio-technica AT150MLX, audio-technica MG-10; Denon DR-M44HX; Denon DVD-3930, Denon DVD-2930; Denon AVR-3806; Panasonic NV-HD687

Last edited by Wojszwillo; 02-08-2016 at 04:45 PM.
  #9  
Old 02-08-2016, 07:51 PM
ChopperCharles ChopperCharles is offline
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One question though, does the DRM-700 have the good ALPS heads?

Charles.
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