Stack Audio Products Review

After reading a number of rave reviews of the Stack Audio products I decided to try them and see if they could improve my system. Stack offers a 30 day money back guaranty and they even cover return shipping which is made very easy as they will email you a return Fedex Label.

 

They have several products:

 

A Turntable Vibration Mat

A Record Stabilizer Clamp

A SmoothLAN Ethernet Filter

Component Isolators

Speaker Isolators

 

I don’t have a turntable so I did not order the first two items. Their unique patented isolation products absorb and isolate components and speakers by decoupling them from whatever they sit on and absorb any vibrations. The reviews for these products while not numerous have all been exceptionally positive so I was very much anticipating trying them in my system.

 

The first to arrive was the SmoothLan. This small rectangular box sits between your Internet access and your streamer. In my system I have a Wifi Extender connected to my EtherRegen Switch which is then connected to my Aurender N20 via a DH Labs Reunion EtherNet cable. I connected the SmoothLan between the switch and the Aurender. The SmoothLan includes a short quality EtherNet cable to use as a connector. Some have connected the SmoothLan before the switch but in general most do as I did. Some even have a SmoothLan on both sides of the switch.

 

My initial reaction was that the SmoothLan did in fact smooth the signal. It seemed to smooth the high end but in my system at the expense of high frequency extension and openness. It seems to take some of the atmosphere and air away. So I removed it for a while. After a day or so I tried it again with the same results. I think that it was most likely adding additional filtering that I don’t need. The EtherRegen, the Reunion Cable and the Aurender all do an excellent job of cleaning up the Ethernet signal. So this product will likely be of benefit to those who do not have a quality switch, cable or streamer that are already cleaning up the signal. I contacted Stack and arranged for a return. They emailed me a label and I dropped it off at the local Fedex. BTW this product is about around $250.

 

The next to arrive was a set of four Component Isolators. These approximately  2“ diameter by 1” high disks were more of a challenge to audition. I first placed them under the Aurender N20. I decided to placed them between the front and back Aurender feet on the sides. Some reviews said placement wasn’t critical while others said toward the sides or front as best. Anyway in this position the sound was disappointing. The highs were suppressed but they were also refined. I really don’t like anything that suppresses extension even if other parts of the response improve. I removed the Isolators from the Aurender and placed them under my MSB Discrete DAC. Here the sound was slightly better but still not to my liking. I next moved them to one of my DAC power supplies and found no difference than having them under the DAC. Finally I placed them under my Accuphase P4600 Amplifier. This gave me the best response so far. The highs were still not as open as I preferred but they were very refined and smooth and the bass improved. I kept them there until the next product arrived.

 

Next up were the AUVA Speaker Isolators. I received two sets of four of there Model 50. They have 70’s and 100’s which offer more isolation at additional expense. I ordered them with felt pads as I don’t like spikes and I planned to put them directly under my Harbeth C7ES-XD speakers which sit on Wharfdale Linton Stands. In this location with the Component Isolators still under the Amp strangely I found the overall sound to be somewhat brighter than I like. Bass was very good. Midrange was clear but the high end especially on strings was too bright. I then moved the Speaker Isolators from under the speakers to the bottom of the stand. I replaced the Linton stand’s feet with the Speaker Isolators using the bolts I had ordered that specifically fit the Linton stands. Stack offers a variety of screw bolts. You just have to tell them what speaker or stand you have. I had not ordered the spikes so the stands and Isolators were sitting on the carpet. In this configuration the sound was less bright but still not to my liking. After listening for quite a while and missing that smoother high end extension I moved the Component Isolators from under the Amp to back under the Aurender to see how they would sound there now that I also had the Speaker Isolators. This time I placed the Component Isolators under the very corners of the Aurender. The Aurender feet are recessed about two inched so it was easy to place them on the corners. This gave me the best response so far. After another day I was still sensing that I was not getting that openness I craved so to make sure I was not imagining everything I removed the Speaker Isolators and the Component Isolators and yes there it was that openness and upper frequency extension returned. But funny thing is after listening for several hours I realized two things. I missed the upper end refinement the Isolators provided and the deeper bass they offered. Also I started to notice that even though I had more openness without the Isolators it was at the expense of refinement. Totally frustrated I was at a loss as to what to do. Then I remembered that I had never tried the Component Isolators thought maybe the Speaker Isolators under the stands without spikes may be compromising their performance. So after making this change the magic finally arrived.

 

The bass was solid, the midrange clear, warm and lifelike and the highs were both extended with air and openness but also refined. In addition the images seemed to be more defined in the soundstage and when I increase volume I can hear a slightly wider stereo image. Also because the sound is cleaner and more defined I can play tracks at about 1 or 2 db loader than normal without any problem. Phew! What a relief. Finally a configuration that worked. So I will be keeping both the Component and Speaker Isolators.

 

I had also ordered an alternate isolation product to try: The Soundeck Mini MKII. These are flat circular thin metal disk absorbers. I ordered 8. So now I slid four under the feet of my MSB DAC. The effect was subtle but it slightly tightened and deepened the bass. At $13 per disk they are an economical way to quickly improve the sound. I tried putting the other set under my Amp and it was too much of a good thing. Similar to when I put the Component Isolators under the Amp it just dampened the upper frequencies. The Accuphase Amp has fairly large feet that are about 2” in diameter and almost an inch high with large rubber type inserts so it may already be handling vibrations effectively and dose not need any more dampening. So I removed them.

 

BTW the Component Isolators are under $300 for a set of four and the Speaker Isolators are around $500 for a set of eight. The Component Isolators come in three weight support sizes each priced the same. The Speaker Isolators come in three models: Good, Better, Best. Each with increasing isolation and control as the price increases. I ordered the Good one: Model AUVA 50.

 

Hope this is helpful to those interested in vibration control and component decoupling. There are a lot of products and some very expensive but either the Stack or Soundeck offer a very reasonable alternative that works if you have the patience to experiment. I’m retired so I could spend hours each day trying different configurations and listening to my list of reference tracks over and over. You may not have that luxury.

 

One final note. While I was going through this time consuming audition I thought about those reviews where the reviewer instantly found impressive improvements when using these products and wondered why didn’t I. I think it has to do with two things:

 

First my system is very neutral with a slight emphasis on warmth. Second my room is also warm with carpeting, plush furniture and little to no reflective surfaces. If you have a live room or a system that is bright or both I could see how the taming and refinement of the higher frequencies could be immediately appreciated.

 

Let me know if you have any questions about these products I haven’t covered.