Audible illusion L1

Anyone who owns this L1 model should be familiar with the 4 dip switches on the circuit board, i bought a used L1 with no manual,i read this information somewhere and i dont recall that those switches are for cutting in and out the capacitors on the output signal path,can someone confirm? also if the switches are in off position are those caps being bypass? or the other way? All info's and responses will be appreciated, thanks in advanced!
The 4 dip switches modify sonics of the preamplifier's line stage. Once the preamp has been broken in we recommend that they be switched to the OFF position. Regards, Jerry/AI
Thanks jerry!
Jerry, the L1 sounds good as stock, any possible improvement beside tube rolling? any mods (coupling caps, chassis damping. etc...) or anything that is possible to bring the L1 to the next level? any suggestion will be greatly appreciated
Pepericoz, We mfg.the L1 from 1994-2003 and made no updates to the design during this period. However, the 5mF/300v polypropelyne caps could be updated to newer versions. Also, replace two of the four HVB+ 100mf/400v, radial-lead,Panasonic electrolytic caps with Panasonic 220mf/400v caps. (The first two caps closest to the front. Not the 3rd & fourth caps with the bypasses). This will improve the preamps dynamics. However I suggest you have this work done by a competant technician. Regards, Jerry
Thanks for all the suggestions, can these caps be purchased thru AI? if it can, what caps (brands)do you offer for the 5mF/300V polypropelyne? thanks again

PS; by the way i have applied soundcoat damping sheet thru out internal chassis also top and bottom cover ( ofcourse not blocking ventilation hole ) and have experienced better detail and tighter bass, what do you think?