Latest recap and Upgrade amp - Yamaha M-70

[mech986]

Ghostberry, you might want to take some pictures outside and inside of the binding posts, that will show how they are secured or attached to the mounting panel. Usually, they are separate pieces that are mounted via screw threading on the posts and large opening nuts on the back side. Remember that they are soldered to a speaker or ground wire so even if you somehow turn them and they come loose, the wire needs to be cut and resoldered to the new post. You also have to see if there are individual holes for each post or a slot and mounting piece internally that holds the binding posts.

Since your unit is not a Yamaha but a Nikko Alpha II, you might want to start a new thread in Solid State forum where others with experience with Nikko products might be able to chime in.

 

[mech986]

We can use these pictures to understand how Nikko used this part. Appears to me that the binding posts are an assembly of molded parts on a common plate - the metal parts are inserted or molded in, so my guess is you can't take them off individually. the screws on either side of both of the binding post plates suggests that the plates are screwed in and held by screws. The interior shot also suggests that the only connections to the posts are the speaker wires, so makes removing the plates easier, but important to mark them.

As you can see from the bottom pic, there was a version (US?) that also had spring clip type posts - what type of posts depends on when it was made, and the country it goes to.

IMO, both the binding posts and input RCA's (also on a plate) should be relatively easy to unbolt, then unsolder (note and mark the wires carefully for Ch. A or B, and right and left + and -) or cut. Your bigger job is to find the right material (masonite, acrylic, plastic, etc.) measure, mark, cut, measure, fit, drill, assemble with binding posts, measure again, then solder, assemble, screw and lock down. Relatively simple if you've done it before, relatively simple if you take your time and think out the process.

 

[mech986]

this thread has links to the Nikko Alpha II service manual for adjustments, plus some nice pics on how the author rebuilt the amp with another DIY circuit, but rebuilt the speaker and input RCA panels, of course he's using just one set of in's and one set of outs. Its in Dutch, but Google can translate it reasonably well.

http://forum.zelfbouwaudio.nl/viewtopic.php?t=10195

 

[ghostberry]

Ghostberry, you might want to take some pictures outside and inside of the binding posts, that will show how they are secured or attached to the mounting panel. Usually, they are separate pieces that are mounted via screw threading on the posts and large opening nuts on the back side. Remember that they are soldered to a speaker or ground wire so even if you somehow turn them and they come loose, the wire needs to be cut and resoldered to the new post. You also have to see if there are individual holes for each post or a slot and mounting piece internally that holds the binding posts.

Since your unit is not a Yamaha but a Nikko Alpha II, you might want to start a new thread in Solid State forum where others with experience with Nikko products might be able to chime in.

Oh, okay I did not know there is a forum on different amps in general, but I will look. I do have photos but the computer I have upstairs is a win 7 and this win 10 and the option to add a photo is somehow not available or I would have put up a good photo of what you were saying...oh well but thank you for that information.

I will label every wire because I am dyslexic and I am bad with remembering stuff, but I know photos can help and that is one of the things I am going to do when I fix on these beasts!

 

[ghostberry]

We can use these pictures to understand how Nikko used this part. Appears to me that the binding posts are an assembly of molded parts on a common plate - the metal parts are inserted or molded in, so my guess is you can't take them off individually. the screws on either side of both of the binding post plates suggests that the plates are screwed in and held by screws. The interior shot also suggests that the only connections to the posts are the speaker wires, so makes removing the plates easier, but important to mark them.

As you can see from the bottom pic, there was a version (US?) that also had spring clip type posts - what type of posts depends on when it was made, and the country it goes to.

IMO, both the binding posts and input RCA's (also on a plate) should be relatively easy to unbolt, then unsolder (note and mark the wires carefully for Ch. A or B, and right and left + and -) or cut. Your bigger job is to find the right material (masonite, acrylic, plastic, etc.) measure, mark, cut, measure, fit, drill, assemble with binding posts, measure again, then solder, assemble, screw and lock down. Relatively simple if you've done it before, relatively simple if you take your time and think out the process.

That is the amp all but the last one at the bottom, my posts are exactly what you say, they are molded. I just saw a post on a guy using Acrylic from Home Depot and making his own plate, but I will take my time and I will mark those wires for sure. I have blk and red tape to put on which are positive and negative!

So, do you think I have to just remove the whole molded piece and try to pry off the parts? I think I will have to cut the wire for sure as I was trying to twist beyond what it is supposed to I noticed the wires started to move so I stopped and got great help from you and I thank you kindly for your time and effort I really will use this step to go at it and see how far I can go without damaging too much, but I have a good idea to how I can make my own and maybe put better quality posts! Thanks very much!

 

[ghostberry]

this thread has links to the Nikko Alpha II service manual for adjustments, plus some nice pics on how the author rebuilt the amp with another DIY circuit, but rebuilt the speaker and input RCA panels, of course he's using just one set of in's and one set of outs. Its in Dutch, but Google can translate it reasonably well.

http://forum.zelfbouwaudio.nl/viewtopic.php?t=10195

Yahoo! This is going to help my issue greatly and guide me to making 'less mistakes'!! Thanks again Mech this is kind of you for your time here! I do not know how to do those face things but I would do one bowing! ha ha

 

[ghostberry]

Sorry, I just saw the Google can interpret the site! I will try to figure that out now and see what it does! thanks again!

 

[mech986]

You're very welcome! To put in a "smilie" or emoji, in the reply box, there are some icons above it. Click the icon with the smilie face in it and you'll get a picture list of the smilies at the bottom of the reply box. click your cursor on where you want the smilie to go, then go down and click the smilie(s) you want. Its actually very easy.

 

[ghostberry]

I got the translater and read what he did!

Ha ha got the icon thing too thanks for the tip. He is putting in a torordial (cannot spell that parts name)! This guy must know design to take it to the bare case and rebuild!

Here is the one icon I was trying to find!

I got the idea of that site, so I will do to Home Depot and while trying to find a simple piece of material I will try to convince my fiance I need some new tools for this project!

 

[brutal]

Hi Brutal,

What is the stuff called or what area of home depot did you find the Acrylic? I wanted to ask if you just took out the old plate and just covered it with this nice piece? I have to figure out how to get binding posts off my Nikko Alpha II, I can turn them until they stop but I thought one can just keep turning them but they are not budging.

I am new to all of this and I am trying to find "how to get binding posts off an amplifier" but not luck. I was wondering if I can get the 'better' bigger diameter ones instead of the whimpy old version? I think there is space and when I saw this post I saw the nice work you did...wish I had the skill and know how.

I want to try to get an M70 a guy up here wants $500 CDN for one but I am not sure after I bought my Harman Kardon Citation 19 3 wks ago, I opened up the cover and found a smaller physical cap tied in parallel with the bigger can...so after finding out the new replacements were $265 bucks I could not believe what the cost of things are for vintage stuff...but I was told the rest of the parts if I so choose to replace are very little in cost...thank goodness!

The acrylic I used was located near all the window repair items - screens, metal mesh, etc. It may have actually been Lowes, I don't honestly recall.

The acrylic was only used as a cosmetic/insulating backing plate to keep the wire off the chassis. The Vampire wire posts I used had their own mounts that I was able to fit to the amp.

The "smaller" cap may be a film bypass cap and entirely legit.

 

[ghostberry]

The acrylic I used was located near all the window repair items - screens, metal mesh, etc. It may have actually been Lowes, I don't honestly recall.

The acrylic was only used as a cosmetic/insulating backing plate to keep the wire off the chassis. The Vampire wire posts I used had their own mounts that I was able to fit to the amp.

The "smaller" cap may be a film bypass cap and entirely legit.

Can I get a location where you got your Vampires from? I would love to get those ones as they are nice. I will have a peek at Lowes too. I found on Home Depot those 'wall' mount connectors! ha ha That would look pretty sad to Epoxy it to the back...making it ugly but MEAN!

 

[avionic]

http://www.vampirewire.com/

You should have started your own thread.

 

[ghostberry]

http://www.vampirewire.com/

You should have started your own thread.

What do you mean start a new one? I thought we just stick to here? Thanks for the link!

 

[brutal]

What do you mean start a new one? I thought we just stick to here? Thanks for the link!

To Dave's point. We try not to clutter up specific threads with too much unrelated info.

If the thread gets too off topic or If you have a new topic, start a new in the forum of your choice. thread. http://www.audiokarma.org/forums/index.php?forums/yamaha.173/create-thread

Spend a little time navigating the site, the different forums, and the buttons that may be available. I know most people not familiar with internet forums often land somewhere through search and just start replying to posts/threads. It's considered bad form to "threadcrap" by posting too much off topic chatter.

If you have a specific piece of gear or procedures you need help with, start a new thread, you'll probably get more participation too.

Nobody is trying to dissuade you from participating, we're all very welcoming, but we (especially me) tend to get somewhat pedantic about the threads we've taken the time to groom. Posting unrelated questions/repair advice in some of the sticky threads (like the literature thread) is considered uncouth.

FWIW, I always found a lot of my VampireWire stuff here at better rpices. http://soniccraft.com/

 

[brutal]

One more thing I would say about binding post upgrades - I often use a piece of Delrin as the mounting plate for the posts. You can search around in some other threads here for "delrin" and probably pick up some good tips and images. Order the larger pieces online. If you own or have access to a drill press or other shop tools, you can fabricate some pretty decent mounts. I've used my table saw and miter saw to build the plates, then mark and drill the holes for the BP. That often mounts to the inside of the back panel, then gets covered on the outside with some clear acrylic as seen in this thread.

Good luck with your upgrade!

 

[avionic]

I often use a piece of Delrin as the mounting plate for the posts.

I use black garolite (phenolic). I buy small sheets from McMaster-carr.

 

[avionic]

That smoked polycarbonate does look nice though.

 

[JoeMt]

Has anyone here compiled a parts list of the capacitors? I'm new to this but just picked up a m-70, c-70 and t-70. Previous owner claimed the amp would blow his circuit breaker. Hasn't done it at my home yet. I haven't found a great DIY yet.

I would like to recap it, switch to LED lights, replace the speaker connectors and fix the x2 cap (circuit breaker trip????) Where does one get the capacitors?

Thanks

 

[avionic]

Mouser,Digikey,Element 14(Newark),To name a few.

 

[JoeMt]

Mouser, Digikey, Element14....do you offer kits?