Integrated amp recommendation around 3k (I need more power!)

smrex- Yep!

However, it does seem that the amp runs out of steam before I’m even able to generate peaks of 80db at the listening position.

Hi Scott,

My suspicion is that what is mainly running out of steam is the speaker, not the amp. The speakers have specified power handling of "50 watts program." Which presumably refers to the maximum amount of power they are rated to handle on the peaks of what the designers consider to be typical musical material. And their continuous power handling capability, were it specified, would be considerably less than that.

Putting more power into a speaker than it can comfortably handle will result in some combination of increased distortion and thermal compression, which among other things would result in a perception of reduced dynamics.

Also, regarding the CJ integrated amp that was suggested, I would have some concern about the suitability of its 10K input impedance with the output impedance of your phono stage. I found an indication that the nominal output impedance of the phono stage may be 500 ohms. However since it is tube-based, and most likely uses a coupling capacitor at its output, its output impedance at deep bass frequencies could very conceivably rise to a few K, which would result in significant deep bass rolloff in conjunction with a 10K load. On the other hand, though, that might not be perceivable with these particular speakers, given their limited deep bass extension. But why risk compounding that limitation?

Best regards,
-- Al

Anyone using a B.A.T. integrated amp ? Which one can you suggest?

@almarg As always, thank you for being so generous with your knowledge and for looking up the specific specs of my gear.  (Maybe I should be looking at a bigger, more efficient Harbeth...). In any event, I appreciate the words of caution with the CJ.  Could you give me some idea of the input impedance that would be more reasonable with the Croft?  I've often heard 100/1 as a minimum ratio, so I'm assuming at least 50kohms would be a target?

Thanks again!
Scott

You're welcome, Scott.  The majority of tube-based components providing line-level outputs utilize a coupling capacitor in series with their outputs, which typically results in their output impedance being highest (within the audible frequency range) at 20 Hz.  If the output impedance at that frequency is known (which will usually be the case if Stereophile has reviewed the product) a load impedance 10 or more times greater than that value will usually be safe.

If as in this case only a nominal impedance is known (nominal impedances usually being specified based on a mid-range frequency such as 1 kHz), I would recommend a factor in the area of 50 to 75x.  So for what is apparently the 500 ohm nominal output impedance of the Croft a load impedance of 37.5K or more would certainly seem comfortable.  And at around 25K or less I would start to feel a bit uncomfortable, especially if you envision the possibility of eventually changing to speakers having significantly better deep bass extension.

Best regards,
-- Al