Dear
@Joe Lau,
@MDR30 (and others)
Here is a question for you. Over the years, I have found that Jade can do a good job, in two roles. The first is the 'intended' role as headphone amp. The second is an 'additional' role as gain stage in small speaker systems. It can help in this role also. I first found out this using Sony active speakers (SRS ZX-1) in my home office system. Later, it has been confirmed with a Korea-made sound system - Arche audio D50A amp and FR2 speakers (single driver) plus a Fostex submini sub. The FR2 speakers are remarkably clear and coherent (no cross-over). Yet even with the sub, the sound is a bit bright and sharp. So I insert Jade into the gain chain. It is easy to switch Jade between this "speaker system use" and "headphone use". I just mute the system, unplug the cable from Jade to the system, and plug in the headphone instead. In the speaker system role, Jade is the first gain stage in the chain. The RCA cables from my DAC go to the RCA inputs at the back of Jade. I turn the Jade volume to 50 percent, or more.
The cable from Jade to the speaker system has a big jack plug at the Jade end, going into one of the two front Jade outputs. I only found a mini jack to rca cable, so I use a minijack to big jack adapter at the Jade end. At the speaker system end, the cable goes into the rca inputs sub, which divides it into low frequencies (for the sub itself) and higher frequencies (passed on the the Arche amp). So, Jade works as a first gain stage, with its output taken on by the amp in the sub, and the main speaker amp.
The sound changes, according to the volume setting on Jade, compared to the volume on the pc or dac, and the speaker amp(s).
Generally, more volume to Jade and less to the other gain stages = better (to a point).
In brief terms, Jade "humanizes" the sound. Especially with NOS tubes (I use Telefunken driver and RCA output).
Less of the problems that I associate with solid state amps, digital harshness, flat soundscape, etc. It brings out more of the music, even from poor recordings or misguided protool work.
I play DSD native files, where the volume is set (as well as PCM files, streaming etc).
Generally the better the source, the greater the benefit of including Jade in the sound chain. With DSD (my best digital sound, so far) there is just a set volume (not adjustable in the Dac or in windows), then Jade, and then to the speaker and sub amps).
In both cases, there are three gain stages. First, the DAC or pc, next Jade, and then the speaker and sub amps. The trick is to feed these from Jade rather than directly from the DAC. With DSD the DAC part of the total gain is set, this is not a "active partner" in the gain chain. With PCM it can be adjusted, so there are three active partners - with volume controls you can turn up or down, so that the total fits your ears, system and taste. In both cases, it is a bit like creating the best sauce to a tasty dish. And the best thing: you decide. If you like the DAC better directly into your speaker / sub amps, just disconnect Jade. But give it a try.
Is there a sonic loss, introducing Jade as an extra gain stage, in a small speaker system? Yes. I think so. There is some loss of detail. And the attack is less immediate. Yet it is a workable improvement if your speaker amp is solid state and not up to OTL standards. So even with the Arche D50A amp, which is no slouch with a linear power supply, I like the sound better with Jade included in the chain.
In fact, 80 percent of my use of Jade is in this speaker setup. 20 percent is with headphones.