Hello folks! I am not new to Audiokarma but have never visited or posted in this particular forum. My focus is generally vintage audio and Acoustic Research speakers are my favorite. Am also a Marantz fan with a number of models and have an HK Citation II as main amp. Recently I stumbled across an old guitar amp that I decided to snag. There are no musicians in our household, but do have many friends who are and it will be nice to have for someone to plug in during a visit. Also daughter Grace is getting married this Fall and we can use this as a PA for the reception!
As you can see the applique is off, but intact! I do have some knowledge and hobbyist skills for speaker rehab in general but this seems a bit more involved. I have done a bit of research and I do have the original schematic. The questions I have are pretty simple but didn't want to place any parts orders before getting guidance/confirmation from others more savvy on these matters. For example in the "parts list" on the schematic it calls out mica and ceramic caps for a couple of the components. I am by no means an engineer and do not possess the knowledge of actual differences in these things. I assume also that all caps likely should be replaced, but what else? Also in this case does brand or type effect the end result sound? I know this is a hotly debated topic in speaker circles but with this application differences may be part of the equation when replacing parts. I assume all dials and switches need a deoxit treatment but again looking for some confirmation before doing anything. I also have not plugged it in and am told it has sat in a closet for some 30 years prior to my ownership. The "seller" is a descendant of the original owner and has very little knowledge of it's history. Here are a couple more angles
All of my impressions are that this is a worthy candidate for a rehab. My mentality is usually bringing projects back to oem build as opposed to making mods. This unit sure seems to be all original which is always a great place to start. The driver in this cab appears to be well regarded in the research I have done.
and here is a photo of schematic. I will have this scanned, as well as the rest of the "Instructions" fold out that contains it for any that may be interested.
I have given a cursory look at the wiring by removing the back panel to expose. Looks like RCA tubes and I would suspect originals. The layout seems pretty easy to work on and does not look intimidating to me.
Look forward to any feedback from the community.
Geoff
As you can see the applique is off, but intact! I do have some knowledge and hobbyist skills for speaker rehab in general but this seems a bit more involved. I have done a bit of research and I do have the original schematic. The questions I have are pretty simple but didn't want to place any parts orders before getting guidance/confirmation from others more savvy on these matters. For example in the "parts list" on the schematic it calls out mica and ceramic caps for a couple of the components. I am by no means an engineer and do not possess the knowledge of actual differences in these things. I assume also that all caps likely should be replaced, but what else? Also in this case does brand or type effect the end result sound? I know this is a hotly debated topic in speaker circles but with this application differences may be part of the equation when replacing parts. I assume all dials and switches need a deoxit treatment but again looking for some confirmation before doing anything. I also have not plugged it in and am told it has sat in a closet for some 30 years prior to my ownership. The "seller" is a descendant of the original owner and has very little knowledge of it's history. Here are a couple more angles
All of my impressions are that this is a worthy candidate for a rehab. My mentality is usually bringing projects back to oem build as opposed to making mods. This unit sure seems to be all original which is always a great place to start. The driver in this cab appears to be well regarded in the research I have done.
and here is a photo of schematic. I will have this scanned, as well as the rest of the "Instructions" fold out that contains it for any that may be interested.
I have given a cursory look at the wiring by removing the back panel to expose. Looks like RCA tubes and I would suspect originals. The layout seems pretty easy to work on and does not look intimidating to me.
Look forward to any feedback from the community.
Geoff