Thankyou both for the input. I will try line 6;s website  and a local music store that I am in good standing with to try to get the schems. As for fixing the power amp section, I would prefer to get the effects or "preamp" out of the line 6 if possible. The amp has great effects but I was never happy with the tone of the amp.  There is no way to get  nice highs or presence from the amp so I am hoping with using the power section of the tube vox I may get more high end bite. Thank you again and I will get the schems if possible.

                                 John DullebawnIII

sorry for the period of time it took me to get back to you, the job got cancled anyway. My brother passed away thursday and of course we are all at a loss. I decided to get back on the horse here to get my mind off of my loss. As for sympathy for the musical jam I was in, I was not asking for any. The headphone out was the only problem with the amp and that happened 1 1/2 years ago when my neice kicked the headphone cable while it was plugged in and cracked the pcb at the output jack, I did have a tech look at it and was told all else was fine with the amp and it seemed to be as it worked great for the last year and a half. This power section  problem just happened out of no where. I do take good care of my gear, just in this case a $280 dollar fix on a $300 amp to get a headphone out working didn't seem like the best move. If you are willing to offer some help here that would be great as cash is tight and I love the tone from the tube section of the vox anyway. I will try and find the circuit if I cant find any online is there a way I could take close ups of the pcb;s on my amp? Thanks

if the amp is stereo you can blow the side that you disconnect the speaker on

Hello everyone I was checking the internet for a possible fix for a problem I have, and ran across some smart people here so I was hoping I may get an answer. I have a time sensitive problem. I have a line 6 spider IV 120, the power amp died and the headphone out has not been working for awhile. However  I can still write patches so the effects side seems to be fine. My band is playing this weekend and I have alot of fairly complex patches wrote as we are a cover band that plays alot of different types of music. I really need my amp this weekend. I have a nice vox amp that sounds great, what I am hoping is if its possible to add an effects loop, send-recieve jacks for the effects section of the line 6 to run to the vox so I can use the effects of the line 6 and power of the vox or, disconnect the power amp section of the line six and where the signal leaves the effects to go to the line 6's power amp section disconnect it and soldier a 1/4 jack as an effects out to run the effects to the vox amp's input. So basically I need the effects of the line 6 togo to the vox amp. This model does not have any I/O's other than an mp3 input that works and the headphone out that does not work. I do know enough to do this work if I have a layout or discription of what needs to be done, I just dont have the knowledge to figure out the signal path :-). Thankyou all that offer help as this is a very important job for me and my band and money is so tight atm I cannot buy a new effects pedal. Thanks again
                                                                John Dullebawn