[TyTB]

Since folks are talking about differential audio, common mode rejection, balanced and single ended it seems pertinent to correct this point.

With the 4.4mm Pentaconn you very definitely can run a single ended cable to a 4.4mm balanced amplifier via an adapter.

In fact, not that there is much point but for the technical discussion, you can wire a cable with a 4.4mm Pentaconn termination to plug into a balanced amplifier but to operate single ended.

An adapter to go from a 3.5mm to 4.4mm so you can use a 3.5mm cable with a balanced 4.4mm amplifier will use the positive signal from the left and right channels and will run the two ground wires from the single ended 3.5mm to the grounding sleeve of the 4.4mm creating a single ended circuit. The negative signal of each channel are left unconnected, there is nothing shorting as is often stated.

That is also in effect generally how a portable amplifier that has balanced architecture and four amplifiers (L and R + and -) but also has a single ended 3.5mm jack works. There isn’t normally a completely separate single ended set up with two specific amplifiers for the single ended output, it is fed from the + amplifiers of the L and R channels.

ddhifi and ifi audio make 3.5mm to 4.4mm adapters that do exactly the above. I have both, checked both with a continuity tester and used both perfectly safely and effectively in a couple of different applications.

https://ifi-audio.com/products/headphone-adapter-3-5mm-to-4-4mm/

I'm sorry, I appreciate the attempt at thorough explanation, but this discussion of technical details is starting to go way over my head.

Not to sound reductionist or... well, dumb, but to ask you plainly: So, would the 4.4mm Pentaconn on the Sennheiser HD800s, be a fully balanced system, assuming it's plugged into a Balanced Amp, running off a Balanced DAC? Based on your comment, I THINK the answer is no, but I just want to be sure. You mention that using an adapter to go from 3.5mm to 4.4 would also be single-ended.

So, if I want FULLY BALANCED performance out of my Sennheiser HD800s, I would NEED to mod the cables over to XLR, or just buy some XLR cables, right? Then, and ONLY THEN, would I actually have a balanced system, assuming the DAC and Amp are fully balanced, ya?

 

[BS5711]

I'm sorry, I appreciate the attempt at thorough explanation, but this discussion of technical details is starting to go way over my head.

Not to sound reductionist or... well, dumb, but to ask you plainly: So, would the 4.4mm Pentaconn on the Sennheiser HD800s, be a fully balanced system, assuming it's plugged into a Balanced Amp, running off a Balanced DAC? Based on your comment, I THINK the answer is no, but I just want to be sure. You mention that using an adapter to go from 3.5mm to 4.4 would also be single-ended.

So, if I want FULLY BALANCED performance out of my Sennheiser HD800s, I would NEED to mod the cables over to XLR, or just buy some XLR cables, right? Then, and ONLY THEN, would I actually have a balanced system, assuming the DAC and Amp are fully balanced, ya?

The 4.4mm is a balanced connector just the same as an 4 pin XLR or 2 x 3 pin XLR.

Plugging in a 4.4mm into a fully balanced amp with 4.4mm is exactly the same as using 4 pin XLR into an amplifier with XLR or using an XLR to 4.4mm adapter if the amplifier doesn’t have 4.4mm like the Schiit you mentioned but your cable has 4.4mm.

My comment previously was for technical interest in response to an inaccurate statement about SE to Bal adapters.

 

[Whazzzup]

i wasn't thinking a balanced jack adapter but a 4 pin adapter for an se cable.... but whatever works.

 

[TyTB]

The 4.4mm is a balanced connector just the same as an 4 pin XLR or 2 x 3 pin XLR.

Plugging in a 4.4mm into a fully balanced amp with 4.4mm is exactly the same as using 4 pin XLR into an amplifier with XLR or using an XLR to 4.4mm adapter if the amplifier doesn’t have 4.4mm like the Schiit you mentioned but your cable has 4.4mm.

My comment previously was for technical interest in response to an inaccurate statement about SE to Bal adapters.

I see, thank you!

 

[CelestialArk]

It is usually more a peace of mind thingy in terms of engineering.
Usually with the same implementation balanced can give you better performance, but there are also exceptions.
IMO you don't have to worry about it too much except for the plug compatibility issues.

 

[TheTechQ]

Hello everyone.
.

This is the limit of my understanding, though, so I want to ask you whether a specific amp and headphone pairing would be a fully balanced system or not.

I'm looking at getting the Sennheiser HD800s, and the Schiit Audio Jotunheim 2 Amp, with a DAC card.

https://www.schiit.com/products/jotunheim-1

Does this combination of headphones + dac + amp equal a fully balanced system? I personally see two possible problem-points:

2) Even if the Jotunheim's amp architecture is truly fully balanced, what about the DAC? I have the option to buy a "True Multibit" DAC card, or a ES9028 DAC. I've also been trying to read up on what the heck a Multibit DAC is, and it seems like it's just Schiit's name for a much older, resistor-ladder-based DAC architecture, which has since been developped to compete with modern transistor DAC's, but might just be a case of snake oil? IDK. In any case, would either of these DAC options be balanced, too?

Good day,
I just came across this thread (reading for fun). I happen to have a Jot 2 with the current multibit card.

Either card for the Jot 2 is differential, so you can choose which one you prefer.

Multibit is a modern version of the ladder DAC. It’s a bit less precise from an input to output comparison to sigma delta, but some people prefer the sound. If you have the opportunity to try both side by side I would recommend it. If you are solidly in the specs camp, save your money and get the cheaper option.

The Jot 2 gives you half of the amp if you connect your headphones in a SE configuration. You do get balanced amplification if you connect it with RCA, but you are not protected from common mode interference on the connection between the DAC and amp. If you are in a relatively low radio frequency noise environment this may not be an issue.

I hope some of this information was helpful.

 

[tomb]

I'm sorry, I appreciate the attempt at thorough explanation, but this discussion of technical details is starting to go way over my head.

Not to sound reductionist or... well, dumb, but to ask you plainly: So, would the 4.4mm Pentaconn on the Sennheiser HD800s, be a fully balanced system, assuming it's plugged into a Balanced Amp, running off a Balanced DAC? Based on your comment, I THINK the answer is no, but I just want to be sure. You mention that using an adapter to go from 3.5mm to 4.4 would also be single-ended.

So, if I want FULLY BALANCED performance out of my Sennheiser HD800s, I would NEED to mod the cables over to XLR, or just buy some XLR cables, right? Then, and ONLY THEN, would I actually have a balanced system, assuming the DAC and Amp are fully balanced, ya?

He answered sufficiently that his post was a rebuttal to Whazzzup's claim that an SE to Balanced adapter didn't exist ... they (plural) most certainly do. Perhaps if he had quoted Whazzup's post along with his, it would've been easier to understand the context. I understand the possible reasoning behind that, in that quoting someone directly during a rebuttal is a direct challenge and we all want to be nice and cordial to each other, especially while attempting to explain a very complicated and abused subject.

IMHO, you should first have a more skeptical view on products advertised as "balanced," and attempt to check out the details for yourself concerning 4-wire, fully-differential operation of 2-channel stereo. Yes, my earlier post attempted to show the folly in believing the term "balanced" indicates a true fully-differential circuit (4 separate signals for 2-channel stereo). This folly exists for cables and connectors, too. You can't simply decide, "I want Pentaconn," or "I want XLR," and think that will assure you have fully differential capability - it won't. Hence, the skepticism as a potential customer for fully-differential audio is most important.

I wish I could offer you a better way to guarantee that you will achieve the fully-differential audio string that you desire, by recommending certain types of cables or connectors. Sadly, that isn't possible. The audiophile market is to blame, with companies like Eddy Current and others who offer "Balanced" amps that are NOT fully differential with their internal amplifier circuitry. Cables are even more confusing. Adapters of SE to Balanced have been sold in the past that will short out (blow up!) some fully-differential amplifiers. This means that any cable or connector combination is possible and must be confirmed by the buyer for his/her specific application.

Just as a for instance before posting this message, I looked at Schiit's site about the Jotunheim's DAC option. I couldn't find anything on Schiit that absolutely guaranteed that the ES9028 DAC chip was fully differential. So, I checked Mouser Electronics for the DAC chip's datasheet: https://www.mouser.com/datasheet/2/1082/ES9028PRO_Datasheet_v3_7-3074302.pdf. Even that gets a bit tricky with no background on ES chips (I have none), because they seem to be super-marketing the idea of "8-channels" with the chip. However, on pg. 2 of the 58-page datasheet, they clearly show a "FL, FR, and BL, BR" channels available on the output, hence, four complete signals to offer fully differential audio of 2-channel stereo.

I wish all of this was easier, but "balanced" vs. "fully-differential" is an entirely separate segment of the audiophile industry, with its own unique set of claims and counter-claims of products, what they will do, and how they will do it. It's like learning about frequency response and distortion, how those are spec'd and abused, all over again.

 

[tomb]

Just as a further example, I've sold several products at Beezar Audio that involve conversions between fully-differential and single-ended. The PupDAC uses a TI/Burr-Brown DAC chip that TI/Burr-Brown has manufactured for almost two decades now. The PCM1794 is fully-differential with four, discrete signal channels on the output. However, we use an opamp on the output to couple those fully-differential signals into only two, single-ended stereo channels.

The TIII and T4 headphone amplifier (check the links in my signature) are even more confusing, but for very good reasons. They are fully differential in internal circuitry, but single-ended in input and output. However, the T4 does a flip-flop of wiring, by combining the fully-differential signals in the output transformers to end up single-ended. However, it uses a 4-pin, fully-balanced XLR headphone connection. With tube amplifiers, there is always the possibility of leakage through the output transformers, especially in case of a failure. In fully-differential configuration on the output, this could potentially expose someone to almost 300V at the headphone, which could be quite dangerous. On the other hand, a single-ended output will ground these potential voltage leaks. Keep that in mind whenever you see a tube headphone amplifier that claims "fully-differential" circuitry. Anyway, after combining the signals to single-ended in the output transformers of the T4, we still used a 4-pin XLR headphone jack. The reasoning is that the XLR is superior in every way with grounding, even offering a measurable noise reduction. Plus, it's more robust and allows operation of your top-of-the-line headphone without conversion in a high-end, fully-differential environment.

As mentioned earlier in the thread, there are benefits with fully-differential circuitry even without fully-balanced connections on the inputs/outputs. The reverse is also true, but both of these potentially generate more confusion.