-
Feeling lucky? Check out the AK 24th Anniversary Giveaway thread and join in the fun!
Is there any point in keeping "Vintage DACs"?????
- Thread starter Wolverine
- Start date
bimasta
Addicted Member
"Flagship" may be a keyword. My best spinner is a Panasonic DVD-A7 — it was the first player to launch the then-new DVD-Audio format, with much higher sampling rates and multi-channel. It was going to compete with SACD, another new format. I figured that Panasonic, with so much money riding on it, would be sure their first one was as good as it could be, transport included.
Listening tests — against CD and DVD players from Sony, Marantz, Pioneer, Toshiba, Samsung, Cal Audio Labs — confirmed it. Dramatically better.
I'll say again, at risk of being boring, that a digital cable will make a great difference too. Blue Jeans Cable sells one for about 20 bucks I think. The construction is different, and it will beat a very expensive normal interconnect, at low cost. I had doubts, but trying it proved it.
When I got my GDA700, and added it to my Marantz CDP with a good IC, the Music was clearly better. I was delighted. I started researching, and learned a real digital cable is different. So I tried one; it was another quantum leap. Together, they're a revelation. I thought the Marantz was great — now it sounds thin and uninvolving. I enjoy Digital now more than Vinyl, except for my very best pressings
Exactly. And the 700 is a very good design, from the power supply at one end to output stage at the other. Many new DACs (affordable ones) use wall-warts — I doubt they can compete in that area, and a Class A output by Nelson Pass will be hard to beat.
OP already owns it, and 2 transports to try. So he's spending no money. Add $20 for the correct cable, and I think he'll be amazed.
northpaw
Super Member
Just to be sure I am understanding what you are saying, by a "digital cable", you are meaning one that is labeled/speced digital (commonly video), with a 75Ω impedance, and appropriately shielded of course (be that double or quad), or, are you meaning something more/other than that? For example, in the former I would include inexpensive RCA-terminated cables from the likes of Monoprice, based on RG59 or RG6 coax, or as I have done in some cases, added RCA (male)-to-F (female) connectors onto the ends of RG59 or RG6 cable.
Funny that I acquired an Adcom GDA-700 at the same time as you (3 years ago this month) and I also have been very happy with it. I paid about 12x what you did, and consider it one of the better buys I've had. Over this period, I have fed it with a variety of CD and DVD player units via coax (always a 75Ω cable) or optical. I never have actively tried to determine if these source units, as transports, sound different through the GDA-700, but whatever differences exist, I can't recall noticing any differences when I have switched transports. I know from your prior posts that I have read that you speak plainly and truthfully, so I will give a closer listen the next time I switch things up. It is also quite possible that I am not as discerning a listener in the areas that these things differ.
bimasta
Addicted Member
If you've already tried an optical cable, it meets the digital transmission standards, and a coax like I've described might not make a difference. There is a Coax vs Toslink debate — I have no opinion on that, as I've never tried Toslink — I only know my Dig Cable beats any normal interconnect.
I don't mean "labelled digital" — many things are labelled digital that are not. But yes, 75ohm. The more shielding the better. AND the shielding should be soldered to the RCA plug all the way around: 360°. Even "high end" ICs only solder the shield to a tab (one point) on the RCA plug, because it's not critical at analog frequencies.
That's how I made mine anyway, after researching online (which dispelled many myths) and as I've said already it was much better than an IC.
As for the transport — I had half a dozen I could try. You only have 2, as I understand it. Mine were all from thrift shops, as I was looking for one that sounded good as a CDP. They were all "good" ones; people were moving to Blu-Ray and dumping their old machines even though they were "top models". When I got the GDA-700 and needed a transport-only, I thought they'd all sound the same, because people say they do. So I was surprised by the gap in SQ — two were standouts, the rest were thin and insubstantial in comparison.
So next time you're in the mood and have the time, try your transports again, with a good digital connection (optical or coax). When you do, drop me a line about your findings...
Last edited:
northpaw
Super Member
Thanks for that information. I know from unscrewing the external collar on the cable side of some RCA fittings that yes, there is a tab and the shield on the cable is cut back such that it does not cover the last cm or so of the central conductor. On the other hand, for ones that have screw-on metal external collars, that region is overlapped by the metal collar extending down the cable for a few cm, and is in electrical continuity with the shield and the outside collar of the RCA connector itself, which it screws into. I doubt that type overlapping geometry forms as effective a shield as the way you described the ones you constructed; I wouldn't be surprised if it is less effective, especially at very high freq/short wavelengths.
In the case of using a properly made coax cable with the standard F terminations, and adding the RCA-to-F adapters, 360° coverage should be obtained due to the way that the cable shield is meshed to the F connector. At least that is what I remember from making up some custom-length cables when I wired the inside of my house for cable TV, 30 or so years ago.
On the GDA-700, I will pay attention to any differences I hear the next time I switch sources around, and I will let you know.
In the case of using a properly made coax cable with the standard F terminations, and adding the RCA-to-F adapters, 360° coverage should be obtained due to the way that the cable shield is meshed to the F connector. At least that is what I remember from making up some custom-length cables when I wired the inside of my house for cable TV, 30 or so years ago.
On the GDA-700, I will pay attention to any differences I hear the next time I switch sources around, and I will let you know.
I just ordered a Audioquest with the following description that I wonder checks the right boxes for a digital cable;
Features & details
Features & details
- Solid conductors eliminate strand–interaction distortion and reduce jitter
- As the surface is made of high–purity silver, the performance is very close to that of a solid silver cable, but priced much closer to solid copper cable
- Hard–Cell Foam insulation is used exclusively in most of AudioQuest’s video and digital audio cables
- Shielding always plays an important role in any cable design, but the shield on coax interconnect plays an especially important role because it functions not only as a shield but a return path as well
- 100% shield coverage is easy. Preventing captured RF Interference from modulating the equipment’s ground reference requires AQ’s Noise–Dissipation System
Looks like it checks all the boxes , I assume it is a digital coax specific at 75ohms , if so then you should be good . Ultimately it’s going to come down to how you think it sounds as I have found that there are different sonic signatures from cable to cable .
Audiofreak71
northpaw
Super Member
Yeah, it seems that they have sought to address key issues. But as Audiofreak suggests, it would be nice of them to actually give a spec, such as stating it is 75Ω cable. Maybe too obvious?
I took at look at their website concerning their "NDS" (Noise Dissipation System) and it seems they are using outer shields that have some ability to dissipate RF interference without being connected to ground (to avoid polluting it), and using a separate innermost shield for the ground/return. It sounds interesting and all, but beyond my pay grade to evaluate. I did find the proposition interesting that in a standard interconnect cable, the ground and the shield [Edit: and the signal return] are the same, and if the shield is picking up interference then the ground could be affected by it. But like I said, sorting it out is above my pay grade.
I took at look at their website concerning their "NDS" (Noise Dissipation System) and it seems they are using outer shields that have some ability to dissipate RF interference without being connected to ground (to avoid polluting it), and using a separate innermost shield for the ground/return. It sounds interesting and all, but beyond my pay grade to evaluate. I did find the proposition interesting that in a standard interconnect cable, the ground and the shield [Edit: and the signal return] are the same, and if the shield is picking up interference then the ground could be affected by it. But like I said, sorting it out is above my pay grade.
Last edited:
bimasta
Addicted Member
I wrote about my DIY cable days ago (#56)" "it wasn't even "magic wire", just lying-around-the-house copper — but it was quad-shielded with foil and 3 layers of tightly-woven braid — and what a difference!"
It's a solid conductor, which AQ praises — and my secret is out. It was just standard Cable TV Cable — and Cable is digital, optimized for Internet*. It's NOT "audiophile" solid-core copper, not 5-Nines pure, only 0.99%, as far as I know. I don't know if it matters. I have "better" wire, OFC, Teflon-foam inner insulation etc, that I was going to replace it with — but now I don't know: it's stranded, and AQ says it induces jitter and distortion. It's also not Silver, and maybe Silver does have a "real" advantage in digital, as it's a bit faster — I had a Meridian DAC ages ago, and its cable was pure silver (not plated).
Also, I don't know either about Northpaw's question regarding the shield — does Digital Transmission Cable even have a "signal return path"? If it's not AC, is it needed? Is it "one-way"? Does anyone know?
* There's a new "cable war" over USB. If some really are better over an 8-ft length, that extra data must be making it through the miles of "standard" cable before it even reaches my USB port. Eight feet of "better" USB wire can't "re-create" data that was lost.
Bumping this old thread to thank those who recommended that I hang on to my “vintage” DACs. I had heard for years that a stand alone CD transport coupled with a DAC could raise the SQ of your average CD playback but for whatever reason never gave it a try. That changed yesterday when I got my first dedicated CD transport (Audiolab 6000CDT) and paired it with the Adcom GDA 700. Wow!
I was not expecting the level of performance I have been hearing. If you have only been using your DAC with your music streamer I highly encourage pairing up a dedicated CD transport. There are several like this Audiolab that are pretty budget friendly and sound great.
I was not expecting the level of performance I have been hearing. If you have only been using your DAC with your music streamer I highly encourage pairing up a dedicated CD transport. There are several like this Audiolab that are pretty budget friendly and sound great.
Last edited:
If they sound good to you yes. Otherwise you can buy something new until something new and better comes out then you can buy that too. See where I'm going with this?