A600 Audio Filter Always On!

h0ffman · 01 September 2013, 22:46

Hope you guys can help. Basically I was trying to setup my A600 and A1200 as a DJ setup using the PT-1210 software I wrote (as previously shown by Akia, hi mate).

I finally got around to setting it up today and the first thing I noticed is the A600 sounds like the filter is on. Direct comparison between the A600 and A1200 playing the same tune definitely sounds like it thats the case.

I know for a fact the code is disabling the filter (standard PT-Replay). Also the A1200 just simply sounds like it should!

Firstly has anyone else ever had this problem?

Secondly, there is a thread on here somewhere which says I can hard disable it by removing the Q341 transistor. I've located it (far right side of the mobo, last in a line of 3)

Has anyone ever done this mod?

Any info would be awesome.

Cheers

voyager · 01 September 2013, 22:52

Did you recap the 2 audio caps? because music will sound dull with old caps.

h0ffman · 01 September 2013, 22:57

nope, bugger.. that will be what the problem is then as there seem to be leakage! F@*K sticks!

h0ffman · 01 September 2013, 23:06

looks like new caps then

demolition · 02 September 2013, 01:08

Does the power LED changes intensity when you enable/disable the filter (or just reset the machine)? Because they are hardwired together.

h0ffman · 02 September 2013, 20:44

yep. definetly does dim when changing the filter. There was crap on the motherboard right around the capacitors so its gotta be that.

Gutted

demolition · 02 September 2013, 20:53

Sounds very likely yes. But when you take them out, be sure to check all the connections before soldering in the new ones as it is likely that something's broken.

Just replacing the caps with new ones will probably not fix the problem.

h0ffman · 02 September 2013, 20:54

Bugger, I need a professional to fix this then

sad times.

pandy71 · 02 September 2013, 21:03

Quote:

Originally Posted by h0ffman

Bugger, I need a professional to fix this then

sad times.

connect U15 (LF347/TL084) pins 8 and 5 for Right Channel and pin 14 and 3 for Left Channel - if audio sounds like Filter OFF then issue is located somewhere around FET transistors (for example issue with U28 MC1488, CIA etc).

john1979 · 03 September 2013, 00:26

Also going by my already recapped A600, even with the filter off the audio is a fair bit muddier/duller than an A1200. The difference is not noticeable on a TV but with a Hi-Fi it's obvious.

h0ffman · 05 September 2013, 14:26

Seems I've found a sollution, a friend of mine is going to do a like for like A600 swap with me. He needs it more for ASCII art than sound

btw all this is leading up to Sundown Demoparty this weekend..... i'll post another thread

pandy71 · 05 September 2013, 21:35

Quote:

Originally Posted by h0ffman

Seems I've found a sollution, a friend of mine is going to do a like for like A600 swap with me. He needs it more for ASCII art than sound

btw all this is leading up to Sundown Demoparty this weekend..... i'll post another thread

This will not fix problems with dry/leaking caps.

ElectroBlaster · 06 September 2013, 19:29

I suspect the same here with an A600 Rev1.5. Audio caps and some around the power input all smell fishey and look a bit off!

Im going to send over to the guys at Amigakit, not sure when but re-capping is something I will not even attempt without the correct stuff!

Those two audio caps are so close to the keyboard ribbon slot... how can somebody replace them without causing damage?

voyager · 08 September 2013, 13:34

Quote:

Originally Posted by ElectroBlaster

I suspect the same here with an A600 Rev1.5. Audio caps and some around the power input all smell fishey and look a bit off!

Im going to send over to the guys at Amigakit, not sure when but re-capping is something I will not even attempt without the correct stuff!

Those two audio caps are so close to the keyboard ribbon slot... how can somebody replace them without causing damage?

Take of the top part of the keyboard connector, use some heat protective tape on the bottom part of the keyboard connector, use some flux, and tada.

h0ffman · 08 September 2013, 22:16

well I tested another working A600 at the weekend and finally found at that basically, the a600 has shit sound circuits compared to the A1200. While at the demo party someone overheard me and said, "I have a spare A1200, you want it? I don't want any money for it" :O so I have two now, and they both sound great.

Aparently its well knows the 600 sound isn't great and there is a way to make it better, but I dont need to now

kipper2k · 08 September 2013, 22:29

There is a way to change the gain on the A600 audio circuit similar to the hack for the A500, it can be increased or decreased by swapping out 2 resistors of different value

01 September 2013, 22:46	#1
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	A600 Audio Filter Always On! Hope you guys can help. Basically I was trying to setup my A600 and A1200 as a DJ setup using the PT-1210 software I wrote (as previously shown by Akia, hi mate). I finally got around to setting it up today and the first thing I noticed is the A600 sounds like the filter is on. Direct comparison between the A600 and A1200 playing the same tune definitely sounds like it thats the case. I know for a fact the code is disabling the filter (standard PT-Replay). Also the A1200 just simply sounds like it should! Firstly has anyone else ever had this problem? Secondly, there is a thread on here somewhere which says I can hard disable it by removing the Q341 transistor. I've located it (far right side of the mobo, last in a line of 3) Has anyone ever done this mod? Any info would be awesome. Cheers

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01 September 2013, 22:52	#2
voyager The show must go on. Join Date: Dec 2010 Location: Alkmaar Nederland Posts: 269	Did you recap the 2 audio caps? because music will sound dull with old caps.

01 September 2013, 22:57	#3
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	nope, bugger.. that will be what the problem is then as there seem to be leakage! F@*K sticks!

01 September 2013, 23:06	#4
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	looks like new caps then

02 September 2013, 01:08	#5
demolition Unregistered User Join Date: Sep 2012 Location: Copenhagen / DK Age: 43 Posts: 4,190	Does the power LED changes intensity when you enable/disable the filter (or just reset the machine)? Because they are hardwired together.

02 September 2013, 20:44	#6
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	yep. definetly does dim when changing the filter. There was crap on the motherboard right around the capacitors so its gotta be that. Gutted

02 September 2013, 20:53	#7
demolition Unregistered User Join Date: Sep 2012 Location: Copenhagen / DK Age: 43 Posts: 4,190	Sounds very likely yes. But when you take them out, be sure to check all the connections before soldering in the new ones as it is likely that something's broken. Just replacing the caps with new ones will probably not fix the problem.

02 September 2013, 20:54	#8
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	Bugger, I need a professional to fix this then sad times.

03 September 2013, 00:26	#10
john1979 Registered User Join Date: Jun 2012 Location: UK Age: 44 Posts: 748	Also going by my already recapped A600, even with the filter off the audio is a fair bit muddier/duller than an A1200. The difference is not noticeable on a TV but with a Hi-Fi it's obvious.

05 September 2013, 14:26	#11
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	Seems I've found a sollution, a friend of mine is going to do a like for like A600 swap with me. He needs it more for ASCII art than sound btw all this is leading up to Sundown Demoparty this weekend..... i'll post another thread

06 September 2013, 19:29	#13
ElectroBlaster Junior Member Join Date: Mar 2002 Location: Exeter, Devon, UK Age: 49 Posts: 1,708	I suspect the same here with an A600 Rev1.5. Audio caps and some around the power input all smell fishey and look a bit off! Im going to send over to the guys at Amigakit, not sure when but re-capping is something I will not even attempt without the correct stuff! Those two audio caps are so close to the keyboard ribbon slot... how can somebody replace them without causing damage?

08 September 2013, 22:16	#15
h0ffman Registered User Join Date: Aug 2008 Location: Salisbury Posts: 744	well I tested another working A600 at the weekend and finally found at that basically, the a600 has shit sound circuits compared to the A1200. While at the demo party someone overheard me and said, "I have a spare A1200, you want it? I don't want any money for it" :O so I have two now, and they both sound great. Aparently its well knows the 600 sound isn't great and there is a way to make it better, but I dont need to now

08 September 2013, 22:29	#16
kipper2k Registered User Join Date: Sep 2006 Location: Thunder Bay, Canada Posts: 4,323	There is a way to change the gain on the A600 audio circuit similar to the hack for the A500, it can be increased or decreased by swapping out 2 resistors of different value

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