Hi, i bought a pair of samson db-500A powered 15 inch 500 watt speakers used of craigslist a while ago, used em for a fiew shows and love em.
there biamped, the tweeter and 15 each have there own amplifier.
PROBLEM:
I was mixing at home the other day and noticed that one of the 15's in one speaker wasnt playing anything, i was only getting sound out of the tweeter, so i turned the speaker off, then back on again and the 15 kicked back in. the same thing happened again a day later but this time it didnt kick back in as soon as i restarted it, so left it off for a while, turned it back on and the 15 was playing music again.
turned it on this morning, and the 15 played music for one song, i played another song 10 mins later and my 15 isnt playing anything again!!
I have never heard of or seen a problem like this before, could it be a loose connection to the amp for the 15?
i have shows coming up this month so i need my FOH mains badly.
any and all help is much appreciated.
Basscrime.
there biamped, the tweeter and 15 each have there own amplifier.
PROBLEM:
I was mixing at home the other day and noticed that one of the 15's in one speaker wasnt playing anything, i was only getting sound out of the tweeter, so i turned the speaker off, then back on again and the 15 kicked back in. the same thing happened again a day later but this time it didnt kick back in as soon as i restarted it, so left it off for a while, turned it back on and the 15 was playing music again.
turned it on this morning, and the 15 played music for one song, i played another song 10 mins later and my 15 isnt playing anything again!!
I have never heard of or seen a problem like this before, could it be a loose connection to the amp for the 15?
i have shows coming up this month so i need my FOH mains badly.
any and all help is much appreciated.
Basscrime.
Hi guys.
Having a couple of issues with a pair of DB500a's.
In one speaker, it sounds like the 15 has gone - in the other, it sounds like the tweeter has gone..
So, after having read this forum, I decided to take them to bits to have a look.
First, I took the front off to look at the cones to check the connections.
They were okay.
Then I took the backs off both, and swapped them to see what would happen. Lo and behold, the problems got swapped too...
Although the 15 inch fired up intermittently with a fiddle with the volume control...so, I now have a couple of circuit board-type things out of the speakers - I have heard both tweeters working, and both 15 inch cones working, so I am happy that those parts at least are not damaged.
However, how do I go about fixing what appears to be the actual issue - the circuit boards are either dirty or something is wrong.
How do I check, how do I repair?
Any and all help much appreciated.
Having a couple of issues with a pair of DB500a's.
In one speaker, it sounds like the 15 has gone - in the other, it sounds like the tweeter has gone..
So, after having read this forum, I decided to take them to bits to have a look.
First, I took the front off to look at the cones to check the connections.
They were okay.
Then I took the backs off both, and swapped them to see what would happen. Lo and behold, the problems got swapped too...
Although the 15 inch fired up intermittently with a fiddle with the volume control...so, I now have a couple of circuit board-type things out of the speakers - I have heard both tweeters working, and both 15 inch cones working, so I am happy that those parts at least are not damaged.
However, how do I go about fixing what appears to be the actual issue - the circuit boards are either dirty or something is wrong.
How do I check, how do I repair?
Any and all help much appreciated.
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So you have dete4rmined that the board in one amp will not drive the woofer, and the board from the other amp will not drive the tweeter, is that correct? And by testing, you have foud that both tweeters and both wooferes are in fact functional, yes?
Each board has an individual problem. It COULD be as simple as a dirty connections, but I'd wager it is more likely each board has an electronics circuit problem. Do you have and know how to use a soldering iron and a multimeter? And can you change components on a circuit board?
Each board has an individual problem. It COULD be as simple as a dirty connections, but I'd wager it is more likely each board has an electronics circuit problem. Do you have and know how to use a soldering iron and a multimeter? And can you change components on a circuit board?
Yes - bearing in mind that the knobs and switches are still attached to the board, and that turning the 'line in' volume control up and down will produce intermittent sound from the woofer.
Yes.
Yes - there are no clicks, fuzzy sounds - nothing out of the ordinary from either woofers or tweeters on both cabs (depending on which board is used!)
I think my best case scenario is looking like one dirty contact (woofer, since it comes on if you play with the knob), and one possible electrical contact
Yes
Not quite so much...
not something I have done before, but will give it a go if I know which components are u/s
cracked solder joints can also be an issue pull out a magnifying glass and and inspect where pins from a connector are joined to the board, also try tapping the assembly while running at low volume and see if it cuts in and out a sure sign of a crappy /broken contacts.
in basscrimes' case i'd be looking for bad cap's, interstage and decoupling, to me the hint there is the volume fade over time.
in basscrimes' case i'd be looking for bad cap's, interstage and decoupling, to me the hint there is the volume fade over time.
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Hi new, to the forum.
I thought I'd like to share my experiences repairing of a pair in Samson DB500A's.
When I bought these from Thomann 8 years ago, after the first week one of the cabs lost it's bass.
With no fuse blown or fault led's on display, I thought it might be the speaker, but that checked out ok.
Back it went to where it came from and they exchanged it no problem.
Eight years later and with no issues up to this time, again no bass from the speaker.
Now out of warranty I thought I'd try and repair it myself, especially now the circuit diagram is out there on the web.
With no fuses blowing and no led's displaying a fault, a look at the diagram shows the two tweeter and woofer relay coils are connected in parallel.
This means that if either the tweeter or woofer isn't producing sound but one of them is, and the speakers have been proven ok, it can only mean that the corresponding relay to that tweeter or woofer isn't opperating.
How can that be, relays never go wrong do they..
Put your ohm meter across the relay coils and you should get approx 150 ohms ie two 300 ohm coils in parallel, I was getting 300 ohms indicating an open circuit relay coil. As the tweeter was still working, this must point to the woofer relay.
The woofer relay in question is a DONG WOO DW321-12volt,
and tweeter relay is a DONG WOO DW323-12volt.
Tracking a replacement relay led me to Farnell CPC and they do a better quality FINDER 44.62 dpdt one.
The original Dong Woo woofer relay uses 10 Amp contacts wired in parallel, and the Dong Woo tweeter ralay 5 Amp contacts wired in parallel.
The FINDER 44.62 is again 10Amp and is the perfect replacement and will suffice in both cases.
The tweeter relay however will need the two unused switch tags fatigued off and removed to allow it to fit on the circuit board.
Probably the most difficult part of the repair is getting out the faulty relays without damaging the board.
You're going to need a solder sucker and lots of patience.The printed circuit tracks on these are pretty good though, and I was able to get them out without damaging anything.
The repair was totally sucessful on this cab but the other one lost it's tweeter only a week later, again a faulty relay. I could'nt believe it, two faulty relays in a week and I've looked after these cabs.
So I decided to change all the relays in both cabs with the FINDER 44.62 ones.(Farnell order code 1169304) about £20.00 for all four relays, inc vat and delivery, and of course lots of labour.
Good luck.
I thought I'd like to share my experiences repairing of a pair in Samson DB500A's.
When I bought these from Thomann 8 years ago, after the first week one of the cabs lost it's bass.
With no fuse blown or fault led's on display, I thought it might be the speaker, but that checked out ok.
Back it went to where it came from and they exchanged it no problem.
Eight years later and with no issues up to this time, again no bass from the speaker.
Now out of warranty I thought I'd try and repair it myself, especially now the circuit diagram is out there on the web.
With no fuses blowing and no led's displaying a fault, a look at the diagram shows the two tweeter and woofer relay coils are connected in parallel.
This means that if either the tweeter or woofer isn't producing sound but one of them is, and the speakers have been proven ok, it can only mean that the corresponding relay to that tweeter or woofer isn't opperating.
How can that be, relays never go wrong do they..
Put your ohm meter across the relay coils and you should get approx 150 ohms ie two 300 ohm coils in parallel, I was getting 300 ohms indicating an open circuit relay coil. As the tweeter was still working, this must point to the woofer relay.
The woofer relay in question is a DONG WOO DW321-12volt,
and tweeter relay is a DONG WOO DW323-12volt.
Tracking a replacement relay led me to Farnell CPC and they do a better quality FINDER 44.62 dpdt one.
The original Dong Woo woofer relay uses 10 Amp contacts wired in parallel, and the Dong Woo tweeter ralay 5 Amp contacts wired in parallel.
The FINDER 44.62 is again 10Amp and is the perfect replacement and will suffice in both cases.
The tweeter relay however will need the two unused switch tags fatigued off and removed to allow it to fit on the circuit board.
Probably the most difficult part of the repair is getting out the faulty relays without damaging the board.
You're going to need a solder sucker and lots of patience.The printed circuit tracks on these are pretty good though, and I was able to get them out without damaging anything.
The repair was totally sucessful on this cab but the other one lost it's tweeter only a week later, again a faulty relay. I could'nt believe it, two faulty relays in a week and I've looked after these cabs.
So I decided to change all the relays in both cabs with the FINDER 44.62 ones.(Farnell order code 1169304) about £20.00 for all four relays, inc vat and delivery, and of course lots of labour.
Good luck.
I bought my units back in 2005.
Got great service and alot of duty out of them,
Sound was on par with Eon s (allthough Alot heavier!! 30kg+)
the problem I had within two years was a bass speaker lug that vibrated loose, I hot glued that on both the speakers to keep it secured.
Last month I used the speakers for the first time after storage in a shipping container in our yard.
Alot of my equipment got tarnished on connecting surfaces. !!!
due to condensation and dampness
Mixer lost channels (tarnished)
yamaha P3200 (xlr connections tarnished)
InterM Pa1500 (stuck in protection mode)
Samson db 500a one module blown
I know I must have taken greater care in testing on power up but that was al at once at the gig! There is a forum on InterM I'll post the pics there.
And the innards of the db over here.
Comments welcome.
Got great service and alot of duty out of them,
Sound was on par with Eon s (allthough Alot heavier!! 30kg+)
the problem I had within two years was a bass speaker lug that vibrated loose, I hot glued that on both the speakers to keep it secured.
Last month I used the speakers for the first time after storage in a shipping container in our yard.
Alot of my equipment got tarnished on connecting surfaces. !!!
due to condensation and dampness
Mixer lost channels (tarnished)
yamaha P3200 (xlr connections tarnished)
InterM Pa1500 (stuck in protection mode)
Samson db 500a one module blown
I know I must have taken greater care in testing on power up but that was al at once at the gig! There is a forum on InterM I'll post the pics there.
And the innards of the db over here.
Comments welcome.
Other than a moldy smell. Not visible moisture damage or rust
I am on the trail of the weakest link.. the relays.
The module that is working have the Relays clicking on at power on. Red -> Green light
The faulty module (not blowing fuses with no sound) does not click on at relays
the green light does come on after few seconds like I said without audible click.
Interesting is the different transformer serials and little appearance differences.
Thanks again Wiseone you set me on the trail. Im going to source the 10A Replacement relay, remove the relays and have it tested.
I am on the trail of the weakest link.. the relays.
The module that is working have the Relays clicking on at power on. Red -> Green light
The faulty module (not blowing fuses with no sound) does not click on at relays
the green light does come on after few seconds like I said without audible click.
Interesting is the different transformer serials and little appearance differences.
Thanks again Wiseone you set me on the trail. Im going to source the 10A Replacement relay, remove the relays and have it tested.
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Hello, thought I would try and help here.
I'm a tech and have have similar issues with these, nearly always the bass driver that stops working.
First the relays will fail , and I mean all will fail, only a matter of time, even the hf relays.
Change them all out RS do them quite reasonably priced.
Also R97. 47k will also fail. It's grossly under wattage. If it's a little green looking rather than blue, again only a matter of time.
Change for at least a 1Watt type.
This can be done without removing the motherboard but the daughterboard will need to be removed.
Just undo the two screws on the brass posts and remove the board.
Hope this helps.
I'm a tech and have have similar issues with these, nearly always the bass driver that stops working.
First the relays will fail , and I mean all will fail, only a matter of time, even the hf relays.
Change them all out RS do them quite reasonably priced.
Also R97. 47k will also fail. It's grossly under wattage. If it's a little green looking rather than blue, again only a matter of time.
Change for at least a 1Watt type.
This can be done without removing the motherboard but the daughterboard will need to be removed.
Just undo the two screws on the brass posts and remove the board.
Hope this helps.
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