Kinki Studio EX-M1 200wpc Integrated Amplifier

Pts, the line-level inputs of powered subs generally have low impedances, typically in the area of 5K to 20K.  Before proceeding down this course, it would be prudent to inquire as to what the output impedance of these pre-outs would be, and if Alvin would recommend them as being suitable for driving such low impedances.

Good luck.  Regards,
-- Al 

I was under the impression that some watts were wasted if one had to crank up the volume before hearing something.

That would be true if the combination of amp gain, preamp gain (if there is a separate preamp, although of course there wouldn’t usually be one in the case of an integrated amp such as this one), and source output voltage is insufficient to drive the amp to its maximum power capability even with the volume control at max.

That can happen in some situations, and in fact I’ve been discussing just such a situation in a recent thread which involved the possibility of using a Herron phono stage to drive a certain power amp via a passive preamp which provides no gain.  But that would be a fairly unusual set of circumstances.

Best regards,
-- Al

Nonoise, to clarify a minor point, the gain of the amp affects the position of the volume control at which the first watt occurs. But the first watt is the first watt, and will produce the same volume with a given pair of speakers whether it occurs at a 9 o’clock setting of the volume control with a high gain amp, or at a 3 o’clock setting with a low gain amp.

On the other hand, of course, the first watt of two different amps can sound considerably different.

Best regards,
-- Al

Thanks Nonoise.  That's good to know.  I'll be watching for further reports about the sonics of this amp from you and others.

Best regards,
-- Al

OK. So if I understand correctly setting the volume control to around 30 on a scale of 0 to 255 seems about right on the recordings you’ve tried so far.

That suggests the gain is fairly high, and means that the sensitivity spec I referred to in my post dated 7-8-2018 is probably inaccurate, with the sensitivity numbers being lower than indicated.

It also means that using the amp as a power amplifier, in conjunction with a separate preamp or other component providing significant gain ahead of it, might be problematical. I had been toying with the idea of using this amp as a backup for my VAC power amp, and/or rotating it with the VAC now and then as a fun experiment or for a change of pace. (Using the Kinki as an integrated amp without a separate preamp would not be appropriate in my system, because I would not want to be without the signal processing and other functionality of the DEQX HDP-5 I use as a preamp).

Thanks again. Best regards,
-- Al

Great news, Nonoise. Congratulations!

Regarding a question I posed earlier in the thread, does the gain seem to be either particularly high or particularly low, as judged by what part of the volume control’s range you find yourself using? As I mentioned in my post on 7-8-2018 there seems to be conflicting information regarding gain, none of which seems consistent with a moderate or typical value.

Also, in my post dated 7-7-2018 I had wondered about the possibility of transient intermodulation distortion resulting from what might be incorporation of a lot of feedback in the design. I think a good test for that would be well recorded solo piano music having lots of sharp transients.

Enjoy! Best regards,
-- Al

Another question I’m curious about regarding this amp concerns gain. Sensitivity is specified as follows:

Input Sensitivity: 2.25Vrms - 3.6Vrms

I’m guessing that 2.25 volts is for the unbalanced inputs, and 3.6 volts is for the balanced input, as I don’t see any means of varying the sensitivity in the internal or external photos. Given the 215 watt 8 ohm power rating those sensitivities can be calculated to correspond to gains of approximately 25 db and 21 db respectively. Which seem like very low numbers for an integrated amp, and perhaps too low to be optimal with some combinations of vinyl sources and low efficiency speakers.

Yet the review contains the following statement:

Who actually needs 200 watts with 26dB of voltage gain in just the line stage followed by another x 20 amplification factor in the power stage? Very few. Because the EX-M1 hits its torque already in first gear, that number is mainly for bragging rights, peace of mind and yes, the rare customer who really does own that boat-anchor load to tap such power and gain.

That would mean a total gain of 52 db, which in contrast to the calculated numbers would be very high for an integrated amp. And probably too high to be optimal with some combinations of digital sources and high efficiency speakers.

Just wondering how to reconcile this apparent discrepancy, while having some concern that all of these numbers may be a bit extreme in one direction or the other.

Regards,
-- Al

David, thanks for calling this amp and this manufacturer to our attention. I read the review, and it certainly sounds like a remarkable value at its price point.

The only thing that strikes me as being a possible concern is the combination of its extremely high specified damping factor of 2000 (which is unheard of as far as I am aware for an amp that is described, per the reviewer, as not being class D), and (to a lesser extent) the low THDN spec of <0.006%. Those numbers suggest the likelihood that the amp uses substantial amounts of feedback, which might mean that the subjective perception of speed and detail that is reported may be significantly contributed to by TIM (transient intermodulation distortion).

We shall see. Nonoise, best of luck with your purchase.

Best regards,
-- Al