A/D/S L810A with Nakamichi 420 Power Amplifier?
- Thread starter malden
- Start date
johnebravo
I should be practicing
Where did you see that? A quick search found me this:
https://forum.audiogon.com/discussions/nakamichi-420-specs
Not a professional opinion of course; but the service manual at HiFi Engine says it's ok -- see page 18.
https://forum.audiogon.com/discussions/nakamichi-420-specs
Not a professional opinion of course; but the service manual at HiFi Engine says it's ok -- see page 18.
Last edited:
malden
Addicted Member
biscuithead
Me likes the eargasm retroplasm...
Sounds like a great excuse to get another pair of 810s, stack em, and run them in series.
Did you check for the relay referenced?
Did you check for the relay referenced?
johnebravo
I should be practicing
Ok, I see the link -- I guess I can only say that, if the official service manual gives specifications for its power at 4 ohms, they must certainly anticipate that it may be run with 4 ohm speakers, and they're not warning you off of doing that . . .
gdmoore28
Super Member
There you go, Malden. Hook 'em up and go to town. I'll bet those 810s are going to sound sweet with this combo. Follow up and let us know!
GeeDeeEmm
malden
Addicted Member
I won't be doing that but interesting idea.
No, I haven't checked but will do so. How will that help with 4 ohm speakers?
malden
Addicted Member
Ok, I see the link -- I guess I can only say that, if the official service manual gives specifications for its power at 4 ohms, they must certainly anticipate that it may be run with 4 ohm speakers, and they're not warning you off of doing that . . .
That makes sense. I have a total of three 420's, one recently went kaput. Not sure what happened but it was hooked-up to a pair of JBL 4311B's...
johnebravo
I should be practicing
I guess the only other thing that I could add would be to proceed with caution at first, and run them at moderate volume levels for a while, and check to see if the amp is getting really hot!
malden
Addicted Member
Will do
biscuithead
Me likes the eargasm retroplasm...
Let's just for a moment consider Nakdocs warning about not using them with 4 ohm speakers.... I interpret his warning as warranted citing the Class B/ heat dissipation issue. The relay board that he references could be a protection circuit . ( I admit that I know nothing about the 420)
So, I would see if you could contact him for more details.... and in the meantime... use a couple 4 ohm 50 watt wire wound resistors ( Ebay, China @ ~ $2 ea ) inline, series, with the speaker cable. This will mess with the impedance, but it will also provide a higher resistance to the amp, and essentially trick the amp into thinking it is hooked to ~8 ohm speakers. For a couple bucks, try it, and see how it sounds.
So, I would see if you could contact him for more details.... and in the meantime... use a couple 4 ohm 50 watt wire wound resistors ( Ebay, China @ ~ $2 ea ) inline, series, with the speaker cable. This will mess with the impedance, but it will also provide a higher resistance to the amp, and essentially trick the amp into thinking it is hooked to ~8 ohm speakers. For a couple bucks, try it, and see how it sounds.
I do not recommend series resistors. Yes, impedance is now 8 ohms nominal but the power produced would have to double to produce the same sound output, since roughly half will be lost in the series resistor. Heat generated in the amplifier will be similar, and you may reach voltage clipping.
The advice above to enjoy the music but monitor the amplifier temperature is good. Nakamichi made good stuff - it is doubtful there will be any problem.
The advice above to enjoy the music but monitor the amplifier temperature is good. Nakamichi made good stuff - it is doubtful there will be any problem.
