The announcement of the upcoming Symphony amplifier has resulted in quite a few questions and remarks from some members. Therefore a few answers from my side.
First question of course is “how much”. Well, I haven’t decided yet but most probably prices will be around EUR 1000,- or USD 1500,-. Sorry, admittedly not really cheap, but given the quality of built and parts as well as the rather low number of amps produced such prices are inevitable. Customers who live inside the European Community have to be aware that that they also have to pay an additional 19% VAT.
The amp will be available in two different color schema’s. The black and silver combination as shown in the pictures as well as a silver-grey combination similar to the OPERA. Thus people may choose.
There are some future plans for a SYMPHONY amplifier without DAC (called CONCERTO). However, my recent investments in new models have been very high (almost USD 200,000.-!!!) and I simply first want to see how the acceptance of the new SYMPHONY is. Meanwhile the CANTATE will stay in my programm and is certainly a fine alternative for a very affordable price.
“ Does Corda's balanced setup sound different to single ended setup ?”
In my opinion the answer is “yes”. I remember well the time when the idea for balanced came up for the first time. I then already had a first design of the OPERA finished but made a prototype of an amp that allowed me to switch between three modes of operation; regular passive ground, active ground, and balanced ground. I thought the results to be so convincing that I made a complete redesign of the OPERA.
I’m aware that true balanced operation (at least in theory) offers even some further sonic advantages but balanced ground is much simpler to use (no need for expensive recabling of headphones) and more universal.
“ I wonder why Jan continued to use the LM6171 ops when there are newer ones out?”
Simply because I still prefer the way they sound. I have tried some of these newer audiophile opamps but they haven’t convinced me yet. Sure, the LM6171 is not very easy to use, but with proper implementation it is, in my humble opinion, simply the best sounding opamp of all.
“ The amp's digital rotary encoder will replace the manual relay that used to mute the sound. No more clicking relay noises! “
Sorry, but this seems to be a misunderstanding. The muting relais of the OPERA indeed no longer is needed. However the digital rotary encoder is used for volume control only. And this volume control is very special indeed. Using the encoder switch and 5 relais I was able to implement a quasi-logarithmic discrete volume control that has some major advantages over a regular discrete potentiometer.
The left headphone output still has a 120 Ohm output impedance. However, inside the user can easily place some post shunts to give this output a low output impedance similar to that of the right headphone output. No need to ask for custom changes anymore.
“ Digital end is severely improved and according to Jan, 44.1kHz sounds as good or better than 96kHz-upsampled audio, due to extremely high jitter reduction in the DAC. “
It is true, the DAC does not offer upsampling to 96 kHz or 192 kHz. (but it does offer standard oversampling!). The reasons are two-fold:
- Upsampling does not provide any additional information but basically (only) helps to reduce jitter. However, by lowering the frequency settings of the PLL of the digital receiver of the DAC-section jitter reduction is already clearly better than the standard implementation. This not only is cheaper but it also prevents artefacts introduced by the complex algorithms needed to calculate the new sampling values. The major disadvantage of using non-standard settings for the PLL is the fact that the receiver is no longer able to lock to vario-speed applications. However, that is only important for the DJ-s amongst us.
- There is another important argument against upsampling. The DAC-chip used (WM8741) offers 9 different settings for the digital input filter but 3 of these filters only works with sampling frequencies upto 48 kHz and three other filters only work up to 96 kHz. With upsampling these filter settings can no longer be used. And these filter settings are very interesting indeed, implementing low pre- and post-ringing algorithms as well as some high frequency roll-off algorithms that really do make a difference! Using upsampling would strongly limit the use of the possibilities offered by this advanced DAC-chip.
The SYMPHONY, like the OPERA and all other current CORDA amplifiers, besides regular stereo operation only offers one level of crossfeed. The current implementation of the natural crossfeed filter, which has a few improvements over the original design used in the first CORDA models, does not allow for an easy change of crossfeed level. The technical effords would be quite large.
Any other questions/remarks? Just let me know!