I just checked my e-mail and this was in the inbox:
Things are picking up steam here at LH Labs. While we've had one team focused on delivering Geek Outs to our backers, we have another preparing to launch an Indiegogo campaign, and another compiling all the data from our listening tests to finalize the Geek Pulse family. I have some fun news in this regard.
First, we've decided to include a couple of new inputs. For Geek Pulse and Geek Pulse S, there will be an AES/EBU digital input included that we hadn't planned on before. For Geek Pulse X, there will be an additional S/PDIF input that wasn't included in the initial design. By doing this, there's greater flexibility for all of our backers and future consumers, and it helps us to standardize the BOM's across the product line, making it less expensive to make chassis components, and easier to train our assembly staff. It's a win-win!
Second, after more listening tests, we've decided that we'll utilize a minimum phase digital filter in all the Geek Pulse DACs. It still needs to be fine-tuned, but our initial impressions are that using this filter minimizes an unnatural pre-ring that we've detected. We want to make Geek Pulse comparable to ANY DAC in the < $5,000 range. Our listening tests are done in direct comparison to our Sire DAC, which is our gold standard. We also compare it to other DAC's we've collected that we esteem to be overachievers. We think by holding Geek Pulse up against such stiff competition, everybody will be happy.
Lastly, we’ve discovered a campaign logic flaw. During the campaign, we used ab S/PDIF output as a stretch goal. Then, near the end of the campaign, we were asked to include femto clocks inside inside Geek Pulse to imporove jitter performance. We've found that these two goals are technically contradicting to one another. By adding an S/PDIF output (not an input), we need to insert one more layer of logic inside the digital audio signal chain. And has decreased the jitter performance, undoing the improvement the femto clocks added. Therefore, we've decided to cancel this feature and want to replace it with another one.
We don't take this lightly. Larry has been in constant communication with the Geek Force about the issue and, after a lot of input, came to this decision. What was presented to us by the Force as an alternative is adding one of the following options:
Mu Metal clock shields
Silver gain relay array
What do you think? Please visit Geek Force to cast your vote.
My vote goes for the user-selectable filter. I would be interested in comparing filters as only the Cambridge Audio DacMagic can do that as far as I know. I can't tell a difference between the linear and minimum phase filters with software under an ABX test.
Or maybe improved connectors would be a better choice in the long run for product durability.
I can hear some differences if I focus on specific instruments. I've compared filter 5 with filter 1 and at the time, filter 1 had a bit more "reverb" or "echo". Filter 1 and 3 was hard to tell apart. If I listen to the performance of the music as a whole, I couldn't tell the difference between the filters. However, it would require a lot of patience to listen to these filters. Stereophile did some experiments on these type of filters and published some results. Search for "apodizing" or "minimum phase" in Stereophile
It seems to me that these filters have very minimal impact in the sound quality, in which case I probably wouldn't bother with them after the first month of playing with them, and having better connecters would have been a better choice.Edited by miceblue - 4/5/14 at 1:52am