PureAudioProject Quintet15 Horn1 open-baffle speaker system

Improving upon the stock speaker

PAP has made it easy for customers to tune the Quintet15, and the most favored methods are the easiest: upgrade the capacitor, procure a favored wiring, and try the alternative settings of the jumper to run the crossover in Series or Parallel. First, addressing the option of Series or Parallel operation of the crossover, I find the Series setting more favorable than the Parallel setting. It took me only moments to hear the more shallow, restricted, less vibrant and less energetic character of the Parallel jumper setting. I cannot imagine any rig in which I would prefer that setting, but regardless of what I can or cannot imagine, I will try that setting with every new system I set up with these speakers, because a surprise could occur. Whenever a new rig is established it is incumbent upon the owner to try all permutations, as one never knows absolutely which configuration will be superior. I would, however, expect the Series setting to be preferred in nearly all my systems.

The stock capacitor, while giving acceptable performance for a speaker that is not priced as a bespoke product, can be improved substantially. As I had on hand the Mundorf Evo oil filled capacitors that were used with the same horn in the Trio15 configuration, I knew they would work with the Quintet15. I do not know all the nuances of the specifications of capacitors, but I suspect the replacement caps being not the 250µf of the stock caps, but 600µf, made a substantial difference. The great joy of better caps is that the speaker becomes smoother and more tonally rich! Those are such important characteristics to yield a sense of luxury, and the horn accommodated the oil filled caps like a fish to water. This is such an inexpensive upgrade, relatively, that I urge owners to look into it. I believe that there is one level of capacitor improvement available through PAP, but if one desires, more expensive and better performing caps can be found. I secured mine as a clearance item from a speaker manufacturing/repair facility that had them sitting around. They were about $200 for the pair, but the improvement was well worth the expense, so much better than tweaks I have tried that exist outside the signal path! The warmth that these caps brought to the horn made it blend even more beautifully with the bass drivers.

Placement of the speaker is an expected method to massage the sound quality. As discussed previously, I was surprised at how agreeable this speaker was in terms of placement toward side wall boundaries. I have not discussed the positioning of the speakers relative to the front wall, but I used them no closer than 5’ out from it. I did not think it advantageous to push them back into the corners; however, owners may wish to try it if they crave even more bass reinforcement. That could come with some unwanted anomalies in terms of strong reflections off the front wall, but perhaps some aggressive room treatment of the corners could moderate it.

Toe in is such a personal decision, and I have settled most often on an angle slightly wider than the respective ear, a method that has served me well over the years. I find that with compression drivers, ring radiators, and similar high intensity drivers, if I aim them at my ears, they seem pistonic, like sonic jackhammers. Putting them off axis allows a bit of edge to be taken off, and the bass to be more noticeable.

There is a crucial maneuver to explore in order to maximize the performance of any enormous speaker: forward baffle slope. With any speaker nearly six feet tall or taller, I find a distinct advantage in angling the baffle slightly forward so as to put the front plane of the speakers more in line with the ears. This is especially so if the speaker has woofers positioned above the listener’s ears. Tilting a big speaker with separated woofers has the marvelous effect of pulling the output of those drivers into line with the ears. The bass becomes far more taut, clean, and pleasing. In addition, when the speakers are toed in appropriately, not only is bass positively impacted, but the entire center and mid-center of the soundstage is resolved to a higher degree; the improvement can be striking!

When I was first reviewing the Trio15, I found better coherence and bass driver integration by tilting the speaker backwards because the horn sat slightly below ear height. With the Quintet15, I bring the speaker forward. Why do so if the baffle is curved already? Even with the curvature, not all the drivers are equidistant and the horn may sit above the listener’s ears. Arranging the speaker to preference in both the horizontal and vertical axes enhances the experience. I do this as a matter of habit with the Legacy Audio Whisper DSW Clarity Edition, the Kingsound King III electrostatic speaker, and also with the Quintet15. All it takes is perhaps a 0.25” thick piece of wood or metal to lift the back of the speaker. Try it, I think you will love the method!

The last of the methods of contouring the sound of the Quintet15, apart from ancillary electronics, regards cabling. I have spoken at length in my reviews about two methods I use continuously, the first of which is the Schroeder Method of Interconnect Placement, in which two interconnects are paired through use of Y cables, thus making a double IC for each channel. I am not going to delve into an extended discussion of this technique here, but interested parties can begin by reading my seminal article seen here:https://www.dagogo.com/audio-blast-schroeder-method-interconnect-placement/

The Schroeder Method of IC Placement has received favorable response from the USPTO, and is anticipated to be issued the patent shortly. As I do not have the ability to test every system in existence, I have always erred on the side of caution by saying it is a “do at your own risk” activity. Caution should be exercised when using interconnects with high capacitance as that may present a threat to certain amplifiers. The reader is instructed to speak with their component and speaker manufactures if they have any questions. I have used my method with many cables and systems and have never encountered an issue, but have elevated the system performance in every instance.

The second non-intrusive cable method, one that also does not involve changing the Quintet15’s build, involves doubling of speaker cables. Again, I do not recommend this with passively networked speaker cables; in fact, I do not recommend such cables at all. Parallel or doubled speaker cables simply means laying two separate cables atop each other, with the leads perfectly matched, positive with positive and negative with negative, at both the speaker and amplifier ends. A mistake may mean a damaged component, so be deliberate in your actions! I also do this method as a matter of habit with all single-wired speakers like the Quintet15. As with nearly every other speaker I have used, holistically the performance is enhanced in every parameter. For this review I have used doubled/parallel Iconoclast by Belden SPTPC (Silver Plated Tough Pitch Copper) Speaker Cables, not typical bi-wired cables, but two individual wires placed in parallel configuration. Note that I recommend serious audiophiles work with entire sets of cables from manufacturers and eschew mixing brands and models during the assessment phase of working with new cables. The Iconoclast cable line is ideally suited for the Quintet15 speakers.

Finally, as regards the internal wiring from crossover to drivers in the Quintet15, the supplied copper wiring is made by Klotz, a German Pro-Audio supplier of cable solutions. Here the audiophile can go crazy, spending a sizable portion of the entire speaker’s cost if they wish. I do not recommend that. These speakers deserve a pure signal transmission, and one of the purest I have found is with Iconoclast by Belden cables. I would dearly love to hear these speakers with a complement of the top line Iconoclast wire, but the relatively high cost of these cables and the amount needed to rewire the Quintet15 is prohibitive for a speaker at this price. If you are awestruck with the PAP line and if you would spare no expense to get the ultimate experience, then seek Iconolcast’s top cables to rewire the speaker. But for most of those who are not inclined to spend extraordinarily, Iconolcast has other models with the same AWG and geometry, but with different conductor material and, consequently, lower pricing, making them a compelling choice for such a project.

I am almost never completely out of options to optimize an audio system. Having plowed through dozens of tweaks and methods, and having drawers full of ancillary items, I can always find some way to tune a rig further. In this instance I returned to the appreciated upgrade that I used with the Trio15, associated with a trip to Radio Shack just before the chain’s demise. I procured on discount a spool of 10AWG silver/copper braided speaker cable, which I used on the entire Trio15 as an upgrade. It was efficacious, and it helped to integrate the horn more smoothly with the twin 15” bass drivers.

I returned to that mixed conductor cable and found I had just enough to reach from the Thrier crossover to the horn in the Quintet15. Once again, it brought some needed warmth and finesse. I encourage those who are seeking a slight shift in temperament of the speaker to boldly try different cables. Ideally, as with systems, one should work with an entire set and not simply wire up different drivers with a variety of wires. However, already having done such a change in the prior iteration of the speaker, I knew what the effect was likely to be, and it was not disappointing. If I am able to procure Iconoclast cables for a continuation of this experimenting, I will give an update.