Valve DAC? Any point?

[Rosco08]

any comment on the results of adding a Valve based DAC to your systems?

I am almost 100% computer based now ( its just to easy) running from my Mac desktop into airport express out of that using the optical out into my Marantz SR14Ex (i know its an AVR but she is a nice old girl with some big heavy balls, a genuine 140w - does music well i reckon) always to be in source direct driving a pair of mk2 Image 414's. So the signal is getting processed/decoded only in the Marantz that is doing a nice job i think. would a valve DAC do much to the sound as in if it warmed it up would that tend to be a little or a lot? Would this be a cheep way to get abit of the natural warmer airy valve sound and knock of the edge of the very digital set up i have now?

ive been looking at one of these

http://shop.grantfidelity.com/Grant-Fidelity-TubeDAC-11-D-A-Converter.html

Cheep and reviews in the US well but it is a gamble? I dont want to spend a heap as i have mouthes to feed :eek:

any input ?

cheers
Reece :confused:

[got tinnitus]

DAC's are best left powered up 24/7 so in most cases, this means valves are not the way to go.

If you are experiencing digital glare then it's probably due to Airport Express (AE) and the optical connection combined with the DAC in the AVR. I hate to say it but your current set up isn't ideal. AE is really just a "lifestyle" option and not suited to serious music listening.

Can you connect the Mac directly to the amp without AE in the mix? What model Mac is it? Does it have optical output? How far away is the Mac from the amp?

[neil]

I don't know if I agree with that GT. I am using an AE and a valve dac and they sound absolutely excellent. No glare or digital nastiness at all, and a nice rich soundscape. Of course my listening preferences may be different, but the AE is more than just a lifestyle choice that's for sure. I'm sure the Grant FIdelity is fine, but if you can check out the MHDT Havana like I've just bought. We don't sell them as you order direct. A bit more expensive but it is fantastic. I suspect the actual weak point is the dac in the avr... or the avr itself...

[got tinnitus]

Hi Neil

Maybe AE has improved?
I gave it a whirl 2 years ago or so and found it so bitty I could almost count the bits!!

If it's since improved then that's good info to know... But nothing can beat a direct connection!

Reece,
This won't cure your issue (it might help by a couple of %) but try Fidelia in lieu of i-tunes as your playback software.

[omegaspeedy]

I'll tell you what I found when I purchased a very nice CD player a few years back. The valve buffer stage in the Triode Corp CD4SE was untouchable by all the other CD players I trialled. Cyrus, Marantz, Musical Fidelity A5, CEC top loader. The valve gave a density, depth and organic realness that made the other player just look two dimensional and fake.

Now I know I'm talking about CD players here, but It was the valve buffer stage in the DAC that made it work. I would highly recommend a WELL THOUGHT OUT, quality valve DAC.

[Ernie]

A tube buffer stage will help up to mid-level gear, but a valve DAC will ultimately be more useful. The Grant Fidelity would be fine, probably better than the Marantz, but whether it would have the chops as a preamp, who knows.

You'd certainly get the most gain out of a good DAC. Removing the AE from the chain and feeding the signal via USB would also make a difference after you got the DAC.

[Brian Ono]

I tend to agree with Neil .I have disliked the sound for stereo listening from both my AVR s.In saying that the best way to find out is to suck it and see.

[Michael Wong]

Valves in digital are bandaids to tailor the sound.

Sometimes it works, sometimes it doesn't.

[Owen Young]

Hmmm...probably most important is the DAC processor design itself, as the 'tube' part is only the output stage part of such a device, ie. choose the type of DAC you want (NOS, 24/196, Sabre, wolfson...) first. Thereafter, a (good) tube-based output stage can only improve things.

The Grant looks a lot of value for the money.

[Luis]

I believe the Grant Fidelity DAC is a re-branded XiangSheng. I bought one of these off Trademe, new, for $250, and upgraded the 6n3 valve to a $10 Raytheon 5670. Can't see them for sale now on TM, so don't know whether they're still available, but for the low price I think it works very well. I run optical out of the Apple TV2 into it, through the Fatman amp, and the sound is full and realistic.

[Ernie]

Heh heh, another one of those dead horse stories. Albeit a bit more on the oblique side of the Atlantic.

There was a big (really BIG) uproar online (Headfi.org I believe) regarding the rebadging and subsequent markup between XiangSheng and Grant. Yesterdays chip wrapping now and XiangSheng is probably not going to be available any time soon unless some entrepreneurial Chinese person (or otherwise) decides to bring one, or a few in with them.

[Des W]

Yoh,

I have spent some time the last 5 years living in the US--and the bad "vibe" from Grant Fidelity Products/rebadging/etc is a real worry.
Also I heard a selection of their products at a PFeedback Reviewers house and they sounded like crap.
I wouldn't touch the stuff

Caveat Emperor

Des

[Rosco08]

Thanks for the feed back guys....you guys are so fast! work got in the way of shopping today.

To clarify i do really enjoy my system as it sits today. I dont have the space or domestic clearance for a dedicated 2 ch system so the amp stays and it is a very nice sounding old beast (at 26kg moving it out of the house is not happening in a hurry). Its very smooth and dont get me wrong the sound is warm and very easy going.

Yea GT the mac is a 27in imac and it does optical out, USB, Firewire etc
Airport is also output via optical ....but.....
sure one of you guys can help me on this but reading the old manual (sometimes i do) it lists freq response as
Analog Input / Source Direct 8HZ - 80KHZ +/- 3db
Digital Input / 96khz PCM - 8HZ - 45KHZ +/- 3db

Does this mean im better converting to Analog before the signal hits my amp....so external DAC?

[Rosco08]

I'll tell you what I found when I purchased a very nice CD player a few years back. The valve buffer stage in the Triode Corp CD4SE was untouchable by all the other CD players I trialled. Cyrus, Marantz, Musical Fidelity A5, CEC top loader. The valve gave a density, depth and organic realness that made the other player just look two dimensional and fake.

Now I know I'm talking about CD players here, but It was the valve buffer stage in the DAC that made it work. I would highly recommend a WELL THOUGHT OUT, quality valve DAC.

This is what im trying to get! i like the sound now just want more.

Go the Valve DAC i think just which one?

[too_tall]

I have dabbled in valve DAC's, and they are not for me.

I cant put it in words why not, but a valve preamp agrees with me, yet not a valve driven DAC. Weirdness.

Best DAC's I have heard are not based around any particular chipset but a good analog stage. Of course, the valves are in the output stages....

[Ernie]

Does this mean im better converting to Analog before the signal hits my amp....so external DAC?

Yep. Even though there might be DAC chips up the wazoo for decoding multi-channel, they would be living in a noisy electronic environment. A standalone DAC would help your 2 channel experience.

[Rosco08]

Fair point Ernie. There is five or six of them in my Amp plus 5 large torrid amps so no matter what they have done with all the copper shielding it ill still be noisy.
cheers

[Antipodes]

Most often (but not always), valve DACs simply use a valve in cathode follower mode at the output. This will impart a little valve sound, but really it is just flavouring the sound a little, and tube rolling will also only have a small impact.

This is quite different from a valve preamp, where one of the benefits is the absence of the artefacts you get from using solid state to generate gain, and tube rolling will have a bigger impact.

Then again there are some so-called valve preamps that are all solid state except for a cathode follower output, such as the lower level Audio Research preamps of recent times (there is one on TM at the moment).

[Rosco08]

ok so i just took delivery of a Firestone ILTW Asynchronous DAC

Using the USB it supports up to 24/192 using a Tenor TE8802 chip and so far all is good. like i often seem to do i took a punt on this one and was a little concerned as i fired it up for the first time ,,,didnt sound much different to the internal DAC on the marantz maybe a little thinner.....left it running for an hour and presto! hard to explain but a big change already....there is just more music there,,,smooth and detailed at the same time.
ive left it going tonight if the change in an hour of running is anything to go buy tomorrow night should be good fun.

anybody have any ides why the clock source on my mac is greyed out on default..the DAC is showing that it is running in Asynchronous mode but i cant set the clock duties to run out of the DAC,,,,maybe its just doing it by itself?? maybe........

[Ernie]

Yes, the ILTW does the async stuff all by itself. A big improvement on the initial version where you had to open up the case to install a couple of jumpers on the main board.

You're obviously running Mac OS 10.7.

[Rosco08]

Nope version 10.6.8 its on auto up date and that is the latest i can get....
well i think i can now trust that my source is good enough for now the DAc is really nice and seems to match well with the amp....hmmm what next...i have always like the idea of an effortless power amp that has more go than ill ever need....hmmmm that will get me in strife at home