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Dynaco A25 Questions

Isaac C.

Isaac C.

Cat Hoarder
Hello everyone, I recently picked up a nice pair of Dynaco A25s and have a couple of questions. Firstly, does anyone have a suggestion as to what to use to remove stains from the white grill cloth? Finally, I might potentially recap these and was wondering if the drivers are in anyway "sealed" to the cabinet with silicone or some other form of adhesive before removing them? Thanks in advance!
 
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If you decide to go with new cloth, I have a great way to attach it. I used this method on some large Advent's and it worked fantastic and was easy:

On the backside of the grille frame where the original cloth was attached, you apply 2 coatings of contact cement, waiting 15 minutes or so between coats. Let it dry completely for an hour or 2 or 5.
Place your fabric on the counter top, front face down, then set your grille frame centered on it, glue side up toward you. Take an old iron (I bought one at Goodwill for $5), fold the cloth over the glue along one long side and run the hot iron over the cloth/glue. The iron will soften the contact cement enough to securely attach the cloth within seconds. Do the same along the other long side, stretching/ pulling the cloth tight across the front of the grille. Try to make sure the cloth thread/pattern runs straight along the frame edge.
Glue the short sides down in the same fashion. Stretching the fabric as much as possible. You trim and glue the corners last. You will have to experiment on making the corners. Note how the original cloth was attached and try to duplicate that. If you don't like how a part glued down, just reheat and lift the cloth to retry.

Before I applied the contact cement, I ran masking tape down each side about 1/2 inch in from the edge. This kept the glue neat and keeps it off any velcro.
And after the cloth is glued down, you trim it by running a blade along the masking tape edge for a straight and neat edge.

Let it set overnight. Spritz the new cloth with water and then dry it with a hair dryer to shrink it tighter. Don't apply too much heat to the cloth for fear of scorching it. I think the shrink method works on natural type cloth.

Jef
 
My A25 woofers were glued with something. Lift the woofer slow and carefully. It did pull up some particle board shards. I smeared/pressed wood epoxy along the particle board lip to ensure a smooth and level surface. But that may not be critical because it is a semi ported enclosure.

Another thing I did is glue blocks of 3/4 inch wood to the underside so that the woofer mounting screws bite good. With these particle board panels, the woofer screws can only be reinstalled a couple of times before stripping out. Same with my KLH's and Advents.

Jef
 
Here’s a source for replacement grill cloth. Cleaning the old stuff can be difficult. https://www.123stitch.com/cgi-perl/itemdetail.pl?item=59-135X

If you take out the woofer screws, just use a flat blade screwdriver to pry up the edge of the woofer. It’s sealed with some black tarry goop but comes out pretty easily.

I highly recommend cap replacement with film or Mylar. If I recall it’s a 5 or 8 uf depending on the version you have. It took mine from good to great.
 
Thanks for the replies! In regards to the cloth, I applied some new fabric glue on the frame where the cloth folds over. Im going to try to clean the cloth the best I can very carefully. I really like the original cloth, however, If I am unable to clean it I'll end up recovering the grills. The local Hobby Lobby has some white burlap that looks very similar to the original if I decide to opt for new cloth.

Also, has anyone tried attaching velcro on the corners of the grill and inside the cabinet itself for easy removal of the grills.

As far as the woofer, thats what I thought, the woofer appears to have black adhesive, but I just wanted to hear from others before removing them. Additionally, does anyone prefer a specific brand for the replacement capacitors? PartsExpress has Dayton or Solen capacitors in 5.1μF, in addition to Audyn and Jantzen in 4.7μF. I would prefer to stay with replacements under $10 each. Thanks!
 
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Fabric glue instead of contact cement works great. I also used burlap from Hobby Lobby on my Boston Acoustics A150 grilles. I also used Velcro to attach the grilles.
 
Isaac C. said:
Also, has anyone tried attaching velcro on the corners of the grill and inside the cabinet itself for easy removal of the grills.
Click to expand...

Yes, I did this.

I used small, pre-cut, self-adhesive Velcro squares.

Works perfectly!
 
Thats what I was thinking of doing. I managed to remove all the stains with the exception of one small stain with Oxiclean stain remover. I let it sit for 10 minutes and gently rubbed the cloth with a warm towel.
 
Did your A25s have the badges?

dynacoBadgeA.jpg
 
Though the veneer is in excellent shape, I'll likely strip the old finish, sand, re-stain, and wax them with Howard's Feed N Wax in the next week or so.
 
Those (glue-on types) should be fine (easier access to components), as the screw-in logo type keeps the grill secure. Interesting decision Dynaco made in the securing of the logo(?).

One of mine was missing too and when I went to pull the grill off I didn't realize what was holding it up from coming off. I've heard some horror stories about grill and logo damage along with particle board coming off with the grill if you're not careful. I avoided this by seeking info here on AK. :D

I stayed stock with my logos and found another screw-in pair. YMMV

Good Luck, sounds like you're headed in the right direction!
 
Isaac C. said:
Thanks for the replies! In regards to the cloth, I applied some new fabric glue on the frame where the cloth folds over. Im going to try to clean the cloth the best I can very carefully. I really like the original cloth, however, If I am unable to clean it I'll end up recovering the grills. The local Hobby Lobby has some white burlap that looks very similar to the original if I decide to opt for new cloth.

Also, has anyone tried attaching velcro on the corners of the grill and inside the cabinet itself for easy removal of the grills.

As far as the woofer, thats what I thought, the woofer appears to have black adhesive, but I just wanted to hear from others before removing them. Additionally, does anyone prefer a specific brand for the replacement capacitors? PartsExpress has Dayton or Solen capacitors in 5.1μF, in addition to Audyn and Jantzen in 4.7μF. I would prefer to stay with replacements under $10 each. Thanks!
Click to expand...
The first time I recapped these I used cheap electrolytics, then redid them a year later with Mylar and they were wayyy better. So as long as you’re using Mylar or poly I think you’ll be happy.
 
IMHO, you might be overthinking the re-finishing and sanding part of these. Your A25s look really good.

I hit mine quickly with 0000 steel wool with the Howards Restoration stuff and then used the Citrus Feed 'n Wax,...they cleaned up quickly.

EDIT: Shame that the grill on the left looks stained :no:. The one on the right looks great! :bigok:
 
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