[m8o]

I'm thinking of buying a Audio Alchemy DDE v3.0 with HDCD. They're like 10 years old now. Are they any good by today's standards? Most notably, in comparison to something such as the Mhdt Labs Paradisea or other tube DACs sold at Pacific Valve? I know there's no 'oversampling' or 'upsampling' ; HDCD decoding notwithstanding.

I'd love to hear your thoughts.

Another related question ... If I have a -lot- of tube Gear in every system -- LD II+ for headphones, LD III+ for headphones or floating pre-amd, or amp driving Klipsch's, Butler 5-ch in the HT system , Classic 150 in the hi-end 2-ch system --should I even consider a Tube DAC? Will the sound be "too soft" with a tube DAC driving a DHT tube pre-amp , driving tube amps (either headphone or steroe)???

Again, appreciate the informed replies about this I know I can receive on this great board.
Thanx,
m8o

 

[clarke68]

Quote:

Originally Posted by m8o I'm thinking of buying a Audio Alchemy DDE v3.0 with HDCD. They're like 10 years old now. Are they any good by today's standards?

Are they any good? Definitely. By today's standards? Probably not.

I have a DDE v1.1 that I run at work that I like a lot. Something you might consider if you're looking for a budget DAC is one of the Entech units currently on eBay. They're designed by the same guy (Peter Madnick) but are one generation newer than the AA gear. Since Entech never built up the brand awareness that Alchemy did, their stuff goes for a song.

I personally think that a DAC output stage is a terrible place for tubes, but I know there are others who feel differently.

 

[machead]

If HDCD decoding is important to you, you're pretty much limited to the "oldie but goodie" DACs. I don't know why HDCD is so unpopular with today's designers but it could be due to 1) the relatively high cost of the PMS100 digital filter chip that is a necessary part of any HDCD-capable DAC, and/or 2) the possible problem that a PMS100 has with decoding an upsampled data stream. MSB claims that it doesn't work, while my Muse seems quite happy. Go figure.

Does anyone know of a current generation stand-alone DAC with HDCD?

 

[Pacific Microsonics]

It's fine by todays standards, if you look at the price you can fetch it for. Look at what is out there right now for 500 and what you get with "vintage" dacs and you'd be hard pressed to get a better value. The AD1862/PMD100 combo with a nice output stage isn't easily "outdated" by a lot of the things out there today. Just my two cents.

I also suggesting looking for a PCM1704 or PCM63 dac with PMD100 combo. Makes good music.

 

[linuxworks]

can I ask a repair question about the 3.0?

I have 2 'broken' dde 3.0 dacs. I think its a common fault? on one of them (perhaps both) the op275 chip seems to run hot. I unsoldered it and installed a socket for both o them, then threw in some 5532 chips (the only thing I had handy) and sound did come out of the L/R outputs again.

is this dac worth fixing further? it seems the digital sections all work and there is some overheating problem but I'm not sure what the root cause is (yet).

do people really 'care' about the HDCD chip these days?

 

[FallenAngel]

Are older DACs good : Yes
By today's standards : Obviously they mostly don't handle 24/96, but if you listen to 16/44.1 (normal CDs, not SACD / DVD-A), then YES

Will an older DAC which sells for $250 wipe the floor with today's $750 DACs : ABSOLUTELY!

 

[linuxworks]

are you saying a working dde 3.0 is worth $250ish?

true that its not 24/96. I think it can do 20bit but not 24 and definitely limited to 48k. I don't think there WAS 96k back then (1997?) was there?

I've been reading about the i2s input and that its not philips standard but 'japan standard' or even just AA-private (old inverted strange protocol). I was curious if I could take i2s from a modern pcm series chip (like the AMB gamma1 does) and pipe it into an old dde3.0 dac. but all I've read so far says it wont work and that you'd need that old DTI box to send a compatible i2s stream to it.

I just looked at my other dde3.0 broken unit. this one was in MUCH worse shape - it had those same 2 opamps 'heavily worked on' with diodes under the board, caps removed and moved and some traces have been 'hit hard' ;(

what a weird design. I seriously wonder why this ever was thought of as high end. I've heard endless stories about 'burned out' dde3.0 boxes. does NOT sound like it was properly designed (sigh). its also a 4 layer board (I think) so its really hard to do things to.

maybe my 2nd one is worth the parts (it has the atmel cpu in it, too) and the first one that seems to work is worth it as a mostly-working dac

I'm just wondering - since I have a few modern dacs (gamma1 that I just built, plus a modded 'noodle dac' that uses 8416/4397 combo and sounds quite good - if the AA unit is really worth any kind of overhaul or not.

as I recall, a lot of the AA power supplies died, too, over time. so I would have to re-do the power brick so that all my fixin's won't go kablooey WHEN the AA brick decides to call it quits.

 

[Pars]

Well, if you don't want them you can send them to me

 

[linuxworks]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif Well, if you don't want them you can send them to me

whatcha got for trade?

one (the working one) is my friend's so I'd have to find out from him what he wants to do with it.

I plan to take some close-up photos of their current condition and at least have an archive of what this 'diode mod' looks like and what an umodded board (my friend's) looks like.

I've seen the pdf of the schematic but I have not seen a whole of other details about typical repairs done to this.

 

[linuxworks]

also, are the AA 'dac-in-the-box' DACs worth much?

don't they use very similar chips? I have 2 working DITB's that don't sound too bad, actually. they don't seem to burn out parts as much as the 3.0's did

I plan to raise the 5v lines for some of the chips to either 9 or 12 - that's one typical mod. I've already removed the 2ch opamp (275) and socketed it so I can 'roll amps' all I want on those.

if you don't care about hdcd, I wonder if the 3.0 really was all that much better. it sure had a lot more STUFF in there, and voltage regulators coming out the whazoo

maybe having so many power busses was just typical back then?

 

[Pacific Microsonics]

Nothing to do much with the hdcd playback actually, the pmd100 hdcd decoder chip is used sometimes mainly because of its superior digital filter. The dac chips inside the dde3 are also very good, and many times more preferable to "modern" chips.

The rest of the components inside the dac are alright but what the dac really needs is a nice discrete i/v stage. I know cetoole is designing one

I personally wouldn't bother with the s/pdif on this unit. Get yourself any of the dti models for the i2s connection.

 

[cetoole]

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif can I ask a repair question about the 3.0? I have 2 'broken' dde 3.0 dacs. I think its a common fault? on one of them (perhaps both) the op275 chip seems to run hot. I unsoldered it and installed a socket for both o them, then threw in some 5532 chips (the only thing I had handy) and sound did come out of the L/R outputs again. is this dac worth fixing further? it seems the digital sections all work and there is some overheating problem but I'm not sure what the root cause is (yet). do people really 'care' about the HDCD chip these days?

I too have a DDE v3, and parts of it are quite good, and other parts are absolutely horrible, like said output stage. It is also really odd in that sometimes it doesnt power up right, and you get basically no output and heavy distortion. No idea what this is from, but I am going to need to put some serious work into this little dac in the future, because the AD1862 DACs and PMD100 demand some attention. The output stage really just needs to be completely scrapped though, it is the worst piece of $#!][ I have ever seen in a DAC, especially for use with the AD1862. Definitely dont throw out the bad one though, I am sure someone like Pars would be able to make good use out of it, or maybe you can even fix it yourself.

 

[linuxworks]

so, the spdif receiver chip isn't so great, then?

seems to be an 8412. does it just not de-jitter well compared to the modern ones?

the 8416 is supposed to be very good. any way (that you know of) to adapt the 8416 to this? or, better yet, take the i2s out from an 8416 system and send it directly to the dac chip on this board?

perhaps the entire analog chain should be 'ignored' on this board and then take the output from the dac or filter chip and send THAT to a nice clean analog amp stage?

 

[linuxworks]

one of them DOES seem to work after I replaced the 2 hot op275 chips with sockets.

the other was so butchered when I got to it, removing those chips kind of killed some underlying traces. however I do have that 'clean' working one to study and so I might be able to undo those diode/cap mods and restore it to at least demo-able working condition. at the very least it would prove the main chips are ok, which is a good enough place for me to stop (perhaps)

I think I paid $300 or even $350 for it, used, on fleabay many years ago. like my friend's unit, it worked for a few years then stopped. both have been sitting in my 'fix it' bin and just finally came across them recently.

one 'funny' thing about the AA boards that I never saw on any other - it seems the board was soldered and then 'sanded down' (??) since the solder side leads all have flat edges to them. the clearance isn't that tiny to the metal case - but maybe that was just the way they wanted to be sure the cutoffs were short enough? I never saw that done to any other kind of board before.

 

[cetoole]

I would take the 8412 or 8414 over the 8416 actually. I seem to remember seeing some measurements which support this too. The stuff before the 8412 isnt so hot though, and the 8412 is limited in frequencies it can handle. The DIR9001 or WM8804 would probably be the better choice now. As for the analog stage, it should be completely exorcised from the DAC and burned, and replaced with something competent, even if it involves (shudder) modern opamps. I would prefer discrete, but what you use is your choice.