|
|
Post by kcatthedog on Nov 18, 2019 6:42:07 GMT -6
Anybody running one here ?
|
|
|
|
Post by winetree on Nov 18, 2019 16:14:37 GMT -6
I'm using the Pro-Jects Pre Box S2 Digital and was considering Toppings DX7 because of the balanced outputs.
After reading Jim William's comments on the DX7, I'm keeping the Pre Box. Great small DAC with the latest dual chips and specs.
|
|
|
|
Post by kcatthedog on Nov 18, 2019 16:37:17 GMT -6
Got a link to Jim’s comments ? The Topping dx7 pro is I guess an improved version ?
|
|
|
|
Post by winetree on Nov 18, 2019 20:29:41 GMT -6
|
|
|
|
Post by LesC on Nov 18, 2019 21:03:15 GMT -6
|
|
|
|
Post by kcatthedog on Nov 19, 2019 4:17:59 GMT -6
Specs on the mqa are excellent, that is what the pro-ject costs in Canada.
Interesting: thx!
|
|
|
|
Post by kcatthedog on Nov 19, 2019 4:51:05 GMT -6
I see our thread mate here monkey ditched his pro-ject for the dx7s , then Jim got one too and modded put the burr browns for analog devices parts: interesting.
The topping pro is above the S.
|
|
|
|
Post by kcatthedog on Nov 19, 2019 6:38:39 GMT -6
A detailed and informative review, just have to listen carefully, due to accent:)
|
|
|
|
Post by Guitar on Nov 19, 2019 8:25:32 GMT -6
Yes I use a Topping DX7S. Not the pro version. I'd love to be able to upgrade to the Pro.
It's my word vs. Jim Williams word LOL.
I hate the one he likes, and he hates the one I like.
|
|
|
|
Post by kcatthedog on Nov 19, 2019 8:39:52 GMT -6
sonic beauty is like all beauty but in the ear of the beholder! All this gear is excellent pick your poison!
|
|
|
|
Post by kcatthedog on Nov 19, 2019 8:43:59 GMT -6
A dilemma for me is the pro ject is around $500, the dx7 pro $900, but this is sort of halfway to an symphony mkii 2x6se mastering module which is ad/da: decisions decisions!  |
|
|
|
Post by Guitar on Nov 19, 2019 8:49:58 GMT -6
sonic beauty is like all beauty but in the ear of the beholder! All this gear is excellent pick your poison! That's exactly right, thank you. The DX7s is more midrange focused, a little thicker sounding, slightly subdued top end compared to many converters. Kicks in the lows enough for me. To me it sounds more 'analog'. I wonder how much of this sound signature is related to the Burr Brown audio op amps. Which have always sounded a little darker to me when compared to other op amps. Pro Ject Pre Box Digital S2 I hear as being very shiny and open on the top, very spacious, lots of front to back depth, almost holographic. But to me it lacked that solidity, and the low end punch that I crave so much. After a while I found it disorienting to listen to compared to what I'm used to. It was just too different for me. VERY different sound presentation based on some of the same components. Just shows you that the "chip" is not everything, not even close. The Topping DX7 Pro version is interesting to me because I do think the DX7S could be improved upon. Even though I use it happily. |
|
|
|
Post by jcoutu1 on Nov 19, 2019 8:52:24 GMT -6
A dilemma for me is the pro ject is around $500, the dx7 pro $900, but this is sort of halfway to an symphony mkii 2x6se mastering module which is ad/da: decisions decisions! Get a Tascam UH-7000 |
|
|
|
Post by Guitar on Nov 19, 2019 9:01:03 GMT -6
A dilemma for me is the pro ject is around $500, the dx7 pro $900, but this is sort of halfway to an symphony mkii 2x6se mastering module which is ad/da: decisions decisions! Get a Tascam UH-7000 I just did a little shootout of the UH7000 DAC yesterday vs a Focusrite Clarett 4Pre. The Tascam is a little behind in 2019. It sounds good but the Clarett just had a little more detail and "information." I think the Tascam headphone amp might beat the Clarett headphone amp though, the Clarett phone amp is a little zingy, almost harsh. The UH7000 phone amp is more neutral sounding and pleasant. My current use of the UH7000 is as a mic preamp / ADC input. I think they are stunning for that. I have two of them now. Obviously I would use the UH7000 as a DAC/interface if I needed to. I am just comparing them in a critical way here because I just did a shootout. I used the UH7000 as a DAC for quite a while. It was beating the silver Apollo, the Emotiva DC-1, and the Audient iD22. Then I moved to Clarett, and finally moved to the Topping DX7S that I am using currently. I guess I'm not the kind of converter user who settles on something. I love these little boxes. |
|
|
|
Post by kcatthedog on Nov 21, 2019 5:11:07 GMT -6
Hey, a buddy who really knows this stuff sent me an interesting comparison of Topping dx7 s vs Pro.
Read on:
So DX7s is good, and in my test sounded about equal to Apollo X DA. I really couldn’t tell any difference in a level matched test, but sometimes “thought” the low end was a hair more focused on the Topping. The I couldn’t confirm that because it would sound the same again. UA did a good job on their DA.
The Pro however has some upgrades from the DX7s and it unanimously sounds better than the X to me. Not enough that most people should worry about it, but there is a detail, smoothness, and separation I just love to hear. The output level is only 4Vrms, so the Apollo and your Apogee are way hotter, though it shouldn’t matter much in the scheme of things. Plenty of places to get level when you need it.
DX7s uses 2 9038K2M, the 2 channel basic 9038. Two channels summed per side.
Pro uses the full 9038 Pro 8 channel chip. 4 Channels summed per side.
Pro upgrades the crystals to Accusonic Femtosecond clocks, from more vanilla clocks.One for 44.1, one for 48 and one for the ESS chip itslef (the DSP). Since the ESS is asynchronous, it ignores incoming clock and jitter and is immune to any source jitter. The internal clock is your clock, and the one on the pro is superb. It’s cleaner than Apollo and surely the Apogee too, though all should have jitter way below audible levels.
DX7 has 3 large filter caps, and two local regulators with heatsinks, and there isn’t a hint of noise.
Pro upgrades that to 4 (overkill) filter caps on the AC, then has ultra low noise regulators, AND THEN uses the ESS 9311 chip which is designed to provide ultimate power to the 9038 chip and simplify design. That means power is double regulated, therfore ultra clean.
DX7s feeds two stages of OPA1612 op-amps (among the best). One converts the current output of the ESS Dac to a voltage output and is the most critical stage in the design. The second is for the low pass filter. They do a great job.
Pro upgrades this to an un-named current to voltage converter. They scratched the name off and won’t tell me what it is. Then that feeds an LM49720 for the filter stage (just as good as the BB and same UA and Apogee use). Th ereason this matters is that is the first chip that the DAC sees at it’s output, and this is the main weakness of the ESS 9038. In mot implementations there is a mid frequency rise in distortion called the “ESS hump”. Whatever they are using for the I-V stge (current to voltage conversion) is correcting this in their design. That’s why they won’t share what it is.
All the Toppings I’ve seen have pretty dirty circuit boards, and seem like they are done by hand. It’s a small problem but I cleaned mine of flux and solder spatter just to be safe. Also, they don’t use thermal tape on their heatsinks. they are just screwed on dry so I put some thermal tape on mine. they really don’t need to be there but they do help the chips keep stable, at the maybe the cost of a little warmup period.
Other than that the DACs feel very high end, and the design ooks amazing to me. 9038 can run in current or voltage output mode, but ESS says current mode it the best. That means that I-V stage is important to get a voltage output, and topping figured out something.
You can select filters on both of them, but I am using linear phase, fast, which is the basic and most transparent.
Of course, guys like dangerous and crane song go a step further and design their own custom filters to tune their hardware to thir liking That’s why they use such strange mixxes of parts and get stellar sound despit not showing big numbers on spec sheets. Crane Song and Benchmark also upsample everything to 211KHz so that the filters reside outside the audio band, but whether or not that’s necessary is a big discussion and nobody agrees.
I will say this, there is nothing at $500 that I think touches the DX7 Pro. It’s probably a game of 5-10%, but there’s no denying it’s just a joy to listen on.
My next best recommendation would be the ADI-2 DAC. But it’s also double the price. Granted you get all of the DSP RME is famous for, and build quality is like a Mercedes. Still, if you don’t need the DSP the Topping actually specs a little better even.
|
|
|
|
Post by svart on Nov 21, 2019 10:30:10 GMT -6
DX7s uses 2 9038K2M, the 2 channel basic 9038. Two channels summed per side. Pro uses the full 9038 Pro 8 channel chip. 4 Channels summed per side. Pro upgrades the crystals to Accusonic Femtosecond clocks, from more vanilla clocks.One for 44.1, one for 48 and one for the ESS chip itslef (the DSP). Since the ESS is asynchronous, it ignores incoming clock and jitter and is immune to any source jitter. The internal clock is your clock, and the one on the pro is superb. It’s cleaner than Apollo and surely the Apogee too, though all should have jitter way below audible levels. DX7 has 3 large filter caps, and two local regulators with heatsinks, and there isn’t a hint of noise. Pro upgrades that to 4 (overkill) filter caps on the AC, then has ultra low noise regulators, AND THEN uses the ESS 9311 chip which is designed to provide ultimate power to the 9038 chip and simplify design. That means power is double regulated, therfore ultra clean. DX7s feeds two stages of OPA1612 op-amps (among the best). One converts the current output of the ESS Dac to a voltage output and is the most critical stage in the design. The second is for the low pass filter. They do a great job. Pro upgrades this to an un-named current to voltage converter. They scratched the name off and won’t tell me what it is. Then that feeds an LM49720 for the filter stage (just as good as the BB and same UA and Apogee use). Th ereason this matters is that is the first chip that the DAC sees at it’s output, and this is the main weakness of the ESS 9038. In mot implementations there is a mid frequency rise in distortion called the “ESS hump”. Whatever they are using for the I-V stge (current to voltage conversion) is correcting this in their design. That’s why they won’t share what it is. All the Toppings I’ve seen have pretty dirty circuit boards, and seem like they are done by hand. It’s a small problem but I cleaned mine of flux and solder spatter just to be safe. Also, they don’t use thermal tape on their heatsinks. they are just screwed on dry so I put some thermal tape on mine. they really don’t need to be there but they do help the chips keep stable, at the maybe the cost of a little warmup period. Other than that the DACs feel very high end, and the design ooks amazing to me. 9038 can run in current or voltage output mode, but ESS says current mode it the best. That means that I-V stage is important to get a voltage output, and topping figured out something. Paralleling chips reduces average noise floor. It doesn't do much for signal quality besides creating some small intermodulation and burning power. It's mostly for SNR specsmanship. The TI ultralow regulators are the ones that I used in my AD/DA box. At the time they were the lowest noise LDO available in the currents I needed. I wonder where they got the idea.. Double regulated doesn't mean ultra clean. It means that it's just double regulated, which also means that if believe you have to do double regulation, your decoupling/layout is poor. Regulators have bandwidths like any other amplifier, because they technically are amplifiers, but with really slow slew rates so that they don't oscillate. Regulators are not designed to "reduce noise", that's what decoupling and filtering is for, and better suited to do. A "low noise" regulator means that it's not contributing much to the noise figure of the output, not that it's actively reducing noise. Overly relying on regulators to snuff noise just makes them burn more power and waste slew rate. More decoupling and better layout makes a larger difference overall. I/V stage IS probably one of the most important pieces, but not for why most people think. I/V conversion is easy. What people think they need are super wide-bandwidth opamps here, but those opamps typically have very poor input current noise, which helps ruin SNR.. They also typically have poor CMRR and PSRR, which is also hampered by the mistaken belief that multiple stages of regulation somehow absolved the designer of needing large and careful decoupling... And then the fast opamps typically need lower feedback resistor values to stay in a lower noise region, but then burn a lot more power doing so. A regular audio opamp would be absolutely fine here as long as the slew rate is fast enough for the bandwidth. My guess is that the I/V part with the scratched off markings are actually a low-bandwidth audio opamp like the NE5532 or something and they scratched off the markings so that folks wouldn't be unhappy to see them in a design they're buying mostly on specs and the expectation of faster=better.. I mean, why wouldn't they scratch off all the parts? Because they want you to see the parts you'd be happy to "upgrade" to, but not the parts that everyone deem inferior (even though they're perfectly fine). Topping just used the common knowledge that I is better output because most V output DACs simply use a shunting resistor to convert I to V. You can still do that, and a lot of DAC purists believe it's better, but more folks believe the active I/V conversion maintains better linearity over frequency. You can also incorporate a stage of LPF into that I/V conversion for free as well and then use the second buffer as the second LPF stage for better alias/image performance. |
|
|
|
Post by Blackdawg on Nov 21, 2019 12:51:12 GMT -6
Has an AES input and Balanced outputs. Very cool. I might have to get one.
|
|
