Dynaco A25 XL, Restoration Process

[bad_boo]

I recently got a hold of a pair of Dynaco A25, for $20cad at my local thrift store. After reviewing them online, I realized I got the XL version. H086 tweeter with SEAS drivers.
They are pretty beat up and I have started restoring them, and will go up to refinishing the cabinets and rebuilding the grills.



For now I have a couple of questions.
I have ordered a pair of 8uf MKP capacitors and waiting for them in the mail. However after some more digging on the A25s on AK, I've seen that the resistors are replaced as well. I have recapped before, but never changed resistors.
I see resistors of 15k, 3.9k and 2.2k ohms, and I believe the 55 means 5watts?
Is there any type of resistors that I should be looking up? I see on ebay says cement resistors, for example. Not sure if a generic resistor like this is good enough? or should I just leave them as it is.



Also, the speakers female connectors were all loose. Given the age of them, they just broke when I touched due to rust. So I had to hot glue them to hold them in place, just to sound test the drivers. And fortunately they all work well.
Any recommendation for parts or any tips for a work around to have the female connectors secured? (I haven't been able to find a female terminal that looks like these original ones).


*****On another note, I have also restored a pair of KEF 103.2 (that I use as my main), so I can't wait to compared them, as I have seen an AK thread about them too.

 

[avguytx]

I've owned 3 sets of A25's and one set of A10's and never changed the resistors "on purpose". I had one pair where a resister had crumbled and I replaced it with another basic one. Sure, you "can" replace them if you just want to but I don't feel you'll hear a big difference. Main thing is to make sure that control for them is as clean as you can get it for good continuity. Capacitor change was the biggest improvement and they are great sounding little speakers.

If you have the connections in places as best you can get them, I'd call it good. You can go to more extremes but that's your call. JB Weld holds stuff quite good but need to make sure it's a glue that has no conductive particles to it.

 

[JRhoBurton]

Agree with the above. I would also clean the tweeter level selector with Deoxit or similar.

 

[bad_boo]

Thank you @avguytx and @JRhoBurton for your advices. I didn't consider applying deoxit to the tweeter selector, so I'll be doing that.

I will also leave the resistors alone for now. Thanks pointing that out.

And will look into that type of glue if I find it. The hot glue works, as long as I'm not manipulating the drivers that often, and it's not conductive.

That way I don't make this project more complicated than it is.

 

[Bob in WI]

Thank you @avguytx and @JRhoBurton for your advices. I didn't consider applying deoxit to the tweeter selector, so I'll be doing that.

I will also leave the resistors alone for now. Thanks pointing that out.

And will look into that type of glue if I find it. The hot glue works, as long as I'm not manipulating the drivers that often, and it's not conductive.

That way I don't make this project more complicated than it is.

As I have a pair of A25s in storage that may (likely do) need to be refurbished, watching w interest.
Not sure which version I have but I'd assume they are similar. It will be a while before I get to them.
Please post how you make out.

 

[bad_boo]

As I have a pair of A25s in storage that may (likely do) need to be refurbished, watching w interest.
Not sure which version I have but I'd assume they are similar. It will be a while before I get to them.
Please post how you make out.

Thank you, absolutely, I will.

I currently have the cabinet in the garage, without the drivers, getting them ready for start refinishing them.
I will be posting my progress.

Thanks again.

 

[ivandezande]

I recently got a hold of a pair of Dynaco A25, for $20cad at my local thrift store. After reviewing them online, I realized I got the XL version. H086 tweeter with SEAS drivers.
They are pretty beat up and I have started restoring them, and will go up to refinishing the cabinets and rebuilding the grills.

View attachment 3083889

For now I have a couple of questions.
I have ordered a pair of 8uf MKP capacitors and waiting for them in the mail. However after some more digging on the A25s on AK, I've seen that the resistors are replaced as well. I have recapped before, but never changed resistors.
I see resistors of 15k, 3.9k and 2.2k ohms, and I believe the 55 means 5watts?
Is there any type of resistors that I should be looking up? I see on ebay says cement resistors, for example. Not sure if a generic resistor like this is good enough? or should I just leave them as it is.

View attachment 3083887

Also, the speakers female connectors were all loose. Given the age of them, they just broke when I touched due to rust. So I had to hot glue them to hold them in place, just to sound test the drivers. And fortunately they all work well.
Any recommendation for parts or any tips for a work around to have the female connectors secured? (I haven't been able to find a female terminal that looks like these original ones).
View attachment 3083888

*****On another note, I have also restored a pair of KEF 103.2 (that I use as my main), so I can't wait to compared them, as I have seen an AK thread about them too.

RGB5 indicates 5W. I would replace them, I don't trust old wirewounds. The SQPR line from TE or SQP from Yageo should be perfect, or whatever you prefer. Don't get them on eBay.....

I think epoxy would be a much better choice than hot glue.

 

[bad_boo]

RGB5 indicates 5W. I would replace them, I don't trust old wirewounds. The SQPR line from TE or SQP from Yageo should be perfect, or whatever you prefer. Don't get them on eBay.....

I think epoxy would be a much better choice than hot glue.

Great! thanks for the input. Would this 15R Resistor be a good one to go with. I guess 15R means 15k ohms, right?

Sure, I will get the epoxy, since I have the drivers out, so will be a good time to deal with them now.

Thank you!!

 

[ivandezande]

Great! thanks for the input. Would this 15R Resistor be a good one to go with. I guess 15R means 15k ohms, right?

Sure, I will get the epoxy, since I have the drivers out, so will be a good time to deal with them now.

Thank you!!

No. The K is tolerance, meaning +/-5%.
You need a 15 Ohm, 3.9 Ohm, and I can't read the last one.

 

[bad_boo]

No. The K is tolerance, meaning +/-5%.
You need a 15 Ohm, 3.9 Ohm, and I can't read the last one.

Sorry, I didn't realized about the other resistor being obstructed when I took the picture.
I think the third one should be 2.2 ohms (based on another A2XL cross-over I saw online).
Thanks so much again for your help and clarification on how to read the specs.

 

[ivandezande]

Sorry, I didn't realized about the other resistor being obstructed when I took the picture.
I think the third one should be 2.2 ohms (based on another A2XL cross-over I saw online).
Thanks so much again for your help and clarification on how to read the specs.

All good, you bet. These are gonna sound great when you're done.

 

[bad_boo]

All good, you bet. These are gonna sound great when you're done.

much appreciated

 

[bad_boo]

Just finished restoring the cabinets. Seems like the previous owners used them as a stand to hold their drinks and some other stuff, as seeing the marks on them..


Just before applying some black paint and Howard's restore-a-finish


They turn out a bit darker than I though it would be, but I think that hides better the damages on the top part.



I think they look fine like that, there are some imperfections on the surface that are not that obvious to see and the pictures didn't capture them. But it did a good job overall IMHO.
I also think they would looked better if I sand them and stain them. I did this to my KEF 103.2 and they turned out very nice. Probably I'll do this on summer, so for now should look good enough.

While I wait for the capacitors and resistors, I will look to rebuild the grills. I didn't get one of them, and the one that came with them is pretty bad, unfortunatley.
I have a black cloth that I didn't use for the KEF speakers, so I am debating if they would look good for the dynaco's, or if I would kill the originality on them lol

 

[bad_boo]

hmmm but if I had to buy the cloth, I guess this fabric would do.
edit: I think this type of cloth would better for the dynaco though. Maybe I should go for it.

 

[Bill S]

Just finished restoring the cabinets. Seems like the previous owners used them as a stand to hold their drinks and some other stuff, as seeing the marks on them..
View attachment 3086175

Just before applying some black paint and Howard's restore-a-finish
View attachment 3086174

They turn out a bit darker than I though it would be, but I think that hides better the damages on the top part.

View attachment 3086176 View attachment 3086177 View attachment 3086178

I think they look fine like that, there are some imperfections on the surface that are not that obvious to see and the pictures didn't capture them. But it did a good job overall IMHO.
I also think they would looked better if I sand them and stain them. I did this to my KEF 103.2 and they turned out very nice. Probably I'll do this on summer, so for now should look good enough.

While I wait for the capacitors and resistors, I will look to rebuild the grills. I didn't get one of them, and the one that came with them is pretty bad, unfortunatley.
I have a black cloth that I didn't use for the KEF speakers, so I am debating if they would look good for the dynaco's, or if I would kill the originality on them lol

I think they look fine. I wouldn't stain or darken them anymore. Maybe just sand the tops and reapply the oil. I always sand all the stain off being careful to not burn through the thin veneer, especially on corners. A nice, natural oil finish (no tint) is Waterlox. The more coats you add, the more gloss. The wood will darken as it absorbs the oil. I usually go 5-7 coats sanding lightly in between. I've used Waterlox on gunstocks as well.

 

[kwayde]

hmmm but if I had to buy the cloth, I guess this fabric would do.
edit: I think this type of cloth would better for the dynaco though. Maybe I should go for it.

I used this for my A-25's: https://www.ebay.com/itm/304581201050
There's more than enough to cover both speakers.

 

[bad_boo]

I think they look fine. I wouldn't stain or darken them anymore. Maybe just sand the tops and reapply the oil. I always sand all the stain off being careful to not burn through the thin veneer, especially on corners. A nice, natural oil finish (no tint) is Waterlox. The more coats you add, the more gloss. The wood will darken as it absorbs the oil. I usually go 5-7 coats sanding lightly in between. I've used Waterlox on gunstocks as well.

Great, Thank you! I will get this product for "phase 2" of this project, and follow the your directions.

I used this for my A-25's: https://www.ebay.com/itm/304581201050
There's more than enough to cover both speakers.

View attachment 3086523
View attachment 3086524

Perfect, I saw it on ebay as well and they really look nice. Thanks
By the way, yours turned out really really nice!!! I hope I can get mine close enough to yours, when I do the sanding and oil finish later on, on them.
***edit: thanks again, I just placed the order

 

[bad_boo]

Got the cabinets done. Just pending to do the grills when I get the fabric in the mail.


As mentioned before, I think they look fine, but refinishing them by sanding them and then applying oil will look better, as suggested above.

I also recapped them with 8uf MKP capacitors and new resistors.
Here's a before and after:


So I hooked them up and play some music. Absolutely, the sound is way better now. I noticed they are warm and good on bass.

Then I started comparing them with the KEF 103.2 I have. I would say I find them similar but the KEF have more details.

There is another thread in AK about KEF 103.2 VS DYNACO A25, that is worth checking, and I like all the comments.
I will keep checking and testing with different type of music and see their strengths. Like I said, even though the KEF are my preference, I like the dynacos, I like how warm they are, so they are a nice addition though.

 

[sinewaver]

For my A25 project, I found some fabric at Walmart that I think works out rather well. Cheap enough, about $7 a yard. These have been in my family since new, just passed around and finally back to me. They're kind of a reference benchmark. As in not as good as or better than.

 

[bad_boo]

For my A25 project, I found some fabric at Walmart that I think works out rather well. Cheap enough, about $7 a yard. These have been in my family since new, just passed around and finally back to me. They're kind of a reference benchmark. As in not as good as or better than.
View attachment 3088785

thanks!, hoping the fabric looks like this. I was not aware walmart has something like this.
Yes, they are nice speakers and it is something I will keep in my house or in the family. I have restored other speakers that I have given away with family and friends. Sharing the passion with them. .... My dad is looking forward to come over and give them test.