No, too much for the sound $400 maybe. Try some silver or silver plated to get the gain back.

Marvellous cables at any price, capable of revealing great detail and astounding bass. Clean midrange that rivals any other high-end cable, sounds bright until after at least a few hours of break in.
Used in conjuction with other HT cables, will provide synergistic effect, and consequently rule out cables being the weak link in any system.

Well worth the price, though I haven't heard the Pro-11. Two thumbs up to HT for bringing such realistic prices and realistic sounds to the hi-fi world. Probably the best bargain in ANY components today. Improvements rival that of a careful and thorough room setup, and better an electronic upgrade.

This is the biggest farce in speakercables I have ever heard. All this talk about how great they sound must be a conspiracy! These cables sound harsh, have a skyhigh noise floor and are poorly constructed. Avoid at all costs. I cannot stress enough that I have never heard cables that made so little difference! These cables are comparable to 16 gauge Radioshack brand speakercable. If you are going to spend good money on cables look at Straightwires Crescendo or Taralabs Air 1 or The One. If I could give these cables minus stars I would.

I just finished reading all the reviews of all the Harmonic Technology interconnects and speaker wire that are posted on this site. I am a long-time audiophile as well as a dealer of a number of brands of high-end equipment. I love the hobby and am a dealer because who wouldn't want to do what they love? I will only say that I want my personal system to sound better than anybody's. I can get any gear I want one way or another, at cost or below or whatever. I have owned 58 different pairs of loudspeakers in my lifetime. I do not have a store, I do not have any employees so all the gear I get, I listen to like a kid on Christmas day. I never get tired of it. I have six demonstration systems up and running with, currently, 18 different pairs of speakers on hand. For what it's worth, I have full Harmonic Tech cabling in 3 of the systems, soon to be four, eventually six. Guess why? It makes each system sound its best. Period. I know my demo units. I have demoed this stuff over and over in each of four rooms and I know those rooms (it's my house). This wire just lets the signal through. I'm a happy hobbyist whenever I can find any component that seems to color everything in the chain the least. The HT products do this. Even the cheap ones.
Oh, right, I said cheap. Why would I like to sell less expensive cables to my customers if I could sell them more expensive ones? Just to make less money? Nope, because I want the customer's systems to attract other people to want to get a great system. I want my customer's systems to be great sounding so they enjoy their systems. It sounds kinda sappy, but I want 'em to like me and trust me too. So while I have all this other cable on the net for sale at rock bottom prices, I keep right on steering people to Harmonic Technology. Stop the search for wire. You'll be glad you did. These engineers are on to something. I loan the stuff out and my batting average, starting in March, is 28 sales, one return (The labeling on one strand had the arrow reversed so the guy thought it was poor workmanship and didn't listen to it).
So the Pro-9 Plus has spectacular sound if your system does. One guy on here seems to have a speaker problem, not a wire problem. Whether I use ribbons, subs, two-ways, or full range three ways, this speaker cable just lets the rest of the equipment alone. I sold some NEAR 50 ME mk II's one day that I just couldn't get anyone intersted in. I put some Pro-9 Plus into the system and I couldn't believe it myself. I figured it was the guy's recordings at first. I played my demo and almost laughed. It was just better, top to bottom. Cleaner, clearer, more transparent, lifelike. I haven't looked back since.

How anyone can rate this cable one star is beyond belief. They either haven't really listened to the cable or they don't know what good is.
The entire line of HT cables are excellent sonically and an excellent value $$$. They have replaced much more expensive cables in my system because they just flat out sound better.

Don't listen to these one and two star reviews. Listen to the cable. You will be glad you did. HT gives a 30 day in home trial.

5 stars for their entire product line

Bought the Pro 9 Plus Biwire 3 weeks ago. They didn't sound right for the first 30 hours (thought I made a major mistake). Now having played it for about 35 hours, it seems to get better and better! Bottom pitch and definition beginning to surface and the highs are getting sweeter. I guess the only way to know if you like the cables is to listen to these cables after they've been properly burned-in.

With all the wonderful comments posted about HT's interconnects and cables, I hesitate to include my essentially negative impression. I auditioned HT's Pro-9 Biwires, and Truth-Link interconnects. My system consists of B.A.T VK-60 (tube amp), VK-3i preamp, and VK-D5 cd player, and Dunlavy IV speakers. I had been using Tara 2nd gen speaker cables, and Tara Decade Interconnects. The exclamatory praises for the HT's whetted my interest, so I ventured to obtain the aforesaid. Also, when they arrived, I had on hand Nordost SMP biwires, for audition. The difference the HT's provided was one that was interesting, but not musical. The illusion of heightened detail was created by the interconnect between the source and preamp, which required that I increase the gain by 50% to match the volume I had been able to get using the Tara Decade. This means the interconnect suppresses certain aspects of the signal from the source. It also means the extra gain was needed to amplify what the HT interconnect was not suppressing. This greater signal strength was focused into certain images, the result being the sense that a sound, e.g., a trumpet, was more concretely located in a certain area of the soundstage. The downside was a significant loss of detail, (I call it 'hair') off the notes, so the sound seems bald but bold. A similar sort of gain uptake is required using XLO reference interconnects between the source and the preamp. A similar enhancement of the sense of localization in the soundstage and of discreteness of the output from the instrument. But despite these interesting effects, after several days of listening, I was very aware that the overall effect was less musical, less enjoyable as music. What proved actually to be the cables that were an improvement over the Tara 2nd gen cables were $5 @foot Naim wires. There was absolutely no mistaking the huge improvement. Bass much more evident and natural sounding, and much, much more musical. Restoration of detail gave great depth to the sound wall. I fully intended to make a purchase of the HT's when ordering, but could not deny the decrease in music enjoyment, and with regret and disappointment (the reviews seemed so unanimously approving, but unfortunately, when I went over them again, they extolled the sound, but could not say the music was better), returned the invoice with the gear.

I'm not going to dispute Len's preference, but the 50% gain decrease is just ludicrous, IMHO. I have compared the Pro 9 and Truth Link to Goertz MI2, Triode, and Kimber 8TC and Silverstreak. Under no circumstance was there a reduction in gain with the HT cables. If the HT cables had network boxes like MIT, then I would be willing to entertain the possibility of what Len is suggesting.
FWIW, I had to play my system at lower volumes with the HT cables, but, I was able to narrow the cause to the HT AC11 power cord, which rendered a noise floor free-fall. If Len claimed that the HT cables increased the noise floor, I would be content with that explanation.

review of Truth Link interconnects (1 meter, single-ended, $249 retail)
I can't believe it either. Stunning clarity! I've been reading reviews of these cables for a while and finally got a chance to try them. The only question left is what I am missing not using their speaker cables too.

Len. I've had the problem you described with speaker cables but never interconnects. Once I returned an Audiodyne silver speaker cable because of a lack of output only to find that the problem was a lack of sufficient AC current to drive the higher impedance cables(Goertz are only 4 ohms). Once I put in 2 dedicated AC lines the problem disappeared. The fact that the problem repeats itself with the XLO suggests an impedance mismatch. Again, I found no impedance problem with Tara Master Gen. 2. Call the manufacturers and trace the problem. It's not the HT unless it had a short.