Changes that made a difference (in order of effect).


Here are the changes I’ve made to my system in the last six months -

Speaker placement: I’ve been moving my SF Auditor M’s around trying to get the best imaging and smoothest frequency response. They are currently 30” from the front wall, 67” from the side, 76” apart, and toed in ~ 15 degrees. I have moved them back and forth in all directions as well as shifted my seating position trying to optimize the room/ speaker interaction. This is a very time consuming study. REW software helped; being able to see changes in distortion, time domain and frequency response makes it less ambiguous. It now feels like it’s as good as it’s going to get. BTW, the mad NASA engineer was right. Speakers closer together, closer than you might otherwise think, is better.

Diffusor: I built the Arqen lean diffusor designed by Tim Perry and put it on the near side wall to improve clarity. (Unfortunately, my room set up is not symmetrical.) I have lots of constraints in my mixed use living/ listening room. So a diffusor doubling as wall art is a win/ win situation. (See photo in my virtual system.) Initially, I tried the model 4 but in the end I went with the flat version. Moreover, I made it out of walnut and reduced the height to 13” instead of the recommended 48” for improved WAF.

The “Master Handbook of Acoustics” recommends absorption at the first reflection point and Floyd Toole recommends nothing on the wall at the FRP. Recommendations also vary depending on whether it’s a studio control room or a listening space. The diffusor is 8’ from my listening position. I don’t know if the lean diffusor is actually diffusing or just attenuating. What is noticeable is how much clearer China Forbes’ voice is when playing Pink Martini. YMMV

Preamplifier clipping: This issue is discussed at length in the Harbeth user group. http://www.harbeth.co.uk/usergroup/forum/the-science-of-audio/amplifier-matching-mismatching-and-cli... Willemj pointed me in that direction a while back. Previously, my volume setting was around 9 o’clock for ~70 dB sound level, not much useable range on the volume dial. I added -10dB attenuation to my Marantz CD player (one of the default settings) and that shifted the volume setting upward to around 11 o’clock. Previously, listening to Jeff Buckley’s “Hallelujah” there were two points in the song where the guitar goes twang and my ears would go Ouch! Now, much better.

Wall outlet: This is a tweak that others swear by but I can’t be sure of. After seeing what extreme measures Folkfreak went to manage his incoming power, I wondered about my standard residential set up. I unscrewed the old back stab wall socket that my system is plugged into and pulled on the wires. They easily slipped about 1/8” before grabbing. Hmmm...not a very positive connection. I replaced it with a Hubbell 8300H (old un-plated version) I got on eBay. It seemed like the bass response was better (maybe) but I couldn’t confirm by A/B testing the outlets. 1) it takes at least 10 minutes to replace a socket (too long to remember) and 2) I cannot recreate the 30 year old marginal connection to the back-stab outlet. In any event, I’m happy with the very positive connection provided by the Hubbell plate and screws.

I’m done (for now). These positive changes are mostly from shared learnings by forum members for which I’m grateful.

What recent changes have you made to improve the sound of your system?

mikexxyz
I built a noise filter for my audio system. I had no idea how much noise was coming in my 🏡. Clearer, cleaner, blacker background, more detailed sound. 😎
First and foremost, speaker positioning. Some are more sensitive to that than others obviously. Next amplification and source, fairly close. Cables, interconnects, meh.....
Biggest improvement in my system was swapping out an old B&K PT5 preamp for a Parasound Halo P5 preamp. Amazing difference, especially at lower volumes.

Jeff
1.)  Getting the TDSS Level 3 upgrades for my Nuforce Ref 9 V3 SE mono amps--the already good sound of the Ref 9's was improved by a considerably margin with live dynamics, authoritative, articulate bass, and you hear things on the highs that were not nearly as audible, and the mids are just spectacular.  Thanks Bob Smith.

2.)  Getting the rods cut much shorter on my Sistrum rack so I now have 2 racks where the tops with equipment sit a foot below the midpoint of my speakers--much more stable and the soundstage has improved about 50% in precise location and sound of the instruments.

3.)  Putting a Core Power Tech 150 PC on my TRL DUDE--made the sound more organic, clearer, and more dynamic.

4.)  SR Blue fuses in my MW 5400, Whest 3.0 RDT SE phono, and Nuforce Ref 9's--more clarity with beautiful sound.

5.)  Doing the Star Sound trans mod to both my MW 5400 and my DUDE.  Increased the sound performance by 25% in all areas.

6.)  Adding the Synergistic Research UEF panels and dots to the room.  Made the speaker disappear more, solidified the center image, and added clarity and more beauty to the sound.

7.)  Adding another CPT-150 to my Synergistic Research QLS-6 power strip.  Lowered the noise flow thus improving the clarity and dynamics.

COMING--Will do 3 of the High Fidelity MC 0.5's and THEN, the awesome Perfect Path contact enhancer to all contacts.  The PPTC may become my biggest sound change.  Beating the TDSS upgrade will be a trick though.
In the past three years:

1)Replaced my Classe CP-60 preamp with a DEQX HDP-5, which in addition to serving as a preamp provides numerous signal processing functions including room correction, speaker time alignment, DAC functionality, A/D converter functionality, and DSP-based equalization.

2)Upgraded my phono stage from the phono section of a vintage Mark Levinson ML-1 preamplifier (accessed via tape outputs) to a Herron VTPH-2.

3)Replaced my Soundsmith re-tipped vintage Grace F-9E Ruby phono cartridge with an Audio Technica AT-ART9.

4)Replaced my Stax SRM-1 Mk2 solid state headphone amplifier and Stax ED-1 Diffuse Field Equalizer with a Stax SRM-T1 tube headphone amplifier. A huge improvement, but listed fourth because it just pertains to headphones. The headphone I'm using is the Stax Lambda Pro I purchased in the 1980s.

5)Added an Adona Isolation Platform for the Herron phono stage.  Can't say what if any difference it made, as I installed it at the same time as the Herron.

6)Replaced a BrickWall surge suppressor/power conditioner with a combination of an Audience aR2p, a Shunyata Venom Defender, and a Wiremold UL210BC power strip to expand the number of outlets.  Can't say what if any difference it made, as some of the other changes were occurring at around the same time.

Regards,
-- Al