Kenwood KA-7010

A friend has given me his Kenwood KA-7010.
I really don't know much of kenwood stuff i had allready a A-62 wich looks cheap but this one is a whole other world.
After a simple cleaning the amp works perfect
The amp had some issues with the left channel but it's not there now and i hope it stays this way.
What are the common problems with this amp?
Pics will come tomorrow

I have found the problem that the friend had too.
When i tried to remove the cover to take pictures the amp lost 1 channel.
First it was the right channel and just yet the left channel.
Where to look and for what?
Please help me with this because i really like the amp.

KA-7010?

Is this a European model?

I think it is a European model.
I am not really familiar with Kenwood
I hope someone recognise this beast.

Is this Amp that rare that almost nobody knows it?
From whati've heard this amp was a TOTL in the early 90's.

This is a great machine, and a real sleeper.

Was available in the US through the Military PX system, but not through traditional hifi outlets.

One thing you'll notice right away is that it isn't built as well as many of the old units...lots of jumpers on the PC boards, and the aluminum faceplate is epoxied to the plastic guides that house the square front panel buttons and the headphone jack

There are a couple of trouble spots in this amplifier

1. the Speaker relay in the back of the amplifier (near the speaker outputs...go figure) can oxidize and cause intermittent operation
2. the front panel buttons and switches aren't sealed, and are a natural for oxidation

to get at the front panel controls you'll need to turn the amplifier off and unplug it from the wall. Then

1. remove the screws securing the front panel from the top and bottom of the faceplate (either 5 or 6 all together). Set these aside, as they're all beveled, and the screws that secure the cover aren't so you don't want to mix them up.

2.remove all the round knobs, and unscrew the large nuts securing the volume, Source and REC Out posts to the chassis (and any other nuts I may have neglected to mention

3. The front panel is now free and you'll have good access to the controls. Work deoxit into the volume, balance, Source Direct, Muting, and Bass Intensifier switches especially. I'd also give the bass and treble pots a good cleaning while you're in there

This was all it took to get two good strong channels going for me...if you continue to have issues, look at replacing the speaker relay

good luck and enjoy!

Redcoates7 thanks for the info of how to clean the pots and i think they need a good cleaning because the amp was from a heavy smoker before.
The problem i have with the amp is that when i removed the covers the amp was cutting the left output and when i moved it a bit the channel was back.

I think the cleaning will improve the amp but does'nt resolve this problem (but i can be wrong)

You might want to give it a good look for any cold solder joints as well...a common culprit on amplifiers of this vintage!

I just gave the amp the deoxit cure that does'nt hurt anyway.
I have looked for cold solderpoints but don't really know what they look like.
Can you describe how they look like?

I found a loose cable and the ADPT/Tape 3 needed more deoxit and now i can hit it with an axe if i want to but the left side does'nt cut the sound anymore
The only thing is that i don't know where to put this beast.
At first it was going to replace the AM-2600 at the pc but now i have the 2800 working there :scratch2:

Good find! Tape Monitor switches are a common culprit, as when they're not working right, the signal gets interrupted. (as you discovered)

Strong work! Hope you enjoy it

I will enjoy it
I've decided that this one will go to the laundry room to get some nice playtime.
This fix was too easy and took me about 4 hours today to discover :lmao:
I am glad i found it with your help redcoates7 :thmbsp:

Hi!

Reviving quite an old thread...

Just bought this unit. It's amazingly powerful and I really like it after my Denon AVR-1708 but there are some problems with it.
1. The sound on right channel is lower. But only at low frequency as much as I hear. High and mids are the same.
2. The input knob is not working well. I have to swith over a few possitions to get my input.
3. When I press mute, the sound cracks a bit.

What I have done:
1. Cleaned every board, potenciometers, etc... It helped with not working balance knob.
2. Changed all dried capacitors.
3. Oiled potenciometers.

What could be the causes and solutions? Especially about low bass on right channel and faulty input selector?

Thanks a lot!

Kenwood KA 7010

Ive just taken delivery of a fully refurbished Sansui AU-717 to replace my Kenwood KA 7010 Amp. I've been going back and forth between the Sansui and Kenwood listening to various classical tracks and really am having trouble finding a difference between the two. While I realize that how amps sound is rather subjective and don't have the sophisticated terms to describe the sound, the similarity I find between them should be a guide. Basically I'm suggesting the Kenwood KA7010 is a powerful and great sounding amplifier, even if it's construction seems less than optimum. The KA7010 doesn't seem to generate as much heat as the Sansui either. Playing through Celestion Ditton 66 speakers.

Warumpi, could You write something about the amplifier's output power in your tests?
f.

I picked up one of these monsters to drive some Technics 501's in my workshop, it's my fourth Kenwood so far, I new it would be powerful looking at the images on google, with the whole 100w dual mono thing going on. I had had my eye on a Mitsubishi DA-A15, but it was a fair bit more...and in a different country, I am not disappointed though :thmbsp:, this thing puts out a whole load of power and sounds great, if a bit too revealing in the high frequencies for my speakers.
I had to give it a clean and deoxit all the pots and switches as the balance was cutting out the left channel, all good now. I've been putting it though it's paces over the last two weeks, sort of breaking it back in slowly with about 6 hours play per day at about 30% and yesterday probably gave it the workout of it's life. My 501's go down pretty low and using the 'Bass intensifier' I had it wound up pretty good for about five hours playing a range of different music but mostly motown and electronic. Mated to these 501's with their titanium tweeters it can sound pretty analytical and verging on sibilant with some vocal recordings so I'm looking at a recap of the 501's crossovers, they are 42 years old anyway, and might look at the amp as well. GreddyMR2 did you notice any acoustic changes after the recap, and what brands did you change them to?
After turning off the sources when I was getting ready to leave I could hear a distinct low level hum and a high pitched whine coming from the amp :scratch2: not sure what was causing that, except the abuse I had just given it! any body else heard that? It wasn't coming through the speakers.

The hum probably comes from the transformers. Is it present all the time? Don't know about the high pitch, it usually happens with switching power supplies.

Maybe I've just woken it up a bit, but the hum wasn't present before, I'll go and look in on it now for an hour and report back

Could you describe this high pitched whine more precisely? Are a hum and whine dependent on volume knob position? Are the sources connected to the amplifier?
f.

Thanks for commenting guys, the hum is indeed coming from the transformers, I had the tuner sat directly on top of it and it had got pretty hot and it wasn't getting any air flow, that's sorted now. The whine was being produced physically by a component, the volume control position made no difference. It was still connected up to the sources: DAC, CD & tuner.
When I returned to it yesterday, it wasn't happening, so I figure it must have been due to heat build up, i'll keep an eye on it and if it recurs the cover will have to come off while its happening to see whats cooking!.. I hope it's 'burn in' period isn't literal..
It got a good clean out when I got it a couple of weeks ago, but it did have that old electronics smell for a while, its gone now but I think bringing it back into use will take a while longer, it belonged to the sellers dad and had been up in the roof for years, possibly decades and judging by the other kit that was around I don't think it had ever really been opened up in anger.