Very cool what you did to those old speakers. Working on gear and upgrading parts can be a lot of fun. I replaced all of the internal parts in my speakers with better quality same value caps, replaced the sandcast resistors with Mills, the inductors with high quality air core inductors, the internal wire with silver plated occ copper, and rhodium plated all copper binding posts. I did 1 speaker at a time so I could compare them, and the upgraded parts definitely made a big difference for the better. More clarity, separation of instruments, better bass response, etc., etc. I absolutely loved my speakers before and even more now. Thanks for the vid! 🔊🎶😊
Thanks. I like keeping my vintage stuff vintage. It's all in what you want to accomplish. If you're looking for a change from the original, then I say go for it! It's all fun!
At 7:50 mention is made about aging electrolytic capacitors measuring higher in capacitance than when they were new. My understanding is that this is due to increased internal resistance in series between the plates of the capacitor. It forms an RC filter, and due to the increased R, it then takes longer for the C to charge to the same level. The net effect is that an LCR meter reads BOTH a higher value of C and also displays the increased R. A theoretically perfect capacitor would have zero ohms of R, but that is impossible in the real world. Hope that helps you electricroo. Keep up the good work.
Thanks for the information on what you did to bring your Mach Two Speakers back to life. I just replaced the foam surround in my father-in laws old speakers. I will check my capacitors while I have them apart!
My Mach 2 speakers , when I was younger , I blew the super tweeters & midranges , a few times , making the internal light glow bright ! Later I put the best replacement speakers in it I could find , Woofers too , they still Jam ! Not like my Sansui 9900’s , but they still impress
I just picked up a pair of the Mach twos that needed to be saved and restored. Unfortunately they were in a smokers home, 🤮. I’m reforming the mids but had to replace the woofers as they were different and neither were OEM. Picked up two 15” woofers that supposedly fit these Mach twos at Simply Speakers. 75 oz magnets (W-1500). People were really raving about them, and finding the OEM 15s was a challenge. I replaced the caps on a pair of 1971 pioneer CS-88a’s and you really can hear the imagining and instrument separation much better with new caps. Just would like to see about getting something closer to the original screws for the woofer instead of the dam Sheetrock screws I found in both woofers (hate when people do that). Like you I enjoy restoring these vintage speakers, it’s really not hard, and it’s a great little hobby with a ton of reward. 👍🏼. And my ears are 61 years old, not working the way they once did, but I can still appreciate the fidelity.
I took some working Bose 501s and made my own frankenstein 501s lol. I put all new drivers and brand new crossovers. The result? They sound so much better than the original 501s. They get louder with great detail and the low end output is incredible. I also have a pair of Vega d5s and added new off brand woofers because originals were no good. I also added brand new crossovers. Again, the result is better than the original.
Thanks for uploading, I just refoamed my mach 2s that I've owned since new as my parents bought them for my birthday in the early 80s. I am going to measure and replace the caps, probably like you have with maybe a nicer bypass cap on the mids and tweeters. Anyway just curious if you messed with the ferrofluid in the tweeters. It's funny that I'm nervous to hook them up as I don't want to cook anything nor be dissapointed if they don't sound right. One thing for sure these speakers will get you 90 percent of the way to much more expensive speakers and rattle the foundation of your house in the process.
I didn't touch the tweeters. Don't be disappointed with the woofers. It will take a lot of hours or sustained high volume to break them in after re foaming. I broke mine in cranked up with some yard parties out here using the 100w per channel SS amp that I built. They settled in nicely. It would be nice if GR Research ever re-designed a crossover for those. I'm sure Danny would do it but you'd have to send him a set and it would be very expensive!
@@electricroo A few years ago I reached out to dany at gr research and he said he'd never even heard of them before. I'll definitely break in the woofers, but was most curious about the tweeters. I've heard from speaker builders that the butt cheek tweeter is a winner for sure, happy to hear that you might not have heard a dropoff in the highs due to dried up ferrofluid.
@@koprcord5338 I can help you abit with this. I recently picked up a pair of Mach ll's and upon initilal listening I could tell the tweeters were less that 100%. I could hear output from them but even with the L-pad all the way clockwise, I could barely hear them. It was the exact same scenario with a pair of older B&W speakers. I dissasebled the tweeter (easy) and cleaned all the old ferrofluid from the VC on the tweeter and the VC gap in the magnet. Once I put them back in the speakers they sounded as they should. I'm not too worried abot frying them as I dont play them very loud. You can get replacement FF on the internet and replace it if you so choose. I'm good with it the way it is. Hope this helps!
@@johnmitchell4769 thank you for the feedback. Nobody else has really talked about taking the tweeters apart. I still have not as if I screw it up they are not easy to replace. With that said, did you have to desolder the diaphragm leads or anything to get access to the voice coil? Just want to be prepared. Also what was your method for cleaning out the old fluid. Thank you.
The crossover parts are really cheap. 5% NP metal poly caps, wire wound resistors and air-core inductors will elevate those speakers well beyond factory. They will take the speaker from pretty good to great. The stock caps (if you must) at least use quality electrolytics like Bennic or Black gate. The generic stock caps would be lucky to be within 30% of value, highly resistive and degraded after so many years. Old caps (to me). sound murky and dull, as I have compared worn stock electrolytic to 5% metal poly.
Yep, they are cheap. But they are matched perfect to the amp I built for them and retain their 70 - 80's vintage sound. Sometimes I think we get to carried away with trying to improve things instead of keeping examples of what the engineering of the day was designed to sound like. Such as restoring vintage equipment. Sometimes the intent is just to restore to original as close as possible.
