The Caiman MKII: taking a bigger and better bite

[StanleyB]

Hi Adam,

the function button is there to select a few additional functions.

The I2C bus is there to give access to the DAC chip I2C capabilities. That includes the 16 to 32 bitrates and 128 to 768kHz oversampling rates. The current maximum on other DACs is 384kHz. The Caiman II is capable of twice that. I am leaving it to the coders to come up with suitable software routines that can control the DAC chip via a RPi, or even a PC. A separate I2C adapter board under development will allow for additional functionality, including the use of an I2C LCD display, or a I2C remote control connected to a RPi.

The headphone circuit uses a higher voltage and is aimed at the midrange and above headphones with large drivers. Bass is also deeper and more pronounced due to the higher line voltage of the headphone circuit. So if you like low listening levels, a narrower dynamic range, and weak bass, then the headphone output on the Caiman might not suit you. The higher line voltage also results in a better extension of the treble. I can't say if you would hear a difference with your HD650. It all depends on how good your hearing is. But the deeper bass can cause the HD650 frame to rattle when you have the volume at maximum whilst listening to bass intensive music like reggae. It is OK with the HD800, which has a sturdier build quality.

[Theadmans]

Thanks for all that Stan - very informative - certainly food for thought. I will eagerly await further developments over the Summer (the Caiman II might make a nice Xmas present to myself!!).

[Old George]

Hi Stan,
At the moment (and for the foreseeable future) i'm using AKG 550 headphones, am i likely to find a tangible improvement running the Caiman 2 as opposed to my Bushmaster MK2?

I see the 12 volt battery packs are still usable on the Caiman 2, Will the Caiman draw more from the battery? I have to use a grain of wheat bulb to stop my battery cutting out.

Finally, what price bracket are we looking at for the Caiman 2?

[mkrzych]

When I started thinking about a MKII version of the Caiman DAC, the first thing that I decided upon from the outset was that it would have to be just as ground breaking in terms of price versus performance as the MKI. It is quite easy to fall into the trap of capitalising on the name of a successful predecessor, without any technical justification. But pushing the boundary even further is easier said than done. I often wondered if I had bitten off far more than I could chew.

In order to get an idea of what would make technical and audible differences versus what were just suggestions from couch potato experts, I decided to build a few prototypes and spend some time listening to them. Each build sounded good enough to sell in its own right, but the sound quality difference was in most cases merely a step up. But for the Caiman, I was only interested in improvements that were a substantial leap.


A selection of the prototypes that I designed and built to evaluate the performance and technical complexity of some parts that might be suitable for the final build.
Anyone who knows about the cost of designing and building electronic products would also know that the total cost of those prototypes would have been astronomical. Looking back, I reckon that I got possessed by an obsession for perfection, without keeping an eye on the R&D costs.


Things only got more complicated when some new components came on the market, and when some manufacturers gave me permission to use their parts in a consumer product, or use them in a manner that was not listed in their official datasheets. The ultra low noise regulators from the satellite communication industry made a significant difference especially. So much so, that I decided to try them in a 32 bit D to A configuration and compare that prototype against an otherwise similar 24 bit design and layout. The test results ended up costing me a year delay, partly due to a revised layout change that was optimized for 32 bit D to A number crunching.
Running in tandem to that were my tests on different types of USB audio conversion methods, and the added complication of software drivers. In the end I decided to settle with a 24/96 USB chip operating in adaptive mode that would not require any special drivers when used with different operating systems. Combined with my own async firmware routines, the outcome was actually better sounding than the alternatives I tried. Running the USB chip from the Caiman internal ultra low noise power supply, instead of using the BUS power, made even more of a difference.



The addition of an I2C BUS will allow the Caiman to be expanded even further. But I am not looking that far ahead yet.

My next goal is to get it all up on my website for a June launch.

That's a very good news since Caiman is superb sounding DAC. What DAC chipset you've used Stan and what OPAMP for HPA? What are the chassis dimensions?

[StanleyB]

Hi George, I have no idea if the K550 will sound better to your taste. But I have never heard my K701 sound any better with a more intricate bass and a true spatial analogue sound.
Now if you had a HD800 instead, you would be having a grin from ear to ear. I can see the Caiman MKII becoming a benchmark for HD800 owners. The Caiman headphone performance alone puts the Bushmaster I & 2 to shame.

The current consumption is a bit higher at 70 to 80mA, depending on whether it is a 16 or 24 bit file.

If you put £300 aside, you should be OK. The Caiman is about 30% bigger and heavier, which just about accounts for the extra 30% price increase over the BMII on a cost to weight ratio. I am not adding a premium to the price for the leap in performance.

[mr sneff]

Stan, does the MkII still have the muting relay that 'tweets' between tracks?

[Old George]

Hi George, I have no idea if the K550 will sound better to your taste. But I have never heard my K701 sound any better with a more intricate bass and a true spatial analogue sound.
Now if you had a HD800 instead, you would be having a grin from ear to ear. I can see the Caiman MKII becoming a benchmark for HD800 owners. The Caiman headphone performance alone puts the Bushmaster I & 2 to shame.

The current consumption is a bit higher at 70 to 80mA, depending on whether it is a 16 or 24 bit file.

If you put £300 aside, you should be OK. The Caiman is about 30% bigger and heavier, which just about accounts for the extra 30% price increase over the BMII on a cost to weight ratio. I am not adding a premium to the price for the leap in performance.

Hi Stan, thanks for the prompt response.
Price sounds very fair, i'll start saving.

[StanleyB]

Stan, does the MkII still have the muting relay that 'tweets' between tracks?

It is a completely different design. You'll have to look for a 2nd hand MKI if you miss those tweets .

[mr sneff]

It is a completely different design. You'll have to look for a 2nd hand MKI if you miss those tweets .

[struth]

Me too Stan