What makes the biggest difference in sound quality?

As everyone has pretty stated everything matters and is important, but that is where i differ with most. Most feel speakers is the most important and not to say they aren’t they for sure are but i believe in putting more emphasis on the front end. Preamp, phono preamplifier or section, amp, source equipment, cartridge, turntable, tonearm, digital playback, speakers then cables. Yes quality of power and power cables also make a big difference, but speakers are down on the list for me because you’d be shocked how good even average speakers can sound with great equipment, where as great speakers with modest electronics will sound very mediocre to poor. Not to mention the importance of setup and calibration ! Speaker placement is the single most important aspect in getting good sound.

I'll go with the Linn philosophy, the source. I'll also agree with a previous post that even lower budget speakers can sound great with more upscale electronics. Lastly, power matters. A dedicated line, a good power conditioner,  and power cables do make a difference. 

room

@ ted_denney OP

I have heard systems with a set of cables all from the same brand and not knocked out with the result. In one particular instance where all Audioquest was used I introduced a DIY power cable to try instead of the Audioquest PC which made a very noticeable improvement. I’m not saying this would happen in each and every case but just to point out that a ’set of cables all from the same brand’ is not the panacea you make it out to be.

For those interested the DIY cable I refer to above was made from Oyaide Black Mamba V2 with Furutech’s best connectors. This is a killer deal and works with all digital components and amps. It's outperformed many very expensive pretenders!

In fact I’ve heard well set up systems $20,000-$30,000 with a full loom of cables, a full loom of electronics, proper speaker placement and mild acoustic treatments, outperform systems in the deep six-figure range with mis matched cables and components.

I notice also that you downplay the importance of proper room treatment, evidenced by you referring to ’mild acoustic treatment’ when in fact room treatment is paramount for optimising any system regardless of cost. IMO there is a way to get your hypothetical $20,000-$30,000 system to outperform a deep six figure system, and room treatment, that is proper treatment, not mild treatment whatever that vague and nebulous statement means, that complies with the target of achieving an RT60 across the full spectrum in the appropriate time for the room of concern, which on average is around 400ms. No tweaks including full looms can do that.

Without the room being tamed most tweaks are difficult to impossible to hear. By this I encourage all still reading to consider trying to make a decision on different cartridges by carting your turntable, amp and speakers into the bathroom with all hard surfaces. The amount of sound reverberating around the room would obscure and smear all the detail and you would probably choose the dullest cartridge to compensate.

Your clever initial and subsequent post just comes across as a thinly disguised sales advert.

Cables cannot make a difference comparable to the huge transformation in the room acoustic...Like just says lemonhaze...

No one selling gear or cables want to disclose that simple truth...

Acoustic passive treatment and especially mechanical active control with Helmholtz method WOULD KILL any desire to upgrade in most people who will implement it... And changing cable is a MINOR improvement, only seems to be a major improvement when someone has never correctly adress the room or had synergy gear problem already ...

Anything else is marketting or ignorance or the two....