[mfst23]

Till today, there are only 3 dap models to choose from which has high power output which are suitable to drive demanding headphones. With the small form factor and high power amp, all the current models playback time are very short and none cannot even reach 20 hours. It may looked like it is a lot but in reality as the battery capacity degrades over time, it becomes a chore having to charge it almost everyday for heavy users.
 
I suggest Ibasso consider making more models which caters to different segment of markets. Ibasso should have at least another model that has the same form factor of DX50 but has lower output power of say 30mW (lower output means more space for battery) and a larger battery to cater to those who prefer a much longer battery life with a minor sacrifice to sound quality. Of course I don't expect Ibasso to make a dap similar to  Cowon X9 which has 110 hours of battery life. Even a small form factor Cowon D20 has 90 hours of run time.
 
The UI of new models should retain the UI of DX50 to reduce frequent firmware update and also to save cost.
Developing new UI is always costly, time consuming and worse still buggy in the initial years.
 
I for sure will buy a new dap from Ibasso with the above features even if the cost  is close to DX50.
 
Thank you.

 

[Solrighal]

Or buy a Fiio E18 and use it to recharge your DAC battery?

 

[ProtegeManiac]

  Till today, there are only 3 dap models to choose from which has high power output which are suitable to drive demanding headphones. With the small form factor and high power amp, all the current models playback time are very short and none cannot even reach 20 hours. It may looked like it is a lot but in reality as the battery capacity degrades over time, it becomes a chore having to charge it almost everyday for heavy users.
 

 
Not just Ibasso, but Fiio is coming out with the X1 was designed with lower power output and for driving IEMs, however, such a design won't mean that much longer battery life, only a smaller form factor similar to an iPod Mini, but basically the people excited for this are those who want something more powerful than a Sansa Clip, but is still relatively cheap at $99 compared to other non-integrated audio chip DAPs.
 
In any case, didn't Ibasso already deal with battery life by using the Samsung S3 battery on the DX50? I'm actually considering getting a a used DX50 instead of the X1 if I find one cheap - I have three spare batteries on my S3 and also a battery charger (like a camera battery charger - you put in a battery instead of hooking up the phone to its USB port), since I can always just put the DX50 in my messenger (laptop) bag and use the phone if I don't have one with me.
 
-----------
 
Now, I know neither addresses your needs for a smaller DAP with longer battery life, but you have to be realistic here. A smaller form factor will likely mean a smaller battery, and you can't compare such DAPs to more mainstream designs like Cowon. Cowon, Apple, Samsung, most Sony, etc all use a single audio chip that has both the DAC, digitally-controlled voume control, and headphone driver chip built into it; by contrast, Ibasso, Fiio, etc use a dedicated DAC, analog output opamps, and an actual power amplifier circuit with capacitors that are closer to the size that you'd find in a dedicated amplifier. Making a 30mW DAP isn't impossible, but given they're already using an amp circuit that will take up that much more space, it makes more sense for them to squeeze out at the very least, around 100mW minimum and get a wider range of IEMs and headphones that can work with it, even if it is a smaller form factor.
 
Think of it this way (in terms of the audio circuits, not their CPUs and responsiveness) : the first group of DAPs/smartphones are more like an ultrabook with a low-voltage Intel i5 running its own integrated GPU, while the second group is a lot more like a gaming laptop with an Intel Core i7 (and some laptops might even use a desktop version) and a GT865M. There will be two problems in designing something between these two however. First, as I've stated above, having a dedicated graphics chip or a dedicated DAC, output op-amp, and amp chip will mean occupying the same amount of space in a chassis (don't factor in something like the GTX760 ITX vs the Titan though), and 30mW isn't that far off the 15mW output of the best integrated chips save for better current. In laptop terms it will be like getting a ULV i7 mated to soemthing like a GT750M, except that kind of laptop actually has a much wider market - people who would want to be able to edit photos and videos, and maybe do some lighter gaming on it. The second problem is that, unlike laptops, there isn't yet an integrated chip that is a lot more like a Trinity (heck even a Llano) APU, on top of which, I'm not sure if in case an audio chip does come out as such, if it can work with some larger caps outside of that chip to help the amp section, or if there's a way to circumvent using that and still provide better current than an integrated chip.
 
Or actually there is a way that a DAPs circuit can be reduced in size, and that is to eliminate the need for an analog output stage and potentiometer (the latter was eliminated in the DX50), and use a circuit similar to the Wadia 151 Power DAC where the DAC chip directly feeds the amp output stage. However, it relies on an upsampling circuit to take the digital signal to 32bits, that way the digital volume control doesn't dip below 16bit. One can argue that you can go as low as 14bit or even 12bit, but the problem is that it is very likely that the type of people who will buy such DAPs will not be happy about that, regardless of whether the actual sound has any audible degradation, while people who don't even know that music is at 16bits (much less that 20bit, 24bit, and 32bit are available) will likely not be swayed into buying a DAP with buttons to occupy a pocket and perform a role that their carrier-subsidized touch screen phone already does.

 

[mfst23]

Thank you for the detailed reply.
 
I fully agree that discrete audio components take a lot more space and has much higher current output. But the sound quality depends very much on the selection of components used and the may not be much better than the single audio chip. I am not suggesting that Ibasso changed their design to this configuration which has limited current output.
 
I am suggesting to Ibasso to take this challenge to redesign the circuits to a more compact scale with lower current ratings and thereby increasing its playtime. The power ratings of most IEMs and earbuds are very small. If the dap playback time is very long, then there is no need to have a removable back battery cover which is not space efficient. The dimensions of this dap can remain the same as DX50 which is perfect. At the moment, there is no product that fits into this category of having high sound quality and long playback time.

 

[ProtegeManiac]

 
I fully agree that discrete audio components take a lot more space and has much higher current output. But the sound quality depends very much on the selection of components used and the may not be much better than the single audio chip. I am not suggesting that Ibasso changed their design to this configuration which has limited current output.

 
No I didn't take it to mean that that was what you meant. I was only saying that inherently dedicated chips and circuits as in these DAPs cannot get much smaller than the X1, and that one already had to give up the larger battery (and digital output, I think), and anything smaller than that is likely going to make huge compromises in other areas, most likely the battery, or in the case of those USB-drive sized players with a "real" Class A/B amp circuit, the screen and controls as well (not only smaller but no more album art, etc, in order to use a very simple single core processor). 
 

 
I am suggesting to Ibasso to take this challenge to redesign the circuits to a more compact scale with lower current ratings and thereby increasing its playtime. The power ratings of most IEMs and earbuds are very small. If the dap playback time is very long, then there is no need to have a removable back battery cover which is not space efficient. The dimensions of this dap can remain the same as DX50 which is perfect. At the moment, there is no product that fits into this category of having high sound quality and long playback time.

 
Actually at the time the DX50 was being developed I said I'd prefer the same thing, but perhaps their own understanding of the market was that they could sell more of a DAP that has a replaceable battery (and one that's relatively easy to find) and works with even the HD600 rather than a 100mW or less DAP designed for IEMs with a sealed case and a larger battery. However, one of the concerns that was driving the need for the replaceable battery (and the larger case as an acceptable trade-off) was the servicing of the battery. Sure, maybe a low output amp circuit paired to a larger battery might have a longer charge and longer usable life, but when it does fail, chances are they'd need to send it back to replace the battery (at minimum, order some kit like iPod batteries that come with a spatula, and the risks of doing that on one's own with no one else to be responsible for paying for damaged parts), and the thing here is that some people are concerned with having to do that. Shipping costs, time, Ibasso's capability to service such units (which can drive up the initial cost), and even Customs* are among hte issues for those who prefer the removable battery. 

 
*Not all countries have shipping and Customs clearing as straightforward as in the USA. Here for example we have a clause of the law that basically says, "Customs Agent can call ******** on everything you claim, paperwork or not," and  we've had people being charged for duties even for units being returned after repair or replacement. In one case they had documentation that a unit was sent back to China, but then smart-arse Customs agent goes, "oh yeah? so then why does this thing here have a different serial number than what was sent back?" and emails from the manufacturer were dismissed. Yes, sometimes that's just their way of saying, "bribe me."

(Let's not do further discussion on this angle because, as much as it's related to Audio, if it goes beyond this post, the mods will bring the hammer down for verboten topics like politics...just don't argue on this point, leave it at that, or we'll both get a slap on the wrist in our PM inbox and the deletion of the posts)

 

[olddude]

If you want long battery life, just buy a Colorfly C3 and get a good-sized amp to go with it that will drive your bigger phones.  I was using the C3 and the BH amp (w/iems) and didn't have to recharge for weeks.  You may need a bigger amp if you are driving phones, but still, the sound of the C3 is just about comparable (albeit different) than the DX50.  
 
To expect iBasso to make a marketing decision based on what you want is probably not gonna happen.  They need to sell units (lots of them) and with smartphones capturing most of the market, the audiophile sector is pretty small.  To slice into their sales by making "in-between" devices is not something they would likely consider.  I'm sure they thought long and hard about the DX90 before going ahead with it, as it would likely cut into the DX100 sales and probably the DX50's as well.  But they could sell it as a "better" version of the DX50 and make up sales that way.  Making a "lesser" audiophile device simply to extend battery life seems like a hard sell.  Why not just buy an iPod instead?  

 

[Jung Woo Cho]

Sorry to disrupt but What's the function of digital filter? Sharp rolloff and slow rolloff?

 

[ProtegeManiac]

Sorry to disrupt but What's the function of digital filter? Sharp rolloff and slow rolloff?

 
On Ibasso DAPs? Better ask in one of the Ibasso threads - there are different kids of filters, not just analog and digital, for different purposes.  You didn't even mention what frequencies are stated and how they're affected. For example you can have a subsonic filter to protect drivers not designed to go that low, and if it has two settings on the slope, if you look at the graph below say 40hz, the sharper one looks closer to a nosedive below that and the other one will look more gradual.

 

[cel4145]

Thank you for the detailed reply.

I fully agree that discrete audio components take a lot more space and has much higher current output. But the sound quality depends very much on the selection of components used and the may not be much better than the single audio chip. I am not suggesting that Ibasso changed their design to this configuration which has limited current output.

I am suggesting to Ibasso to take this challenge to redesign the circuits to a more compact scale with lower current ratings and thereby increasing its playtime. The power ratings of most IEMs and earbuds are very small. If the dap playback time is very long, then there is no need to have a removable back battery cover which is not space efficient. The dimensions of this dap can remain the same as DX50 which is perfect. At the moment, there is no product that fits into this category of having high sound quality and long playback time.

I would be really surprised if the headphone amps and DACs in DAPs could be optimized a lot more for lower power consumption. Maybe a smaller screen and more energy efficient processor for the firmware?

Regardless, we all know how this works. Phones and tablets keep getting faster and thinner from generation to generation, but battery life does not go up substantially. For whatever the reason, the electronics industry thinks that <10 hours (or even only 5 or 6 hours) of usable battery life is what most consumers want/need. At least laptops have gotten better with the Core i3s/i5s and SSDs.

Personally, I'd just be happy if audiophile DAPs would start designing very user-friendly, super feature-rich firmware.

 

[7S Cameron]

Wrong thread.