LS1 is better
The LS2 circuit's line stage is very similar to LS1 which is simpler and single ended only. The LS2's way of doing balance circuit is terrible and adding unnecessary parts and gain stages. I rather use single ended like the LS1. If interested, here's the LS1 entire set of schematics. if you want balance input, it's better to use an input bridging transformer a la Jensen. Same goes for output. The LS1 is a terrible sounding preamp anyway. There are better line stage circuits out there, even hybrid ones. Don't be mislead by reputation alone.
The LS2 circuit's line stage is very similar to LS1 which is simpler and single ended only. The LS2's way of doing balance circuit is terrible and adding unnecessary parts and gain stages. I rather use single ended like the LS1. If interested, here's the LS1 entire set of schematics. if you want balance input, it's better to use an input bridging transformer a la Jensen. Same goes for output. The LS1 is a terrible sounding preamp anyway. There are better line stage circuits out there, even hybrid ones. Don't be mislead by reputation alone.
Last edited:
thanks for replying. Drirectdriver and also thanks for PDF files.
actually my friend day after yesterday bought a audio research ls2b for sound testing and now he is totally mad for the impressive sound with his Peavey 60+60 classic tube amp+Audio Research LS2B+chario syntar 200 tower.in the past we have test several Audio research pre amp but sound was not impressive or not matching with system. we have experience over electronics so we are make a decision to copy LS2B.
LS2B preamp part is complicated over LS1
actually my friend day after yesterday bought a audio research ls2b for sound testing and now he is totally mad for the impressive sound with his Peavey 60+60 classic tube amp+Audio Research LS2B+chario syntar 200 tower.in the past we have test several Audio research pre amp but sound was not impressive or not matching with system. we have experience over electronics so we are make a decision to copy LS2B.
LS2B preamp part is complicated over LS1
Last edited:
What you posted is just the negative side of the balance circuit, the phase inverter, and has no gain. The actual gain stage is hybrid with half 6DJ8 cascaded from a FET input which is similar the LS1 circuit, picture number 2 below.
The full circuit can be found in ARCDB, of course. Here are the three diagrams of the circuit and they did not include the parts list, hence your inquiry.
Not my idea of elegant circuit but enjoy your project anyway!
The full circuit can be found in ARCDB, of course. Here are the three diagrams of the circuit and they did not include the parts list, hence your inquiry.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Not my idea of elegant circuit but enjoy your project anyway!
Last edited:
The LS2B sounds much better than the LS1. I owned each for several years. However, since this is a DIY forum, I would add that it is fairly easy to build a linestage that sounds considerably better than either of the ARC units. Think single-stage 12B4 with CCS plate load and a top-quality output coupling cap. Once you hear that, you won't want to listen to either of the ARC preamps.
I don't have experience with the LS2 but I have owned several LS1s and they all sound terrible. The reason I have them is that since the LS1 is not a collector's item it's perfect for gutting so I can reuse the chassis and power supply and use a different circuit. Cheaper than building from scratch and looks better than anything I can build! The only reason to keep an LS1 is for modification.
hi friends good news today we do copy all 6 band resistor values one by one plus others semiconductors positions, we take snap both sides and superimpose tracks over the pcb of gain stage with circad pcb maker software. it is very easy task for us. we doing cross check by circuit diagram and loaded pcb side by side.original pcb has built in xlr output stage we decide to omit that's part or avoiding unnecessary complicacy rather then we have test sound with unbalanced inputs and outputs and we are fully satisfied.
one thing have little bit problem for original fets and mosfets part number.all semiconductors part number removed and color coded.we have hints and previously we have repaired audio research others models with our knowledge
and they played well although any friends if have part number or have better solutions please mention me. hope we will be success and offcourse i will share all my works for my audio lovers.
one thing have little bit problem for original fets and mosfets part number.all semiconductors part number removed and color coded.we have hints and previously we have repaired audio research others models with our knowledge
and they played well although any friends if have part number or have better solutions please mention me. hope we will be success and offcourse i will share all my works for my audio lovers.
Last edited:
- Status
- Not open for further replies.