Guys look at that:
Ultracurve
I'd like to make new coaxial input and use the R7 as input point. Anybody know wher do I take the ground from ?
Ultracurve
I'd like to make new coaxial input and use the R7 as input point. Anybody know wher do I take the ground from ?
blown fuse! Appears to be the PS
How about something more basic like blown fuse? I've isolated it to the PS; I'd go for replacing it. Read on.
Poked around the PS this am w/a DVOM. BTW:PSU 2496, PCB 213060 Rev D
Disconnected the PS from the switch & the DEQ circuitry. Pluged it in, turned it on, about 120VAC to PS molex.
Diodes showd about 500 ohms one way, "behaving correctly" the other. reconnect. Tighthed the ground connections. Not sure what else I could look at. reconnected the PS to switch*, turn it on, another blown fuse.* w/the DEQ circuitry disconnected
Any takers? thnx in advance for the help, tony
How about something more basic like blown fuse? I've isolated it to the PS; I'd go for replacing it. Read on.
Poked around the PS this am w/a DVOM. BTW:PSU 2496, PCB 213060 Rev D
Disconnected the PS from the switch & the DEQ circuitry. Pluged it in, turned it on, about 120VAC to PS molex.
Diodes showd about 500 ohms one way, "behaving correctly" the other. reconnect. Tighthed the ground connections. Not sure what else I could look at. reconnected the PS to switch*, turn it on, another blown fuse.* w/the DEQ circuitry disconnected
Any takers? thnx in advance for the help, tony
reply to post #64, dtd Aug 28, '05
can I use this PS in an in-modded unit? my original has "issues"
thnx tony
can I use this PS in an in-modded unit? my original has "issues"
thnx tony
lm4562 op amps
I'm going to agree with the other poster who tried the LM4562 op amps in his unit. I just wasted my time swapping out all of my 4580s and adding decoupling from both rails along with some electrolytics. Everything just wants to oscillate - the PCB layout on the analog side is horrible, so anything faster than the 5V/us 4580 isn't going to work. The engineers who designed this unit knew exactly what they were doing and were pinching pennies left and right. It's amazing how good it sounds right out of the box. I think the only way to get any serious high end sound from a DEQ/DCX2496 is to build dedicated input/output stages from scratch - the circuitry of the analog portion is plain old mediocre.
I'm going to agree with the other poster who tried the LM4562 op amps in his unit. I just wasted my time swapping out all of my 4580s and adding decoupling from both rails along with some electrolytics. Everything just wants to oscillate - the PCB layout on the analog side is horrible, so anything faster than the 5V/us 4580 isn't going to work. The engineers who designed this unit knew exactly what they were doing and were pinching pennies left and right. It's amazing how good it sounds right out of the box. I think the only way to get any serious high end sound from a DEQ/DCX2496 is to build dedicated input/output stages from scratch - the circuitry of the analog portion is plain old mediocre.
Hi folks!
Ancient thread I see, but since it seems to be alive I take my chances and post here 🙂
I'm now on my third DEQ2496. Hopefully I'll keep this one if it can be modded to an acceptable performance level. One problem with all DEQ's I've had (except for dying) is that they're noisy and have has a lot of mains hum. By 'a lot' I mean much more than any other equipment I own by a good margin (guitar effects, synths, mixers etc.), and certainly enough to make it unusable as a mastering or monitoring processor. In fact, I have a hard time understanding how it got all those good reviews.
Thus I'm wondering how other users a coping with that. I'm considering the power supply upgrade by stef1777, thinking that it might cure this problem. I'll probably also try some of the additional/changed bypass cap mods, before moving on to changing coupling caps and op-amps (although the report of oscillation above makes me reconsider the op-amp swap).
What do you reckon... New PSU == cure for hum? Other remedies?
DJ
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Ancient thread I see, but since it seems to be alive I take my chances and post here 🙂
I'm now on my third DEQ2496. Hopefully I'll keep this one if it can be modded to an acceptable performance level. One problem with all DEQ's I've had (except for dying) is that they're noisy and have has a lot of mains hum. By 'a lot' I mean much more than any other equipment I own by a good margin (guitar effects, synths, mixers etc.), and certainly enough to make it unusable as a mastering or monitoring processor. In fact, I have a hard time understanding how it got all those good reviews.
Thus I'm wondering how other users a coping with that. I'm considering the power supply upgrade by stef1777, thinking that it might cure this problem. I'll probably also try some of the additional/changed bypass cap mods, before moving on to changing coupling caps and op-amps (although the report of oscillation above makes me reconsider the op-amp swap).
What do you reckon... New PSU == cure for hum? Other remedies?
DJ
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If I used Optical In -> Room EQ -> Optical Out could I pass alot of the poorer areas in this EQ?
Digital in/ out
Digital in/ out with a DEQ2496 is a must have for any digital audio system. A direct out mod with the dac chip swapped to AK4395 gives an analog out which can rival the best dacs at any price. None of my 2496s hum.
Digital in/ out with a DEQ2496 is a must have for any digital audio system. A direct out mod with the dac chip swapped to AK4395 gives an analog out which can rival the best dacs at any price. None of my 2496s hum.
Just use it in digital mode and don't worry about it - if you have a good DAC.
If not, then modding the outputs is important.
If not, then modding the outputs is important.
Direct out
I run the output direct from the pins of the dac chip through a high quality coupling cap with no filters or active stages.
I run the output direct from the pins of the dac chip through a high quality coupling cap with no filters or active stages.
Are you running the stock PSU without hum, or is it a modded/exchanged one? I'd like to do the analog/audio mods, but the hum has to go first...
DJ
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I've never had any sort of noise problem - hum or hiss - with any of the 6 DEQ2496s that have passed through my hands. I suspect your hum is caused by something else in the chain, cable perhaps, or your unit is just plain faulty?
^ Thanks for the info. I'll investigate more closely. It'll most likely have a PSU mod soon anyway. I'll report back here if I find out anything useful.
DJ
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DJ
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No hum
I don't do much to the stock power supply and have never heard hum from any of 20-30 various 2496s I have worked on. The stock dcx has some hiss that the direct out mod gets rid of. You must have a faulty unit or some sort of grounding issue.
I don't do much to the stock power supply and have never heard hum from any of 20-30 various 2496s I have worked on. The stock dcx has some hiss that the direct out mod gets rid of. You must have a faulty unit or some sort of grounding issue.
^ Thanks! OK, I think we can safely say that we've established that there should be no excessive hum in these units, then 
DJ
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DJ
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I've replaced all the 12 electrolytic caps in the psu with Panasonic FC, Nichicon Muse, Silmic. The sound is more dynamic now.
I just bought a modified DEQ from Scott (sendler) to use it as a dac. Mine has no hiss or hum. I must also add that it sounds fantastic on the two systems I've put it in. Well worth the investment.
I'm mainly interested in adding the low jitter clock mod available from stef1777. Has anyone done that mod and seen any difference in sound?
I'm mainly interested in adding the low jitter clock mod available from stef1777. Has anyone done that mod and seen any difference in sound?
You might first ask him what specific sonic improvements come from that clock mod? 😉
Ditto that the direct out mod thru caps is fantastic, bypassing those opamps made everything so much more analog sounding 🙂
Hello, I'm considering on doing a mod on the deq2496.
I wish to:
-Install the AKM4395/6 (I understand the '6 does not need mods, and is drop in?)
+
-Bypass output stage, and run them through caps.
I am very new to this and will have a friend with a steady hand for soldering.
Can anyone provide me a link to a schematic of how where I would be installing the caps on the AKM4395/6? Ive seen a few links with multiple dayton caps from the akm out to the XLR out.
I guess I'm asking for a pin layout, and where the caps would be tied in.
Thanks so much everyone in advance.
I wish to:
-Install the AKM4395/6 (I understand the '6 does not need mods, and is drop in?)
+
-Bypass output stage, and run them through caps.
I am very new to this and will have a friend with a steady hand for soldering.
Can anyone provide me a link to a schematic of how where I would be installing the caps on the AKM4395/6? Ive seen a few links with multiple dayton caps from the akm out to the XLR out.
I guess I'm asking for a pin layout, and where the caps would be tied in.
Thanks so much everyone in advance.
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