I'll post a PM that I sent to Tom in here, since I'm not sure if it worked (nothing in my sent box, but no error messages when sending). If anyone else has any suggestions...
"Hi Tom,
I felt it was better to send a PM rather than post in one of the threads about DPA (where are they)?
I've just purchased a 2nd hand DPA PDM 1 Series 3, has a glossy case, and the serial number on a sticker on the back. It's handwritten, so most of it has rubbed off. I'll try and decipher it as best as possible and let you know (if you need it). I've upgraded from a DPA Little Bit II (bought brand new).
I've noticed a couple of things and I'm not sure if they're warning signs on issues with the unit. Firstly, the Little Bit sounds detailed, has a large soundstage, midrange is a bit forward, as are vocals. When putting the PDM 1 Series 3 unit in my system, I've noticed several things:
1. Thinner sound, more orientated to the top end. Some stuff with high treble content sounds unbearably bright. Bass is less than the Little Bit II, but I suspect that that's because it's actually tighter and better controlled. Midrange is recessed, as are the vocals, when compared to the Little Bit II. Some vocals have some slight sibilance as well, which I've never noticed with the Little Bit II unit on ANY recordings that I've played during the long period that I've owned it.
2. The PDM 1 Series 3 unit has more details, and a wider/higher/deeper soundstage. I'm hearing a lot more things than I've ever heard before!
3. Drums sound inferior on the PDM 1 Series 3 unit, they lack the 'slam' that the Little Bit II has.
4. There is a slight crackle when the units are powered on via the rocker switches on the back. Not really an issue as I usually leave them turned on.
5. If the DACs are on, turning the tone controls on and off on my preamp (Audiolab 8000C) introduces a nasty spike through the speakers. This has never been noticed by me before, I don't really use the tone controls to be honest. I was only playing around with it because the PDM 1 Series 3's sound was a bit bass light compared to the Little Bit II.
6. In what I consider very odd, the PDM 1 Series 3 DAC has less rhythm/pace than the Little Bit II, but is still very musical. It just seems a bit slower than the Little Bit II. My foot taps quite happily
7. I've noticed on several recordings that I know well, that vocals seem to lack emotion, when compared to the Little Bit II.
Said lady of the house (with very keen hearing) described the sound as thinner and brighter and lacking in bass. She prefers the Little Bit II. I'm wondering a couple of things...
Note: unit sounds better via headphones (Sennheiser HD420 Gold References), some of the issues like midrange/vocals/sibilance disappeared on the same recordings that had issues.
a) Could the AC mains in Australia have anything to do with it? We use 240v 50hz, I know the UK uses 240v, but I'm not sure on the hertz rating. Is this different, and if so, could this create issues. If so, is it easy to fix? I have no technical knowledge/electronics and in all honesty, wouldn't pick it up.
b) The crackling noise when turning the DAC on, or with the tone control on the preamp - is that a sign of possible issues to come? I notice no hiss or crackling from the speakers whilst playing.
c) Interconnects - I'm using the coax cable that came with the Little Bit II to connect to the transport, so I presume that that's OK. I'm using some el cheapo silver plated interconnects to the pre amp, I've never noticed any brightness or issues with them before, could the DPA PDM 1 Series 3 DAC have issues with the brightness of silver interconnects? I have a spare DNM Reson interconnect that I can use if need be. If I remember, DAC 7 DACs were considered to be a bit brighter sounding than the SA7350 chipsets...
d) CD transport - In lieu of my Teac Esoteric P-500 unit malfunctioning, I've been using a Pioneer DV-344 DVD player as the transport (loaned kindly to me by a mate, otherwise I'd have no CD source at all). Could a cheapish DVD player like this not be good enough for the PDM 1 Series 3? Was never any issue with the Little Bit II, so I'd find it odd...
e) Do you have any circuit diagrams/user guides that you could email me/send me? I'm only happy to pay for costs involved etc (would be by Paypal as I don't have a credit card).
f) Upgrades/deltran - what are your thoughts on this? I wouldn't be able to afford any upgrades to the PDM 1 Series 3 (if that's possible) for several months. Also, is deltran'ing a unit really worth it? Does it really make that much of a difference? Are parts still available, and is it that hard to do? To send it to the UK would be dangerous (possibly damaging the transport en route) and costly. I believe Chevin Audio can help here, first I'd have to get the Teac fixed (it's been unused for 4 years, probably a dead laser). I guess, if I could get the deltran parts/instructions, I could get a local electrical engineer to do it for me, in lieu of my skills in the area. That would save a fair bit of money of course in shipping costs.
I paid quite a fair bit of money for the PDM 1 Series 3, and I'd be saddened to have bought a lemon with issues etc. Yes, I know buying units 2nd hand, across the Internet is frought with danger, caveat emptor etc. DPA units seem to be very hard to find, and fetch good prices (I paid 400 pounds 2nd hand for my unit from EBay UK).
Sorry for the long PM, any advice or help would be really appreciated.
Cheers,
Dave
PS I'm keeping the Little Bit II!!! Any advice on leaving it unpowered for long periods? My logic tells me to plug it into power every month or so to have an electrical current running through the unit. "