THD
Active Member
What kind of output transistors do they use?
THD
Active Member
Except for the dreaded Mt-200 output transistors, look like the ones used in a KA-801. The L-05 uses the wonderful T03s.
THD
Active Member
Except for the dreaded MT-200 output transistors like the ones used on the KA-801 & the like. The L05M uses the wonderful TO3s. I would have steered clear because of those but that's just me, as long as they work it's all good.
I have the L-06M's back out for a full recap. What a nightmare it was to pull them apart. No molex connectors, All wire wraps. 
I am still searching for the service manual for these. I will need it to adjust both amplifiers, also to troubleshoot the relay problem.
I have 2 new relays coming, as well as new speaker terminals, RCA jacks, and Nichicon audio grade caps.
I'll keep you all updated! If anyone reading this has access to the correct service manual and related schematics, it would be greatly appreciated if you can share them!!!
I am still searching for the service manual for these. I will need it to adjust both amplifiers, also to troubleshoot the relay problem.
I have 2 new relays coming, as well as new speaker terminals, RCA jacks, and Nichicon audio grade caps.
I'll keep you all updated! If anyone reading this has access to the correct service manual and related schematics, it would be greatly appreciated if you can share them!!!
Fully recapped one of the L-06M's and got it back together. Ran through everything and powered it up. It blew the main 5A fuse. I checked over everything once more and found that I had forgotten to hook the thermal sensing diode back up. I hooked it back up, and unplugged all of the output modules. I powered the amplifier back up and got a relay click...
With no schematic or service manuals, I'm kind of chasing my tail. I checked over my soldering, wiring, and capacitor polarity. I haven't tried hooking the outputs back up in fear I might do more damage. The outputs are 2SA1095 & 2SC2565. Any advice?
With no schematic or service manuals, I'm kind of chasing my tail. I checked over my soldering, wiring, and capacitor polarity. I haven't tried hooking the outputs back up in fear I might do more damage. The outputs are 2SA1095 & 2SC2565. Any advice?
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Okay, I figured it out.
It turns out that one of the connectors that slides on to the output transistor legs was touching the heat sink. It's a terrible design, and the slightest bump can push the legs right up against it.
Installed a new fuse, and it came to life. Starting on the next one tomorrow. I'll attach photos tomorrow as well!
It turns out that one of the connectors that slides on to the output transistor legs was touching the heat sink. It's a terrible design, and the slightest bump can push the legs right up against it.
Installed a new fuse, and it came to life. Starting on the next one tomorrow. I'll attach photos tomorrow as well!
Blue Shadow
Waiting for Vintage Gear from this century
Hey I used one of them damn things, but that was a copy image of Mark's post.
I finished the L-06M's yesterday and have been using them all day today. They are sounding spectacular! I can finally evenly compare them against my L-07M's 
Between the 2 monoblocks, I changed 24 capacitors, 2 relays, 8 binding posts, and 2 RCA jacks. I re-flowed a ton of solder joints on the main boards as well.
I'm happy to say that the constant relay clicking in the one monoblock has gone away!
I used Nichicon Fine Gold caps all around, and Omron MY4-02 DC24 relays.
Here are a few photos of the work on one of the L-06M's. The work was pretty time consuming because of the fact that Kenwood used wire wraps for all of the point to point wiring. No connectors. Other than that, the chassis came apart and went back together relatively easily.
Between the 2 monoblocks, I changed 24 capacitors, 2 relays, 8 binding posts, and 2 RCA jacks. I re-flowed a ton of solder joints on the main boards as well.
I'm happy to say that the constant relay clicking in the one monoblock has gone away!
I used Nichicon Fine Gold caps all around, and Omron MY4-02 DC24 relays.
Here are a few photos of the work on one of the L-06M's. The work was pretty time consuming because of the fact that Kenwood used wire wraps for all of the point to point wiring. No connectors. Other than that, the chassis came apart and went back together relatively easily.
j!m
Super Member
As I recall, the sigma drive was used to get the feedback signal for the amplifier direct from the voice coils of the speakers. The idea was to have exceptional damping factor.
But, any mono block run really close to the speakers (really short speaker cables) does essentially the same thing.
When I went to long interconnect (balanced) and short speaker cables, it made a huge difference in how my system performed overall. Not Kenwood amps (Counterpoint) but same idea.
Pretty innovative for the time.
But, any mono block run really close to the speakers (really short speaker cables) does essentially the same thing.
When I went to long interconnect (balanced) and short speaker cables, it made a huge difference in how my system performed overall. Not Kenwood amps (Counterpoint) but same idea.
Pretty innovative for the time.
HackWhite, I noticed you changed the sigma drive binding posts from stock. Red and Black sigma posts are flipped.
Why?
Why?
Good catch! I took that photo while test fitting the jacks. They've since been swapped around. All is well
If anyone is looking for a pair of L-06M's, there seems to be a pair on Buyee (Yahoo Japan) for a buyout price of roughly $450
Seller says that they have been refurbished, so might be worth a shot!
https://buyee.jp/item/yahoo/auction/k444176668?conversionType=search_suggest
(not affiliated)
Seller says that they have been refurbished, so might be worth a shot!
https://buyee.jp/item/yahoo/auction/k444176668?conversionType=search_suggest
(not affiliated)
Blue Shadow
Waiting for Vintage Gear from this century
These L-0 amps sure are a different build than most amps. Parts come out all kinds of different ways. Refurbing that pair of L-07Ms I did was so nice to be able to unplug and remove the transformer to make the remaining unit much easier to mess with.
Blue Shadow
Waiting for Vintage Gear from this century
Nice.
What other amps have you used that these outperform?
What other amps have you used that these outperform?
I've had lots of amplifiers come through my hands since moving to NJ. Lots more people down here are happy to lend gear which is awesome.
I had a Classe CA-150 and a Threshold S300 in from a friend the other day and the L-06Ms easily beat them. Off memory, they also sound better than Nak PA-7, Marantz SM-7, Adcom GFA, Hitachi HMA-8500ii, etc. The amps I have on hand include Sumo Polaris, Luxman M-4000, and L-07M's. It's going to be interesting to be able to compare them with more amplifiers here soon.
Here's a photo of the Classe CA-150, along with a Cary SLP-30 preamp I had in the other day:
Blue Shadow
Waiting for Vintage Gear from this century
Thanks, That update holds a lot more weight than a simple it sounds better than the other **** I have been using. Hell most power amps sound better than piles and piles of common crap on AK.