The Fisher XP-1 Questions
- Thread starter RobertKC
- Start date
Reviewing notes for what I missed... That "guaze" over the tweeter does not look like I can remove it without doing some cosmetic damage. I can't see much of anything inside other than a 1 1/2" silver metal piece in the center of the cone. They play clear in a signwave test with no audible issues. I don't feel a need to open them up. Since they refer to them as "Free Edge". My guess is there is no typical surround attaching the cone to side of the basket.
Again, trying to make sure I did not miss anything and sure enough this comment rose to the top! On the insulation: I did put the old stuff in individual trash bags but I did not throw them away... yet! I was planning on replacing the insulation but I have had several people (outside of this forum) say that keeping the same weight, density and volume is crucial to keeping them sounding original. I am getting close to buttoning these up so my current thought was just to put the original insulation back. I could weigh the original and match that with new polyfill. The other thing I have heard is that I should match the fact that the original treatment left about a third of the cabinet sides, top and bottom bare. My sensibility says that I should apply some treatment to the bare surfaces (other than the baffle) but I am not an acoustician. Am I just overthinking this?
I'm no Einstein here but from what I've gathered the composition of the fill is just one more variable. Each of the commonly encountered materials (fiberglass, polyfill, recycled denim, rock wool) has different characteristics and just weighing the content in fiberglass and jamming that same weight of some other stuff in there is not likely to give you equal results.
Thanks Einstein! LOL - well yesterday I put one speaker back together - making it as close to original as I could. I did "fluff" the old insulation wearing gloves and a respirator. Installed the original warped cone midrange. Sealed up each driver with speaker gaskets. Push test on the woofer shows great results on the seal. I couldn't stop myself from testing the single unit and in a word - WOW! Complete sign wave sweep revealed no issues! It clearly reproduced tones from 30hz to about 13000hz and probably higher as I am sure my ears don't work well above 13000hz. Then I put on a little progressive jazz and holy crap! These 60+ year old speakers ROCK! If the second one comes to life with equal results these will definitely move the to main listening room! Replacing my new $2500 Totem Bison's with a REL sub. Other than a fair amount of my labor time I will have under $300 in these and the majority of my time has been in cosmetic repairs to the cabintes! I am still working on the final touches to the cosmetic work so I am not going to post the final before and after photos now. Here are a couple of the re- insulating photos. So excited to finish this project up!
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Those are super cool. that grill is fantastic, and the build q on those is great. I find a lot of vintage speakers that get a bad rep, its often due to badly out of spec crossover capacitors. other then that i wouldnt do much to them. also, the capacitors you pulled out are likely pcb oil filled, which is toxic, so I wouldn't leave them where kids can get at them etc. I find a lot of times, running a vintage speaker with am additional modern tweeter seperate, results in a surprisingly modern sound. I have a set of vintage advents, which are one of my fav speakers ever, and I run them with a set of monsoon ribbon speakers from a computer setup. the ribbon drivers fill in any of the gaps the advents might have.
They really do sound nice! I used the German Audyn caps to replace the old matching the the 4uF spec on the originals. Everything else is stock. Not sure if my set was an original pair or not as it felt like neither one had any modification from stock but they definitely used different caps and the woofers look to be slightly different with the obvious being the dust caps. The backs of the woofs did look identical. Also the rheostats were slightly different. As for the old caps, at this point I have them on my work bench because I love the look of old tech! I like to do folk art and I was thinking of adding them to a sculpture. They are not leaking anything, should I worry? What about the warped cones on the mids - they seem to sound fine but that warped cone has to be coloring their output. tgmartin has I think correctly identified them as being very similar to the mids in the AR-2's. At some point I if I find a nice clean vintage pair I may make that swap. Otherwise they will stay stock! The only thing left at this point is I am going to apply a vintage griill cloth to the back side of that plastic grate. That is what they would have had originally. The icing on the cake is that I do have the original THE FISHER badges! The cabinets are truly beautiful after about 20 hours of my refinishing work. When the grills are finished I am going to post before and after pics.
Left and right both test out! I have not put them in action yet so the next question is do they sound the same? I can't wait to have put them in use! Thanks for all of the helpful dialog over the past weeks.! Looking good! Here's hoping #2 goes as well and they sound the same. Sometimes less IS more.
I collect a lot of vinatage speakers, stuff like 50s klh, advent etc. In the 50s a lot of times the companies went with whatever stock they could find for parts. this is back when these were hand made in the us. I read somewhere about Henry Kloss of KLH shopping at military surplus sales for crossover parts. lol So, often the same model might have different parts inside, depending on production date. So, i wouldnt worry about slight differences between them. And yes, the old oil caps are cool looking. Your only concern would be if it was leaking. from what i have read, the old oil caps tend to be sealed super well, so it may not be an issue. Pcb oil is pretty bad stuff if it leaks though, its pretty toxic. Ge almost got sued out of existence for dumping pcbs in the hudson river, and they have been dredging for like 25 years to try and fix it. Its not like a battery though, if it is sealed well, it is likely that it will stay that way. I would just save a search on fleaBay for " ar-2 mid", otoh, it probably affects the sound a bit, but not terribly. And yes, i would love to see pics. they are a super cool design. I love fisher tube stuff, always wanted to try a set of their speakers.
I had a setback last night! After completing and testing everything I went to work on the final step of getting the grills restored I did a prefit and found that my gasket thickness would not allow the grills to sit properly. At that point I went back to the workbench to remove the drivers and address that issue and I damaged one of the midrange cones! It was minor crack in the paper cone. I have applied some PVA glue and I will test tonight but now I feel like I should really just find a less warped AR-2 replacement. On the original issue I was addressing, I do have a question. The grill clearance I am dealing with is very tight! I need the gasket depth to be less than 1/8" to keep the drivers from pushing against the grills. the original gaskets were super thin - maybe a 1/32". I need to keep an airtight seal but I am thinking of eliminating any paper gasket material and only using a very thin application of speaker caulk. Does this make sense? Is the paper gasket providing any real value? Finally - will I even be able to find a AR-2 midrange that does not have a warped cone? They all seem to be about the same.
Good luck finding an AR2 5" that isn't warped. I suppose it's possible that these things became misshapen from the get-go because of the fiberglass wedges being stuffed behind the cones. I don't believe I've seen a high resolution picture of a new driver at the time of production to verify this, but ... I have a few of these and they're ALL warped and very brittle.
I'm using the cheapest "window seal" self adhesive gasket tape whenever possible. It comes in various sizes, only sticky on one side, reinforced with some glass fiber and compresses down to almost nothing but seals the spots where it's required. I guess if the wood surface is chewed up enough and there are REALLY large gaps of missing material this stuff may not work so well but it sure makes it easier to disassemble and service later.
I'm using the cheapest "window seal" self adhesive gasket tape whenever possible. It comes in various sizes, only sticky on one side, reinforced with some glass fiber and compresses down to almost nothing but seals the spots where it's required. I guess if the wood surface is chewed up enough and there are REALLY large gaps of missing material this stuff may not work so well but it sure makes it easier to disassemble and service later.
You have been a great help! Thanks Just installed some of that foam gasket and I am back in business. My repaired mid seems to be fine but I did order a set of nicer set of AR-2s that I found on ebay. I have not decided if I will install the original or wait for the replacements to arrive next week. The new ones were warped but a lot less than mine. The last step will be to get new grill cloth adhered to the back side of the plastic grate. Hope to work on that tomorrow. So ready to put these in my listening room to see how I feel about them in a real world test. Updates coming soon!