8 responses Add your response
The root cause of the problem is that the preamp section of the CAP-101 has an **extremely** high gain of 31.5 db. Meaning that it provides 31.5 db of gain when its volume control is set to max, which is how preamp gains are defined. It also has a slightly higher than average gain of 29 db in its power amplifier section. Also, the large change in volume you described that occurs between settings of less than 4 and more than 6.5 may reflect the fact that many preamp volume controls are intentionally designed to provide volume steps at very low settings that are much coarser than the step sizes that are provided over the rest of their range. Finally, the 2.2 volt figure for the maximum output voltage of the HAP-S1 may not be accurate; this document shows a 2.2K output impedance, but does not provide a spec for output voltage.
One thing that might be worth trying is connecting the HAP-S1 to the tape input of the CAP-101. It is conceivable that the CAP-101 **might** provide less gain from its tape input than from its other line-level inputs, although relevant specs from which that could be determined don’t seem to be available.
Aside from that possibility, as Yogiboy suggested you’ll have to insert an attenuator of some sort between the two components. In addition to the one he suggested, you might consider a Rothwell attenuator. Among the three attenuation values that are offered, my instinct in this case would be to go with the 15 db value.
On the other hand, though, the use of a passive preamp or passive attenuator between the HAP-S1 and the CAP-101 raises some concern about impedance compatibility, given especially the rather high 2.2K output impedance of the HAP-S1 and the very low 10K input impedance of the Schiit. I have measured the unspecified input impedance of the 10 db version of the Rothwell attenuator as being in the vicinity of 30K, and I would expect the input impedance of the 15 db version to be even higher. So my guess is that the Rothwell would be a better choice for this application than the Schiit.
Good luck. Regards,
Yogiboy, thanks for directing me to that product. Can you tell me whether, if I buy and use it, whether I then use it's volume control or that of the Classe?
Almarg, I've been reading your posts for years, and I am really grateful you took the time for such a long, thoughtful response. Because I'm functionally illiterate about electronics, I mistook the output impedance for the output voltage. I'll consider whether to try the Schiit or the Rothwell. If you saw my question to Yogiboy, just above, I can see from the Rothwell that I'd continue to use the volume control of the Classe. And I will try your suggestion for the tape input.
gs5556, that's a sound suggestion (no pun intended). As Almarg pointed out, the spec for output voltage may not be 2.2 (that might have been my misunderstanding).
If you determine that you need to stick some method of lowering the output into the line out of your Sony, I have a pair of the Rothwell attenuators that I could sell. Not trying to poach your thread, but the Rothwells are a bit expensive when you have to order them for the UK (which I did). I'm not currently using them. They were purchased to help equalize the output of a CD player and a phone stage that had a large difference. They work as advertised. I believe mine are the -10 db version, but I could double check if you are interested.
Kalali, a reasonable question. I bought the Sony HAP S1 because (a) reviewers and commentators praised its sound and ease of use, including its app for mobile devices; (b) I wanted a device where the music "lives" in the machine, as contrasted to being streamed; (c) I got a good price (30% off list), which made it more desirable than its competitors in the same price range (e.g., Bluesound and Cocktail); (d) I'm not using the HAP's integrated amplifier currently, so it shouldn't add anything to the audio path; and (e) at some point in the future, it can become part of a small second system because I can use its integrated amplifier.
By the way, it does really improve the sound of my music (which has all been ripped from 44.1/16 CDs). Essentially, the music sounds much clearer than when I use the CD player as a source. Instruments and voices sound better and more natural; the interior interplay is easier to hear. The difference is significant and immediately noticeable. My wife, who's never said anything about our equipment's sound previously, remarked that the music sounded better and that, in particular, singers sounded like they were in the room. The overall quality still depends largely on the underlying recording: better recorded material sounds better than lesser-recorded stuff, but everything sounds better.