[mick wolfe]

By 'detail' I assume you mean resolution?  I don't know if anyone wants more detail.

To get the trifecta of better resolution, dynamics, and transparency (and who doesn't want all those?) I agree with Charles.Disagree with this. The A-21+ is the only thing I'd keep from that list of gear as it's more than capable of running the very difficult loads those speakers place on the amplifier. I'd sell everything else, not replace internal parts in equipment, and get the best source you can afford, possibly a dac/preamp that can run the A-21+.

Apologies to the OP, this is what happens when you ask for advice. 

Oops, My bad. Was actually mixing up the A21 with the A23. Two completely different animals. Yes indeed, the A21 would not appear to be the problem, but I'll stick with my try a different pre-amp statement. And then again, maybe those recommending a change from the Spectra 1100 might be on to something. Totally agree on NOT changing any internal parts. That would clearly appear to be a "fool's errand".  Once again, the old standbys of room treatments and speaker positioning as being the first choice of options to try.

[plnow1]

Good cables can make a significant difference from not so good stuff, then I would touch the internals

[Early B.]

OP -- you can change every cap, resistor, and cable you have and it won't fix your problem. Replace your speakers.

[kmmd]

OP, everything in your chain matters.  Replacing parts may help, but in the end you can mod a Pinto or a Gremlin all you want, it won’t ever be a Pagani.  For example, I modded my Marchand XM-44 crossover with everything conceivable (BlackGate bypass caps, OPA627s, Burson Vivid 6s, Bybees and SR Orange fuse).  It didn’t come close to the Pass Labs XVR-1 crossover that I had. 

I’d start with the source, DAC and low level components first and play with cables last.  Speakers are very important.  Do not add equipment such as an equalizer, as it will will color the sound more.  Just MHO.

[rollo]

I have the following components in my hi-fi system. And the sound has a dip in the vocal midrange followed by a peak in the treble then a roll off in the upper treble.
But that roll off would be the Acoustats, as they naturally roll of at about 16k.

TRANSPORTS & DACS-OPPO BDP - 105D DARBEE EDITION - THETA DATA II-TRANSPORT - THETA DSPro PRIME-DAC - PIONEER ELITE DV-45A

PRE-AMP - NUFORCE HAP-100 - HEADPHONE AMP/PRE-AMP

POWER AMP - PARASOUND - A21+

SPEAKERS - ACCOUSTAT SPECTRA 1100 ELECTROSTATIC - I also made some custom speakers using 15" professional bass guitar speakers-GRS PT5010-8 10" PLANAR MIDS -
and GRS PT6816-8  8" PLANAR SLIM TWEETERS- While these sound better, there is still that thinness or dip in the midrange followed by a treble peak
CABLES - KIMBER KABLE 8TC-3 METER SPEAKER CABLE - WIREWORLD-LUNA 7 INTERCONNECTS - HAVE CANARE 75 OHM DIGITAL COAXIAL CABLE - QED PERFORMANCE COAXIAL CABLE

So, I figured that if I replaced the capacitors with much better quality ones starting with the Theta Data II CD Transport, that would cut out the harshness from the transport, smooth out the response and yet still be transparent and detailed. Then, if I still needed more refinement, I could do the same thing to the DAC. And then to the Pre-Amp if I need to.
Because, I have tried over a dozen different interconnect cables. And while they do make a difference, none of them as of yet make a difference in the frequency range that I need to address. Not without knocking down the level of detail by quite a few notches.
So, I think that upgrading the capacitors would cost less and have a much bigger impact on the sound.
What do you think?

 Your DAC and transport are an older design. Much improvement over the years in DAC design. Theta had a bright and sometimes hard presentation. I would start with that. Try moving your speakers as well to tame top end. The preamp is questionable as well. Speakers just fine. Have fun

charles

[Freo-1]

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