Cloned MQ60

[soundbrigade]

I found that I had written in a thread about triodes like 6CA10 and 50CA10 that I had a plan to build a clone oc the famous Luxman amp MQ60. However I have a small problem as I have found a number of schematics and I am a bit confused:
http://www.pastisch.se/beaver/amp_mq60.gif
http://www.pastisch.se/beaver/mq60-4.gif
http://www.pastisch.se/beaver/mq60c01.gif
http://www.pastisch.se/beaver/N-50CA10_003.gif
It will propably be the forst schematic I will work with. I have started to fix a chassis that will slightly remind of the original layout.



As soon as the Clementine is finished I will start with this one.

[kheper]

In the first and second schematics, the 6267 is correctly represented as a pentode. In the third, the 6267 is incorrectly represented as a triode.

In the third schematic, the NFB does not seem to go anywhere. Best to get rid of number 3.

The NFB loop (most use a 3.3K resistor) also varies among the schematics.

The fourth schematic uses cathode bias, while the rest are fixed bias.

[soundbrigade]

And I have planned for fixed bias - my first amp with this config. I will go for #1.
I have the EF86 and possibly even the 6DT8 (or equivalents).

Found 50CA10 on OH Boy!, else I have 7 of them, two or three bad apples.

[kheper]

The first schematic shows a Sansui Sw-30-8 output. I think Luxman used Sansui's. What impedance is the Sw-30-8? 8K?

On ebay for big bucks, look at the Hashimoto transformers. They made the original Sansui's outputs.

[battradio]

And I have planned for fixed bias - my first amp with this config. I will go for #1.
I have the EF86 and possibly even the 6DT8 (or equivalents).

Found 50CA10 on OH Boy!, else I have 7 of them, two or three bad apples.

At that Price i think i would try 6GT5's wired as triodes
http://www.ebay.com/itm/One-Fully-Teste ... 20a75e4017

[Brik]

Hi Magnus,

In your list of schematics only the second schematic depicts the original MQ60.

I found that I had written in a thread about triodes like 6CA10 and 50CA10 that I had a plan to build a clone oc the famous Luxman amp MQ60. However I have a small problem as I have found a number of schematics and I am a bit confused:
http://www.pastisch.se/beaver/amp_mq60.gif　<- this is a modified clone
http://www.pastisch.se/beaver/mq60-4.gif <- this is the original MQ60
http://www.pastisch.se/beaver/mq60c01.gif <- this is a modified clone
http://www.pastisch.se/beaver/N-50CA10_003.gif <- this is a modified clone
It will propably be the forst schematic I will work with. I have started to fix a chassis that will slightly remind of the original layout.

Here is one of the later revisions:


It sounds like a swell project.
Have fun!

[soundbrigade]

I started this some 6-7 yeras ago; ordered two tubes from the Netherlands for an SE-amp, got one broken and managed to get another pair and have the amp up and running.



Then came the GREAT ( ) idea of building a Luxman clone and that's when I ran into some problems - no tubes to make a PP-design, and I only had three



This photo was taken with tubes and transformers mounted in an attempt to shoot my stuff with an attractive backdrop. At this session, one or two more tubes broke (internal structure came loose).



Eventually I bought four new ones and after resting a few years I am prepared again.

[kheper]

Found 50CA10 on OH Boy!, else I have 7 of them, two or three bad apples.

http://www.goodcomponent.com/index.html

http://www.goodcomponent.com/Shuguang%20Tube.html

50CA10 = $62.00/each

This merchant is said to be reliable, but the chassis they sell look better in the picture than in "real life".

The lowest priced Shuguang 813 around:
813A = $40.80/each

4, 8, and 9 pin Teflon sockets for $5 a pop.

RCA cables $2.70

Transformer covers from $9 - $13.

[soundbrigade]

I got sockets and tubes (4+) but I could consider getting another pair just in case.

I've beens truggling with metal sheets, cutting and bending them i perfect shaope and fit, today.

[soundbrigade]

F*CK the metal work!!!! I ordered a Hammond chassis today. That leaves me with the drilling and cutting the various holes.
When the Clementine is ready I will fix this one.

[Geek]

Do you have your fingers still?

Cheers!

[kheper]

Think these caps are any good? Too bad they are only 400V.

http://www.goodcomponent.com/MKP.html

[soundbrigade]

Do you have your fingers still?

Cheers!

I will show you waht I did yesterday, after work. I was alone in the workshop with cutter for metal sheets and a "bending machine". ALWAYS look twice before pressing the button.
The problems have been misadjustments or aesthetical mishaps.

[soundbrigade]

Joe Stroud: Maybe the caps are OK, but I have an allergy to anthing marked "audiophile". At least they are cheap.

[soundbrigade]

Almost ON ...
The chassis is driled, filed, sawed since a long time. Some minor adjustments had to be made.





Transformers, choke, tube sockets and the biggest filter caps (470u/250V)