[PolkManiac]

I read your review, one of the most strangely written reviews I've ever read...

 

[shigzeo]

It may well be that. I agree.

 

[ExpatinJapan]

I read your review, one of the most strangely written reviews I've ever read...

I love them.

 

[reficul560]

It seems like the Theorem 720 DAC only has a USB input. It doesn't have a line in or optical in, does it?

 

[midnightwalker]

  It seems like the Theorem 720 DAC only has a USB input. It doesn't have a line in or optical in, does it?

 
No

 

[PolkManiac]

Nope, I think the lack of those inputs and the internal components needed to make them work is what allows them to keep the balance of size and battery life

 

[midnightwalker]

This is what I have found during my test between M8 (the model I have is one with RSA balance hp out) and the Theorem.

Using my HD800 with Alo Ref-8 cable, both set at high gain:
To get the same suitable volume level of my listening -- I need to have:

12 or 1 o'clock pot on Theorem
3 o'clock pot on M8
-- And same thing happened when I tried with my other IEMs and cans, seems Theorem has more gain at the same setting to M8. Not sure about other unit, but mine is like that.

Which one do you think better to drive the hd800?

 

[muzic4life]

Both is very good and just a slight different in sound-color (but still neutral to my ears)...i would say theorem has a bit of more fuller in sound..but the clarity will be on M8..with bass swicthed to medium, treble stays minimum...and impedance to highest..i like to use the M8...the sound is very nice..enough bass..and the clarity and layering is very pleasant to listen...

 

[georgelai57]

I find it strange that the Theorem comes with differently shaped USB mini jacks (for input into the unit) yet both work. What gives?

 

[shigzeo]

As long as they interface with the USB pinout, that's all that matters. I've seen a number of differently shaped plugs in my day.

 

[georgelai57]

As long as they interface with the USB pinout, that's all that matters. I've seen a number of differently shaped plugs in my day.

I guess that's true. USB must be pretty hardy since one or the other shape will wiggle.

 

[rpaul]

The Theorem works fine when connected to an iPad Mini, but I keep getting "device not certified" warning and thus a failed connection to the new iPad Air. Is there any way I can get it to work with the Air?
 
I am using the included lightning connector cable, and I have emailed Cypher Labs sales since I didn't find any support contact info on their website.

 

[rpaul]

  The Theorem works fine when connected to an iPad Mini, but I keep getting "device not certified" warning and thus a failed connection to the new iPad Air. Is there any way I can get it to work with the Air?
 
I am using the included lightning connector cable, and I have emailed Cypher Labs sales since I didn't find any support contact info on their website.

 
Nevermind, as David @ Cypher Labs pointed out, I can just use the Lightning USB cable that came with the Air along with the Mini USB adapter supplied with the Theorem - I had forgotten that it was in the box. Actually much more convenient to use it with the longer cable.

 

[shigzeo]

Yeah, I've not found a device that doesn't work with the Theorem. Of course my use of Android is limited to swag devices.

 

[Thraex]

   
Emailed David instead. Below is an excerpt. Super quick replying btw

The DAC section is basically the same as the Solo -dB, both will process 24/192 on computers and some android devices. Apple devices are more limited, but still very high quality with 24/96 on iPad2 and above, 16/48 on other Apple devices. You can also use a FLAC player app on the iOS devices (not Classic). I have a blog on this topic somewhere on the website.
 
The audio quality is in my opinion better than the Solo -dB + any other portable amp. Maybe I should make an analog amp to go with the Solo -dB.

There's a lot of confusion about which bit/freq each attached device supports, sticking with Apple's, Cypherlabs on official specs confirm only 16/48 for iDevices and in the manual just refers to "96.0 on some iPad models" (16 or 24 bit?), here it's reported 24/96 on iPad 2 and above.
Does it just replay the file but will downsample it to 16/48 or it'll remain bit perfect 24/96 till output?
 
Already a lot of USB DACs could be used with iPad and CCK (or the newer variant Lightning to USB Camera Adapter) to output bit-perfect 24/96 and above, but there are a lot of limits: the use of a USB hub or a USB charger, the right app and software, and so on...
So many problems to solve that I've started a thread just to sort them all out: http://www.head-fi.org/t/625493/ipad-with-24-bit-files-high-storage-capacity-portability-bit-perfect-configurations-that-work
 
So, does this Theorem 720 DAC give same 24/96 bit-perfect without the need of a CCK/LtUSBCA or a USB Hub/Charger?
 
Apple seems to limit stuff to 16/48 ragardless and even Centrance HiFi-M8 limits it now at 16/48, "MAYBE" 24/96 in the future.
So till now no confirmation that using Apple officially approved digital out any idevice will output more than 16/48.
Does Cypherlabs is the first one to succeed to have a single device to do all the 24/96 bit-perfect thing?
 
I'm waiting a clear response to move on from my actual proved 24 bit-perfect iPad/USB DAC setup.