Blue Shadow
Waiting for Vintage Gear from this century
There are those here that own these amps and I'm wondering what condition they are in as far as tube compliment and modifications done to the amps. For those that don't own these amps but want to participate, let's discuss the other mid-powered tube amps with a good following. A question about these at the end of this post.
For the modifications, there are those needed to make the amp operate in UL or Triode mode based on the documentation. They are different mods. Additionally, these amps can be improved with some other mods and I'm wondering what folks have done in this arena, too.
I'll start.
Backstory, swapped a Hafler DH-200 kit I built for these back in the day. Used them until I couldn't bias and balance the 8045G tubes in them. Unfortunately, I didn't buy a bunch of tubes, $15 back then to keep them running. So I put them in the double box and stored them for decades.
After finding the web and time to deal with the amps, I contacted folks that own the amps and got a copy of the Luxman modification manual to allow these amps to be converted to use the 6550/KT88. I did the mod and no joy. Gadget47 dropped by and found the problem straight away. The manual does not say to connect the choke to the tube resistor installed to the terminal block. Joy. Sound great.
I have stock MB3045 mono amplifiers converted to operate in the UL mode. One has gotten hot on the board and I did some board repairs, replaced the resistors, mounting them above the board (below as the component side is down) and installed replacement caps for that location. I have also installed a ICL, in-rush current limiter.
I have not installed a new RCA or modded the AC inlet or bypassed the input level control. These can be improved. Since the GE tube is too expensive for some and the Winged C is no longer in production, I have a set of Tung Sol KT88s in these that perform well. In an amp listening session, these walked all over the competition, Crown PSA-2, Hafler DH-200, Citation 22, McCormack DNA-1.
Post about your Luxman tube amps.
One other thing is which midpowered tube amp would you want? You get your pick, but since this is just a hypothetical question there is no value in the amp chosen. So picking the one with the highest resale will net you a big fat zero so pick it by experience, looks, sound quality or whatever reason you want, even name brand since a few have strong name recognition. Sound quality would be the choice for selection but many haven't heard these amps. Let's keep this to the 30-60 watt range.
Marantz 8b
McIntosh MC30
McIntosh 225
Luxman MB3045
Dynaco ST70
Citation II
and others, I guess.
For the modifications, there are those needed to make the amp operate in UL or Triode mode based on the documentation. They are different mods. Additionally, these amps can be improved with some other mods and I'm wondering what folks have done in this arena, too.
I'll start.
Backstory, swapped a Hafler DH-200 kit I built for these back in the day. Used them until I couldn't bias and balance the 8045G tubes in them. Unfortunately, I didn't buy a bunch of tubes, $15 back then to keep them running. So I put them in the double box and stored them for decades.
After finding the web and time to deal with the amps, I contacted folks that own the amps and got a copy of the Luxman modification manual to allow these amps to be converted to use the 6550/KT88. I did the mod and no joy. Gadget47 dropped by and found the problem straight away. The manual does not say to connect the choke to the tube resistor installed to the terminal block. Joy. Sound great.
I have stock MB3045 mono amplifiers converted to operate in the UL mode. One has gotten hot on the board and I did some board repairs, replaced the resistors, mounting them above the board (below as the component side is down) and installed replacement caps for that location. I have also installed a ICL, in-rush current limiter.
I have not installed a new RCA or modded the AC inlet or bypassed the input level control. These can be improved. Since the GE tube is too expensive for some and the Winged C is no longer in production, I have a set of Tung Sol KT88s in these that perform well. In an amp listening session, these walked all over the competition, Crown PSA-2, Hafler DH-200, Citation 22, McCormack DNA-1.
Post about your Luxman tube amps.
One other thing is which midpowered tube amp would you want? You get your pick, but since this is just a hypothetical question there is no value in the amp chosen. So picking the one with the highest resale will net you a big fat zero so pick it by experience, looks, sound quality or whatever reason you want, even name brand since a few have strong name recognition. Sound quality would be the choice for selection but many haven't heard these amps. Let's keep this to the 30-60 watt range.
Marantz 8b
McIntosh MC30
McIntosh 225
Luxman MB3045
Dynaco ST70
Citation II
and others, I guess.
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