Isn't that white glue a PITA to remove..
Yes, and you are right, I got a little lazy there didn't I?
It's not like I don't have enough acetone. Cheers,
James
Yamaha MX-1 Thread
- Thread starter Bratwurst7s
- Start date
Yes, and you are right, I got a little lazy there didn't I?
It's not like I don't have enough acetone. Cheers,
James
The 3 day delay between that last post and reporting success was because...
...well, you know that feeling? The one that you get after closing up an amp after a careful inspection, passing the dim-bulb-test, passing the protection test, and then you hook it up, turn it on, and get no sound? Like, Nada, Zero, No Damn Sound? That gut-punch feeling of wtf have I done NOW?
Yeah, so after putting the amp back on the bench and after the cool-off pause, I took it back apart on Wednesday to find out wtf. Really puzzled. I expected that I had forgotten to plug the boards back in or had broken a trace or wire somewhere. Really puzzled because I was not finding anything done wrong.
Until, yeah, until I found my mistake.
So, can you see the (double) mistake?
Cheers,
James
...well, you know that feeling? The one that you get after closing up an amp after a careful inspection, passing the dim-bulb-test, passing the protection test, and then you hook it up, turn it on, and get no sound? Like, Nada, Zero, No Damn Sound? That gut-punch feeling of wtf have I done NOW?
Yeah, so after putting the amp back on the bench and after the cool-off pause, I took it back apart on Wednesday to find out wtf. Really puzzled. I expected that I had forgotten to plug the boards back in or had broken a trace or wire somewhere. Really puzzled because I was not finding anything done wrong.
Until, yeah, until I found my mistake.
So, can you see the (double) mistake?
Cheers,
James
So, yeah, I somehow forgot to solder one end of not one, but BOTH of the input signal path resistors that I replaced. I must be getting old.
So, what do you think. Is that a Single Facepalm? No, I think not. That was both channels. Rates a Double Facepalm.
Well, the upside of this was that there was no catastrophic damage and no crippling monetary cost. Just a blow to my pride and 3 extra days.
Cheers,
James
So, what do you think. Is that a Single Facepalm? No, I think not. That was both channels. Rates a Double Facepalm.
Well, the upside of this was that there was no catastrophic damage and no crippling monetary cost. Just a blow to my pride and 3 extra days.
Cheers,
James
Now the amp is back in it's place in the system and passed the first sound check. Shortly I will be doing a more rigorous application of some Blues.
Cheers,
James
Cheers,
James
Some things run differently than planned. In this case Wife wanted some Kid Rock, so, no Blues tonight. For the record I had/have no problem with that. 
Having a 2 week interlude with using the M-70 as my power amp and then coming back to the MX-1 presents interesting contrasts.
The M-70 is a very nice amp. It's clean and clear, sounds very nice. I like it and always have liked it and it's little brother the M-50.
The MX-1 bests the M-70 in every way. It is clean and clear but has more presence. It has decidedly better channel separation and sound stage. It offers tighter and more defined midbass/bass. I was searching for one word to define the difference and came up with Authority. The MX-1 is a Beast and a Jewel at the same time. I sure am happy that it is back in the system and working well.
Cheers,
James
Having a 2 week interlude with using the M-70 as my power amp and then coming back to the MX-1 presents interesting contrasts.
The M-70 is a very nice amp. It's clean and clear, sounds very nice. I like it and always have liked it and it's little brother the M-50.
The MX-1 bests the M-70 in every way. It is clean and clear but has more presence. It has decidedly better channel separation and sound stage. It offers tighter and more defined midbass/bass. I was searching for one word to define the difference and came up with Authority. The MX-1 is a Beast and a Jewel at the same time. I sure am happy that it is back in the system and working well.
Cheers,
James
Isn't that white glue a PITA to remove..
Btw, while I had it apart I did address the white glue with acetone and cotton swabs.
Cheers,
James
Is this in reference to C18 1000µF/100v or the main filter caps? I still have not found replacements tor the main filter caps.
Cheers,
James
OK, a Nichicon LKG2A102MESABK would work for C18. Certainly it would be better concerning length than the UCC KYB that I used and better than the other 2 caps that I bought. On the other hand the KYB is rated at 105° (vs 85°) and has a 3.51A ripple current rating vs 2.75A.
https://www.mouser.de/ProductDetail/Nichicon/LKG2A102MESABK?qs=4lWw5qRttGJxW2aZG4FgYA==
Cheers,
James
https://www.mouser.de/ProductDetail/Nichicon/LKG2A102MESABK?qs=4lWw5qRttGJxW2aZG4FgYA==
Cheers,
James
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The new Nichicon " Great Supply's" are Nichicon KG type II CK's " Super Through".
You don't sleep much do you Dave?
In your experience would the KYB with 3.5A ripple rating be overkill in this position, compared to the LKG with 2.75A?
Cheers,
James
In your experience would the KYB with 3.5A ripple rating be overkill in this position, compared to the LKG with 2.75A?
Cheers,
James
OK, here is a public service announcement for other MX-1 owners.
When I decided to replace the binding posts / speaker terminals in my amp I first looked @ speaker-terminal.com to see if they had a set for our MX-1's, because they make sets for a lot of other Yamaha(+) amps and in my opinion have some pretty decent prices. I didn't see any on their website. But I wrote them anyway and asked if they had a solution. https://speaker-terminal.com/en/
They wrote back, on a Sunday no less, and told me that if I supplied them with measurements they could make a terminal set for me. Well, for my purposes if I had the amp apart to make accurate measurements it was just as easy to make a mounting plate myself. In fact making at least 1 mounting plate to confirm the accuracy of my measurements seemed mandatory before passing the info on to someone else. As seen above, in the end I made 3 plates and all 3 fit.
So at that point I had no further need to buy a finished terminal set. BUT. In the interests of audio friendlyness I did write speaker-terminal.com and provide them with my measurements, drawings and a link to this thread, purely in the hope that it would be useful to others.
Yesterday they answered my post. Now, please keep in mind that I have no connection or affiliation to these folks, and have no financial interest in this.
Anyway, they told me that they could make a set of terminal posts, consisting of 2 separate 4-post blocks with the same type of posts that I used, complete with pre-soldered connection wires, for the price of €43. Shipping inside the EU = €10 and outside the EU = €24.
So, anyone needing a speaker terminal set for a MX-1 should now be able to contact them and have a set made for what seems to me to be a pretty reasonable cost.
Keep in mind that they/you would be working with measurements that I made, but having installed my self-made block with no further adjustments needed I feel very comfortable with the accuracy of those measurements.
There you are. Again, I have no (0, Zero) financial interest in this, my intent is purely to make it easier for other members to maintain their amps.
Cheers,
James
When I decided to replace the binding posts / speaker terminals in my amp I first looked @ speaker-terminal.com to see if they had a set for our MX-1's, because they make sets for a lot of other Yamaha(+) amps and in my opinion have some pretty decent prices. I didn't see any on their website. But I wrote them anyway and asked if they had a solution. https://speaker-terminal.com/en/
They wrote back, on a Sunday no less, and told me that if I supplied them with measurements they could make a terminal set for me. Well, for my purposes if I had the amp apart to make accurate measurements it was just as easy to make a mounting plate myself. In fact making at least 1 mounting plate to confirm the accuracy of my measurements seemed mandatory before passing the info on to someone else. As seen above, in the end I made 3 plates and all 3 fit.
So at that point I had no further need to buy a finished terminal set. BUT. In the interests of audio friendlyness I did write speaker-terminal.com and provide them with my measurements, drawings and a link to this thread, purely in the hope that it would be useful to others.
Yesterday they answered my post. Now, please keep in mind that I have no connection or affiliation to these folks, and have no financial interest in this.
Anyway, they told me that they could make a set of terminal posts, consisting of 2 separate 4-post blocks with the same type of posts that I used, complete with pre-soldered connection wires, for the price of €43. Shipping inside the EU = €10 and outside the EU = €24.
So, anyone needing a speaker terminal set for a MX-1 should now be able to contact them and have a set made for what seems to me to be a pretty reasonable cost.
Keep in mind that they/you would be working with measurements that I made, but having installed my self-made block with no further adjustments needed I feel very comfortable with the accuracy of those measurements.
There you are. Again, I have no (0, Zero) financial interest in this, my intent is purely to make it easier for other members to maintain their amps.
Cheers,
James
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JakaKovacic
New Member
Hello James.
Very nice write up about re-caping your MX-1.
I recently purchased MX-1 too and I like to recap it. Is it possible for you to post part list like you did in M-70 thread?
Thank you in advanced.
Best
Jaka Kovacic
Very nice write up about re-caping your MX-1.
I recently purchased MX-1 too and I like to recap it. Is it possible for you to post part list like you did in M-70 thread?
Thank you in advanced.
Best
Jaka Kovacic
Hi Jaka and welcome to Audiokarma.
I did start a recap sheet last summer but didn't finish it. Give me a few days and I'll work on it and post it here.
Cheers,
James
I have a CX-1/MX-2 preamp/amplifier setup presently.
Not restored. We're talking 'long in the tooth' as far as years go. I followed the CX-1 thread regarding the serial numbers and realized I have a early CX-1, that being '93 as I recall. No idea on the age of my MX-2. I've thought about an MX-1 and search from time to time but just don't really need the extra power at this point. I'd buy one if I found a reasonable deal.
Does anyone have a suggestion for maintenance for these components? I'm not cheap. I just need someone I can rely on to do the proper maintenance. I'm somewhat at the point of finding other equipment and pulling these until I get them serviced.
Not restored. We're talking 'long in the tooth' as far as years go. I followed the CX-1 thread regarding the serial numbers and realized I have a early CX-1, that being '93 as I recall. No idea on the age of my MX-2. I've thought about an MX-1 and search from time to time but just don't really need the extra power at this point. I'd buy one if I found a reasonable deal.
Does anyone have a suggestion for maintenance for these components? I'm not cheap. I just need someone I can rely on to do the proper maintenance. I'm somewhat at the point of finding other equipment and pulling these until I get them serviced.
I'm very very happy with my CX-1 and MX-1. In terms of service and maintenance (the work involved and layout) I don't expect that there are any differences between the MX-2 and 1. The MX-1 was actually reasonably easy to work on. Unfortunately, from this side of the pond I can't help you with finding a tech if you are not in a position to do the work yourself. The obvious person that comes to mind however would be to PM Avionic about it.
Even without reading the SN of your amp(s) you can date them to within a few months by reading the date codes on the electrolytics. Both of my CX-1's are '93 production, one is a very early amp with obvious factory mods that were incorporated into the later unit.
Cheers,
James
JakaKovacic
New Member
OK, I'm posting a zip of the cap buy sheet here, and will edit a note into the first post that it is here.
The caps shown in the sheet are what I used in my amp with one exception, that being C39. I used a United Chemicon KYB there. A Nichicon LKG would be a better fit in the space available and that is what is entered in the sheet.
As always, there are a lot of different opinions concerning cap choices. I used what I prefer, and they worked very well. But there are many other possible choices out there. Also, Mouser availability is very spotty at the moment, with long lead times on some out of stock items.
Cheers,
James
The caps shown in the sheet are what I used in my amp with one exception, that being C39. I used a United Chemicon KYB there. A Nichicon LKG would be a better fit in the space available and that is what is entered in the sheet.
As always, there are a lot of different opinions concerning cap choices. I used what I prefer, and they worked very well. But there are many other possible choices out there. Also, Mouser availability is very spotty at the moment, with long lead times on some out of stock items.
Cheers,
James
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JakaKovacic
New Member
Thank you for your time to share this. I have some work to do now.
Will post my progress here.
Best
Jaka Kovacic
Will post my progress here.
Best
Jaka Kovacic