[twister6]

New release, great for the NU6 with iPads and iPhones on the go, and a USB C version is coming soon for my Walkman: https://www.ddhifi.com/productinfo/1350761.html

Oh, not just coming soon, already here This little data/power adapter from ddHiFi is brilliant. No need for splitters or usb-c to lightning adapters or camera kits. It's a small adapter with lightning connector going to your iPhone/iPod Touch and then one side with usb-c data output (for your usb dac/amp) and the other side with usb-c power input (for charging).

Here, took a few very quick pictures with iPod Touch. Ironically, I use the latest gen iPod touch for all my "iPhone" testing and its battery is dead, can't hold a charge for more than 4-5min. Now, I can test it for as long as I want to because I'm charging at the same time. Btw, also got their usb-c to usb-c OTG cable (Nyx series, TC09S model). Regardless of what I thought of a short usb-c OTG cable can do, this one gives RU6 a wider soundstage, and I'm still scratching my head because I'm hearing a difference loud and clear. The only secret sauce here is extra isolation of every wire and keeping data and power completely separate. Plus, core of the wire is pure silver while shielding is OFC and SPC.

 

[Sunstealer]

@twister6 is there a quality Android equivalent for dual usb c charging/OTG? A lot of the ones I have looked at have poor reviews saying they don't work.

 

[twister6]

@twister6 is there a quality Android equivalent for dual usb c charging/OTG? A lot of the ones I have looked at have poor reviews saying they don't work.

I talked to ddHiFi and I believe they will be working on usb-c adapter version, similar to the one above with a separate data and charging ports. Otherwise, just go with a usb-c splitter, I have one, talked about it before in this thread, it works, but adds bulk. Plus, many companies that make these splitters use cheaper usb-c connectors. ddHiFi quality is usually better.

For now, your alternative is something like this:

 

[shady1991]

I have a big issue with Cayin RU6's noise floor. I am not talking about the typical hiss, but rather weird almost glitchy noise during very quite parts of very high dynamic range music.
This noise increases every time volume makes that 'glitchy' step(for example from 40 to 41). This means that the signal to noise ratio is worst right above those critical steps, and very best right below it. Now, I could tolerate the best case scenario but at some volumes the SNR is really unacceptable. Of course it is not an issue for most of music out there, which are compressed and brickwalled to oblivion but when listening to well recorded violin concertos for example, it really bothers me. I am 99.99% this is a design issue and not my unit or setup's problem, but anyway, has anybody experienced this?

 

[shady1991]

I have a theory about the volume control, please correct me if there is any information which disproves this.

The resistor volume control has only 8 steps (probably by having 3 resistors with different combinations) and substeps between them change volume only digitally (at the dac level or before). This means that when the volume is for example 30, it is digitally maxed out and at 31 it switches to a lower resistance resistor combination. Now this would increase volume and noise floor a lot, but to compensate for this it decreases volume digitally. Therefore what we get is increased noise by a lot, with barely louder music, hence the damaged SNR. Then moving from 31 to 40 the noise does not change because the volume is increased digitally, and at 40 the dac is using its full potential again.

Anyway, one thing is clear that if we want to maximize quality, we should listen to volumes right below the 'critical' steps. But it is really frustrating that the noise level in this dac is already not great and it does not even use its less than stellar full potential because of imperfect volume control. I wonder why cayin could not implement completely analog volume control, maybe like 6 resistors and 64 steps or smth.

 

[Johnfg465vd]

Btw, also got their usb-c to usb-c OTG cable (Nyx series, TC09S model). Regardless of what I thought of a short usb-c OTG cable can do, this one gives RU6 a wider soundstage, and I'm still scratching my head because I'm hearing a difference loud and clear. The only secret sauce here is extra isolation of every wire and keeping data and power completely separate. Plus, core of the wire is pure silver while shielding is OFC and SPC.

Have you tried OEAudio Cable? mine is onroute and after reading your impressions of TC09S, I'm curious if I made the right purchase.

 

[DBaldock9]

I have a theory about the volume control, please correct me if there is any information which disproves this.

The resistor volume control has only 8 steps (probably by having 3 resistors with different combinations) and substeps between them change volume only digitally (at the dac level or before). This means that when the volume is for example 30, it is digitally maxed out and at 31 it switches to a lower resistance resistor combination. Now this would increase volume and noise floor a lot, but to compensate for this it decreases volume digitally. Therefore what we get is increased noise by a lot, with barely louder music, hence the damaged SNR. Then moving from 31 to 40 the noise does not change because the volume is increased digitally, and at 40 the dac is using its full potential again.

Anyway, one thing is clear that if we want to maximize quality, we should listen to volumes right below the 'critical' steps. But it is really frustrating that the noise level in this dac is already not great and it does not even use its less than stellar full potential because of imperfect volume control. I wonder why cayin could not implement completely analog volume control, maybe like 6 resistors and 64 steps or smth.

If you read the discussions, in earlier posts, about how the Analog Volume control circuit works, you'll see that it does not, in any way, affect the operation of the preceding DAC stage. It's basically just the same as a switched resistor attenuator - that happens to be switched electronically, rather than being a manually turned rotary switch.

 

[twister6]

Have you tried OEAudio Cable? mine is onroute and after reading your impressions of TC09S, I'm curious if I made the right purchase.

I got them all. Love OE Audio as well, and you didn't make a wrong decision. It's a great little cable, has a very compact connector housing, high quality wiring, a bit stiff, but good quality cable. But with ddHiFi and my S22 + RU6 the sound is just more holographic. But you can see from the picture, it has bigger size connectors, two wires side by side, also stiff. In terms of sound quality, OE Audio is between stock and TC09S, and as I reviewer I have no scientific explanation lol!!! Silver material shouldn't influence the sound quality of a cable that carries digital signal. The cable is too short to worry about jitter or anything related to timing. It does have a proper isolation; noise from 5V supply/wires could couple into data, contributing to noise floor which could mess up a few 0 and 1 TC09S definitely has a proper isolation, literally, split into two different shielded wires.

 

[Johnfg465vd]

I got them all. Love OE Audio as well, and you didn't make a wrong decision. It's a great little cable, has a very compact connector housing, high quality wiring, a bit stiff, but good quality cable. But with ddHiFi and my S22 + RU6 the sound is just more holographic. But you can see from the picture, it has bigger size connectors, two wires side by side, also stiff. In terms of sound quality, OE Audio is between stock and TC09S, and as I reviewer I have no scientific explanation lol!!! Silver material shouldn't influence the sound quality of a cable that carries digital signal. The cable is too short to worry about jitter or anything related to timing. It does have a proper isolation; noise from 5V supply/wires could couple into data, contributing to noise floor which could mess up a few 0 and 1 TC09S definitely has a proper isolation, literally, split into two different shielded wires.

Good to know there's some improvement with OEAudio over stock cable. I like the looks of ddHiFi one though, looks more expensive and "audiophily".

 

[Zachik]

I got them all. Love OE Audio as well, and you didn't make a wrong decision. It's a great little cable, has a very compact connector housing, high quality wiring, a bit stiff, but good quality cable. But with ddHiFi and my S22 + RU6 the sound is just more holographic. But you can see from the picture, it has bigger size connectors, two wires side by side, also stiff. In terms of sound quality, OE Audio is between stock and TC09S, and as I reviewer I have no scientific explanation lol!!! Silver material shouldn't influence the sound quality of a cable that carries digital signal. The cable is too short to worry about jitter or anything related to timing. It does have a proper isolation; noise from 5V supply/wires could couple into data, contributing to noise floor which could mess up a few 0 and 1 TC09S definitely has a proper isolation, literally, split into two different shielded wires.

So, the ddHiFi cable that @twister6 loves, or the GUCraftsman braided cable that @Wes S recommends? Choices... choices...

 

[shady1991]

If you read the discussions, in earlier posts, about how the Analog Volume control circuit works, you'll see that it does not, in any way, affect the operation of the preceding DAC stage. It's basically just the same as a switched resistor attenuator - that happens to be switched electronically, rather than being a manually turned rotary switch.

That does not explain increased noise only at every tenth/twelveth step at all. If every step was analog at the same stage of the circuit, SNR would not fluctuate like that.

 

[justanut]

That does not explain increased noise only at every tenth/twelveth step at all. If every step was analog at the same stage of the circuit, SNR would not fluctuate like that.

Do you mean the static that only appears when changing volume or a consistent noise floor?

If it's the latter, I don't experience any with IEMs or Headphones at any volume. Neither when I run it at 85 to my external amp.

 

[Wes S]

So, the ddHiFi cable that @twister6 loves, or the GUCraftsman braided cable that @Wes S recommends? Choices... choices...

I actually ended up preferring the stock Cayin cable in the end.

 

[shady1991]

Do you mean the static that only appears when changing volume or a consistent noise floor?

If it's the latter, I don't experience any with IEMs or Headphones at any volume. Neither when I run it at 85 to my external amp.

It is not static, it is a weird noise during the very quiet sounds (but not during the silence). It can only be noticed during very quiet parts of high dynamic range music. But for the demonstration you can reduce the source volume a lot(almost to 0), then increase cayins volume and check the noise difference between 64 and 65 for example, you will know what I am talking about.

 

[justanut]

It is not static, it is a weird noise during the very quiet sounds (but not during the silence). It can only be noticed during very quiet parts of high dynamic range music. But for the demonstration you can reduce the source volume a lot(almost to 0), then increase cayins volume and check the noise difference between 64 and 65 for example, you will know what I am talking about.

What is your source for the RU6?