Nakamichi DR-3 Tonal Imbalance Troubleshooting

[Amithu]

Hey everyone,

I recently acquired a Nakamichi DR-3 two-head cassette deck and encountered a peculiar issue with tonal imbalances between the channels. Here's a summary of my troubleshooting steps and observations:

1. Tested with a CD player on the preamp, yielding normal sound, confirming the preamp, amplifiers, and speakers are functioning correctly.

2. Changed interconnect cables with known good ones, ruling out cable issues.

3. Swapped interconnects from the deck to the amp, observed the tonal imbalance switching sides on the speakers, indicating the issue is within the cassette deck.

4. Ran multiple pre-recorded cassette releases and known good cassettes, consistently experiencing the same tonal imbalance.

5. Demagnetized the head to eliminate magnetic buildup as the cause.

6. Confirmed that the playback speed is normal, eliminating speed-related issues.

7. Attempted adjusting the azimuth angle on the playback head, but no noticeable change occurred across the adjustment band.

Despite these efforts, the tonal imbalance persists across different tapes, suggesting an internal issue within the cassette deck. Further troubleshooting involves checking head alignment, inspecting internal circuitry, cleaning controls and switches, and seeking insights from Nakamichi enthusiast communities. If the problem persists, considering professional assistance may be the next step.

Any advice or insights from the community would be greatly appreciated!

 

[dankik]

Do you also have the same "tonal imbalance" if you:

• Put the deck in REC-Pause,
• Play your source CD, and
• Monitor the source on the Tape Outputs as well as the headphone output?

 

[WernerO]

1.as above

2.you don't say what tonal imbalance, in which channel

3.unless you have no treble response at all changing azimuth will be readily audible

4.when you run a fingernail across the head's top surface, do you feel a groove or ridge?

 

[Amithu]

Do you also have the same "tonal imbalance" if you:

• Put the deck in REC-Pause,
• Play your source CD, and
• Monitor the source on the Tape Outputs as well as the headphone output?

I did exactly as you said.
Here is the observation.
1. In Rec+Pause the audio seems well balanced across the channels. And VU meter shows equal jumps according to the signal.
2. In Rec+play same as above.
3. When I played the same recorded content in same deck, both channels not only show tonal imbalance but also the left channel has lower output. The vu meter of left channel is also jumping lower than vu meter of right channel consistently .


Additionally twisted recording balance towards left (10 O’clock) to see if it can compensate for the recording offset. I started recording, while recording left channel was almost really loud against right, the vu meter confirmed the same. After completing recording, when I played back the cassette, again the right channel was much louder than left channel and vu meter confirmed the same.

 

[Amithu]

1.as above

2.you don't say what tonal imbalance, in which channel

3.unless you have no treble response at all changing azimuth will be readily audible

4.when you run a fingernail across the head's top surface, do you feel a groove or ridge?

Response for 2- on preeecorded cassettes and known good cassettes, left channel only throws out mods and bass, right channel only pumps out mods and trebles.

3. Did tweet the azimuth screw several rotation both clock and anti clockwise but the tonal imbalance as described above did not get affected much.

4. Absolutely I can feel the groove on both bands within the blue rectangle of the head.

 

[Amithu]

Thankyou Very much for the support. With your pointers, I've switched the cables running on head and identified that the issue lies with the head, and I'm seeking your guidance on finding a suitable replacement or upgrade for enhanced performance. Could you recommend a specific model and make, and let me know if it's available on Alibaba or AliExpress?

 

[WernerO]

left channel only throws out mods and bass, right channel only pumps out mods and trebles.

a worn head does not cause lack of bass. seek someone competent, suitably-equiped, who can check the deck for you.

Could you recommend a specific model and make

you won't find a direct replacement for the Canon sendust head. if damaged it can be relapped, if you find someone. if shot it has to be replaced by one of a parts deck, or by a different type. in that case the deck's rec and play amps have to be adapted to the new head. you need experience and costly tools for that.