One of the most interesting headphones to come out last year was the AKG K371. A rather affordable pair of headphones with a well-tuned sound signature and excellent technical ability for the price. Perhaps following along the lines of Audio-Technica with their ATH-M50x Bluetooth headphones, AKG has decided to launch a Bluetooth version named the AKG K371-BT. This seems like an odd choice for a headphone that is aimed at professionals, but we’ll talk more about that in a bit. In theory, if the K371-BT retains everything that is good about the OG K371 but adds an option for Bluetooth connections, then that would give them a unique position in the market, as long as they do not lose anything from the OG in translation. Starting off with a headphone as good as the K371 as a base, what could possibly go wrong? Well, let’s get into it.
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On first look, the AKG K371-BT retains all of the same design queues and features as the original with a few key differences. So let’s take a look at those now. And please be aware that my opinion on the feature set might not align exactly with yours. We might have different needs or priorities so your conclusion might be different from mine. I’m going to go over each of the features and give my opinions on them.
First up the weight is up 36g over the OG K371. The OG K371 weighed 257g versus the 293g of the K371-BT. That’s not a huge weight increase, it is noticeable but its not a big deal.
The outer part of the headband retains the rubberised coating with a leather-like texture. It feels a tiny bit softer than the OG and the AKG logo that is embossed in the top is less defined.
The headband padding is the same style although it does feel a little deeper and more plush on the AKG K371-BT. That may be because my OG pair of K371 is 6 months old now, but I can’t be too sure.
The headband yokes are the same, still made of metal and have the same folding and adjustment mechanism, for better or for worse. More on that later.
The earcups are largely the same shape however on the BT they have a rougher texture. And also the cups are deeper to accommodate the added electronics.
The earpads seem a little shallower and less plush than on the original. This was immediately noticeable when putting them on the head, there is a lot less room for your ears in these new pads. The result of this is that the long term comfort is also decreased versus the original. And this is my first point of complaint.
AKG seems to have reduced the depth of the earpads on the K371-BT to compensate for the extra depth of the earcups. The result is that the overall footprint of the earcup and earpad assembly is the same as the original despite the extra depth of the cup. I understand why AKG did this but the deep pads of the original were one of the good things that made the K371 stand out from other monitoring headphones on the market. I get why they did it, but I don’t get why they didn’t find an alternative way of dealing with this. It’s just disappointing.
The K371-BT has the same earcup float to help them fit the head snugly. However, they creak. The OG K371 doesn’t creak, why do they creak? And before anyone says that’s not a big deal, I say it is if the noise of that creaking gets transmitted into the earcups and your ears. And yes that’s exactly what happens, move your head, hear the creak. It’s just disappointing.
The disc at the back of the cups is changed slightly versus the original K371. On the original, we had a recessed logo that was lined with a metallic leaf. That is now gone for the AKG K371-BT and the logo is now printed on. The reason for this is that the left disc now houses a touchpad for the Bluetooth controls.
Swipe up to increase volume, down to decrease, forwards or backwards to skips tracks, the usual sort of thing. However, these controls are quite hit and miss and I found myself getting frustrated with them more than anything, to the point that I ended up reaching for my phone more often than not. Honestly, I’d rather they had used physical controls. It’s just disappointing.
On the lefthand earcup, we find the power switch, LED status light and a microphone so that the K371-BT can be used to take phone calls over Bluetooth. All good so far.
In the middle, you might also be pleased to see that the AKG K371-BT has retained a MiniXLR connector so that the K371-BT can be used in a wired mode. Included in the box is a 1.3m straight cable, a 3m straight cable and a coiled cable. Sounds good so far.
Except for some reason AKG has seen fit to use a 4 pin mini XLR this time instead of the 3 pin on the original. Why? There is no mention in any of the specs that this has been wired for balanced connections. All of the included cables have 3.5mm TRS connectors. Can these headphones be used balanced? I don’t know. But what I do know is that my increasingly large collection of AKG mini XLR cables will not work with the K371-BT. So there goes compatibility with the OG K371, the K712 Pro and DT 1990 Pro and a whole host of others. Yeah, you can get a custom cable made for this but finding an aftermarket 4 pin mini XLR cable is more difficult than finding a 3 pin one. And I’m used to being able to swap cables between all of these models, to the point that I even modded my DT 770 Pro to use the same connector. Not a big deal for you? OK, that’s fine but for me, it’s just disappointing.
I really don’t understand this choice at all. But if it is actually balanced then yeah I get it, some people will really like that. Although quite why you would want to run these balanced, I don’t know. And also why on this model and not the original?
Next up on the lefthand cup is the USB connector for charging with the included USB cable. And yes, that’s a Micro USB connector…. In 2020! Micro USB! Where is the USB C connector? Look, I get it, Micro USB is ubiquitous at this point and I’m sure some will argue there is nothing wrong with the Micro USB connector. But if you’re releasing a product at a time when Micro USB is being phased out in favour of USB C. Don’t put a Micro USB in your product! Pretty much every phone released in the past couple of years, apart from Apple, of course, will have a USB C connector. Everything with a USB port on should be using a USB C connector at this point in time.
Is this a deal-breaker? Maybe it won’t be for you and maybe, by itself, it isn’t for me. But I know for a lot of people it will be. This is another misstep and I do not understand this choice either. It’s just disappointing.
We’ve talked about wired connectivity so let’s talk about wireless connectivity. As I mentioned before it does seem like an odd choice to make a headphone designed for professionals with Bluetooth. But on reflection, this could allow the pro to have a single set of headphones to use in all scenarios. Commute to work in the mornings wearing the headphones operating over Bluetooth. Get into the studio and connect with a wired connection. One pair of headphones, multiple roles. Sounds nice, in theory. Actually, it sounds like just the sort of thing I’d like.
The AKG K371-BT operates over Bluetooth 5.0 and they support SBC or AAC codecs. That’s it. No AptX, no LDAC. Ok, I get it, AAC is all that’s needed because it’s supported on the most devices and SBC is supported on everything that supports Bluetooth audio. Also, it’s true that SBC is much better than we give it credit for. However, SBC can be hit and miss and whilst AAC is the best you can get on IOS, AAC performance is often hit and miss on Android. What’s more, Windows 10 doesn’t support AAC over Bluetooth, only SBC and aptX.
Right, I know what you’re thinking; the technical performance and tuning of the device has a far bigger impact on the sound quality than the Bluetooth codec. Absolutely correct! However all other things being equal aptX HD and LDAC are far superior codecs. Whilst none of these other codecs are true lossless, they do give you a greater quality than AAC or SBC. I’m sure that’s fine if you only listen to Spotify or iTunes and for casual portable use its not a big deal, it’s just disappointing.
In terms of Bluetooth performance, I found I was able to watch video on my Windows 10 PC over SBC with no noticeable lag so that’s a good plus point. Is that the first real positive thing I’ve said in this review? Damn we aren’t off to a good start, are we?
There is also no multi-device connectivity. That means the K371-BT cannot be connected via Bluetooth to your PC and your phone at the same time. So if you want to switch from one to the other, you have to disconnect from one and then connect to the other. Not a big deal you say? Ok sure but once you have gotten used to this feature, it’s hard to go back to a device without it. Not a big deal, it’s just disappointing.
Quality Control Issues – The Return
Before we go further I want to address my previous trials and tribulations with the original K371. Many of you might have seen my previous videos or blog article where I documented some build and QC issues with 4 separate K371 units in a row. I think I was incredibly patient with AKG, I’m not sure how many people would go so far as to try 5 different units to find one that didn’t have an issue without giving up. But I did eventually get that 5th unit that was in good condition. At the time I felt that the price, tuning and technical performance of K371 were totally worth going through that effort for. And my efforts drew the attention of AKG/Harman who were able to investigate the issue and make changes to their build and QC process to stop that kind of thing from happening again.
At the time I noted some commentators question my integrity and tried to say I must have damaged them for attention. This is ridiculous, my channel had what? 100 subs at the time? I didn’t really expect anyone to watch my video. I was simply documenting my experience as a consumer. But as time went on, stories started to pop up online where other people experienced similar issues. Particularly in the headband folding and adjustment mechanism (See I said I would talk more about this later). Whilst I still recommend the K371 for its sonic capability and I’m sure AKG have resolved the early run build issues, I still hesitate for that adjustment mechanism.
Yeah, mine is still in one piece and hasn’t loosened off and I know that for a lot of people theirs is fine too. But I really question the long term durability of such a hinge mechanism for something that is meant to be a professional workhorse headphone. I have seen so many comments online saying their hinges are loose, I suspect the issue is quite widespread. It’s just not a good design.
I talked a bit about this in my update video earlier this week. If you want to see how well my original K371 has held up over the past 6 months then check out the video
As I said, I still recommend the K371 for its sonic capability, despite this, I think it is a fantastic headphone. But before we get into the sound section for this K371-BT, let me say this. If you have been paying attention, this review has not been positive so far. And whilst I may have been very patient with the OG K371, my patience has run dry. It’s not easy to write such a negative review, I don’t enjoy trashing something for the sake of it. I genuinely wanted this to be a good product. A K371 with added Bluetooth for portable convenience? Sounds good to me.
I’m sorry to say that I have already arranged a return for this K371-BT. After this review, I will be boxing these up and sending them back for a refund and not just for all of the previously mentioned gripes. But because, and I really cannot believe my luck, they are faulty.
My very first thoughts on listening to the K371-BT were that they are much warmer than the OG K371 but also quite muddy. So immediately this is not the same sound signature as the original K371. I don’t know what the intended sound signature was supposed to be, I would assume the same as the OG K371. However, there is obviously something wrong with this pair of K371-BT. I am hearing a significant channel imbalance. There is a lot more bass energy on the right channel than the left. Also, the left channel sounds a bit more shouty. Totally weird feeling hearing such a difference between left and right.
It’s probably best I show you the measurements. I’ll start off by showing you “unit 5”, my current pair of OG K371. And before anyone says anything, this is using the MiniDSP HEQ compensation which is somewhat based on the Harman target, any headphone that matches the target should show flat on this graph. I know people prefer the HPN curve as it is closer to other ‘normal’ graphs but as this is a Harman tuned headphone, the HEQ compensation makes the most sense in this case.
This is a fresh measurement I took specifically for this video. This serves as a benchmark for the K371-BT but also shows you that my MiniDSP EARS are working. And let me address that point first; the MiniDSP EARS are not industry standard or accurate and cannot be compared with other measurement rigs. It is also possible that the more shallow pads on the K371-BT might affect how well they measure. However, that does not mean that these measurements are completely useless. Especially as they are being used to confirm what is being heard. No one should be looking at these measurements or any others and saying, “This measures like X, therefore, it sounds like X”, that’s not the point. The point is to make sure the unit we are looking at is not broken.
This is very clearly broken.
It’s just so disappointing.
I really don’t know what else to say at this point. After all the issues I had with the OG K371, I’m really not all that motivated to go through all that warranty process again for a mediocre Bluetooth headphone.
Put aside the issues with the sound, let’s assume they sound exactly like the original AKG K371 and they didn’t have this broken channel imbalance.…. Would I be happy with the AKG K371-BT? Sorry to say but my answer is still ‘no’. In terms of their feature set, they are simply quite ‘meh’. Ok sure, none of the gripes I previously mentioned are deal-breakers on their own, but they add up to one big disappointment. If you want a wireless K371 then I would buy the original and a FiiO BTR3. It’ll cost less and have more features. Perhaps none of these gripes are a big deal for you, and assuming that a non-broken unit of K371-BT sounds like the original, then yeah I guess this could work for you. As far as I’m concerned the AKG K371-BT is just disappointing and I’m done.
That’s it, I’ve really nothing else to say. I’ve tried to be as fair as possible during this review, I’m not going to tell you what to do or how to feel about the AKG K371-BT. This is my experience and these are my feelings and with that, I’m out.