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Old 7th December 2003, 01:39 PM   #111
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Default Pioneer DV-563A

I have been looking at this fairly cheap DVD player for a while to use as a transport and because it would do DVD-A and SACD. BestBuy sent me a 10% off coupon, so I braved the masses of holiday shoppers and bought one. Opened it up as soon as I got home and here is what I found:

Picture of output board and ps

Switching power supply- there may be room to add a small linear ps for the analog stage, or heck, an external power supply, very high end

One BB DSD1791 dac and two BB DSD1702EG dacs, two 4560 opamps. It looks like the 4560s are buffers/filters for the 1702s, but I thought the 1791 needed an ouput buffer, its outputs are differential?

I may just do some dampening to the chassis and leave the guts alone, I will use it mainly as a transport for my Perpetual Technologies P-3A dac. I already have a good SACD player on my main system, I was just a little curious about DVD-A.

--David
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Old 7th December 2003, 04:19 PM   #112
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Wasn't "dampening" making something wet ? I learnt that in case of vibrations you can spend time "damping" the vibrations....
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Old 7th December 2003, 04:19 PM   #113
Morse is offline Morse  United States
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Hi David;

Thanks for the pic of the Pioneer DV563A's interior! I've thought about buying one myself....

The first thought, before you even look at electronics work, is that the boards can easily be remounted on rubber gaskets or o-rings on either side of the screw holes. The second thought is that the output caps look like they're easy enough to find, assuming those connections on the bottom left of the pic are to the audio and video outs. These can be damped with a single dab of rope caulk along one side (not the top, since those are designed to blow "up" through the top in the event of a catastrophic failure. I wasn't able to find the clock crystal in the pic, but it might just be on the other side of the main board. It's another structure that really benefits from some kind of damping (Jon Risch maintains that the "sandbag tweak" as described at his site is best overall, since blu-tak and rope caulk have internal resonances - I'm just a nervous nellie about allowing sand inside my player!).

I'm not sure how much difference it will make, but I'm planning on buying a sheet of thick vinyl sheeting of the type used for damping auto interiors with my next Parts Express order and applying it to the inside of the cabinet lid of my Sony. Before you do any such thing, I'd run it for a while and make sure that the player does not have any heating "issues" (my first and second gen Panasonic DVD's ran pretty darn hot - *knock on wood* for good luck, my A110 still runs though, at least partially because I've been religious about not stacking anything on it during operation that would let heat build up in the case).

On the switchmode power supply, I've never seen a linear power supply on any US export model of any brand - sometimes they're found on the "Japan only" players towards the top of the line, so I wouldn't hold that against the player in any way (not a bad idea to try a linear regulated power supply, just mean that it's not like the Pioneer was unduly "cheaped out"). I didn't see any ferrite clamps on the AC mains in (could be under a board or outside the view on the pic) so I'd definitely see about fitting something there. Parts Express stocks 'em as does Radio Shack - but PE is cheaper by a factor of 3 (once you order enough other stuff to make up for the S&H charge). There are a couple of tiny ferrite beads in the PS circuitry though - but I've found that with the filthy US AC mains in there's no such thing as too much RFI filtering....

Good luck on your tweaks! If it's not too much bother, I'd love to hear about how they're going for you!
All the best,
Morse
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Old 7th December 2003, 04:42 PM   #114
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Default See definition 1

Main Entry: damp·en
Pronunciation: 'dam-p&n
Function: verb
Inflected Form(s): damp·ened; damp·en·ing /'damp-ni[ng], 'dam-p&-/
Date: 1547

1 : to check or diminish the activity or vigor of : DEADEN <the heat dampened our spirits>
2 : to make damp <the shower barely dampened the ground>
3 : DAMP 1c
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Old 7th December 2003, 04:51 PM   #115
Lyra is offline Lyra  Norway
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Quote:
Originally posted by Morse
Hi Christer;

>>>.Hi Lyra

Sorry for going OT occasionally; as someone who's been outsourced and has had to retool his own job skills (an ongoing process at the moment), it's a topic that resonates.

Back on topic, have you tried any tweaks on your ailing Mustek? Or, have you tried to discern the cause for those alarming voltage levels you quoted? I for one would be a bit leery about using any piece of obviously malfunctioning equipment (in which dangerously high levels of AC are sometimes present) unless I thoroughly understood the causation.

All the best,
Morse
Hi...I was not as serious as it might look at first glance
I think the alarming output voltages is coming from some kind of fault in the switched powersupply. I can definitely!!! feel it in my fingertips when touching the output, and GND at the same time. I have had a (quick) look inside, but there was no obviosly (burned out) defects.
To me...an old electonics-engineer (who have forgotten a lot I realize when i read some of theese posts), a switched power supply is not good at all used inside equipent made for hifi/ audio. To me this is WRONG !
Switched powersupply and audio equipment = NOGO (in my ears anyway).........

All the best!
P
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Old 7th December 2003, 05:12 PM   #116
Morse is offline Morse  United States
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Hi Lyra;

Glad I didn't offend! I tend to get a little preachy on the whole "we shouldn't lose our capacity to produce real wealth and become dependant on the labour of others" thing....others can and do disagree.

>>>...a switched power supply is not good at all used inside equipent made for hifi/ audio. To me this is WRONG !...<<<

Frankly SMPS can be a real pain to work with - my first thought is that some component has gone a trifle out of spec - since it's not just the primary, but secondary component values that count there (i.e. a capacitor's equivalent series resistance, a resistor's lead reactance, etc). I'm no expert on SMPS by a long shot though, and debugging 'em goes over my head. I read up on 'em enough to find out that it was going to take a while for me to experiment around enough to come up with one for a portable valve amp project I've got on the back burner. WAY on the back burner - some very qualified people (thanks Dhaen! ) were helpful in putting it into perspective....

Good luck and all the best,
Morse
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Old 7th December 2003, 07:01 PM   #117
Morse is offline Morse  United States
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Default oops....

Hi Lyra;

Almost forgot. Where I was going with that was, if you think the SMPS is problematic, why not convert the unit to battery power from a deep draw gel cell (and of course a charger to be run when you're not playing the unit), or build a linear regulated supply? As an EE, it should be a snap for you. Particularly in the case of battery power, you can expect some significant improvements in sound and picture quality as the RFI on the power lines will be nothing but a memory.

All the best,
Morse
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Old 7th December 2003, 07:25 PM   #118
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Default Re: See definition 1

Quote:
Originally posted by jean-paul
Wasn't "dampening" making something wet ? I learnt that in case of vibrations you can spend time "damping" the vibrations....

Quote:
Originally posted by net-david
Main Entry: damp·en
Pronunciation: 'dam-p&n
Function: verb
Inflected Form(s): damp·ened; damp·en·ing /'damp-ni[ng], 'dam-p&-/
Date: 1547

1 : to check or diminish the activity or vigor of : DEADEN <the heat dampened our spirits>
2 : to make damp <the shower barely dampened the ground>
3 : DAMP 1c


Quote:
Originally posted by Lyra
Switched powersupply and audio equipment = NOGO (in my ears anyway).........

All the best!
P
what harm can a smps do in a mostly digital device with just small output analog buffer?

Again, I would be surprised if anyone can hear the difference.
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Old 7th December 2003, 07:47 PM   #119
Morse is offline Morse  United States
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Hi Millwood;

>>>...what harm can a smps do in a mostly digital device with just small output analog buffer?...<<<

RF hash from the switching. It depends on how good the SMPS design is and how good the V+/V- rail filtering is. There's also the issue with SMPS dumping pulses of RF grunge into the AC mains that can pollute the incoming power of other components. That's why even cheapie CD/DVD players have an "X" cap at bare minimum (if they didn't they wouldn't meet Part 15 FCC criteria) - but it only acts as a 6dB/octave reduction in both incoming and outgoing RFI; the addition of a ferrite choke will add yet more filtering.

>>>...Again, I would be surprised if anyone can hear the difference...<<<

As always in audio that's debatable, but I for one have heard the grunge that switching noise can produce, and have cut it by aggressively using "X" caps, snubber caps, ferrite chokes, and even isolation transformers. Personally the best rectification for sound quality I've ever used is valve type rectification, due to it's soft switching.

If you can't hear switching noise and RF grunge, count yourself lucky - it's one less hassle you have to put up with.

All the best,
Morse
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Old 7th December 2003, 08:54 PM   #120
Lyra is offline Lyra  Norway
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Default Re: oops....

Quote:
Originally posted by Morse
Hi Lyra;

Almost forgot. Where I was going with that was, if you think the SMPS is problematic, why not convert the unit to battery power from a deep draw gel cell (and of course a charger to be run when you're not playing the unit), or build a linear regulated supply? As an EE, it should be a snap for you. Particularly in the case of battery power, you can expect some significant improvements in sound and picture quality as the RFI on the power lines will be nothing but a memory.

All the best,
Morse
Have thought about it but there are to many different voltages, I don't remember exactly but I think +-5V, +-12V, -28V!!! and something with 14-15V on it. Standard computer voltages ++. Just too much job.
BTW I read somwere on the net that the DVD-unit itself was interchangeable with other standard DVD units made for PC's. This would no doubt be an advantage...as the original player is very! little fond of scrathed CD's
I think my other player is a better startingpoint for a decent player....my good old Denon DCD-2560.
Build like a tank, but I havent figured it out yet how to make the outputstage optimal with theese 4 AD-DAC's and oversampling.

Regards...
P
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