Review: Grand Prix Audio Monaco Amplifier Isolation System Stand

Category: Accessories

I had been using solid state monoblocks that I had put on Michael Green stands. When I bought a Sonic Frontiers Power 2 it was too large to fit on one of the stands without hanging over the side. So I decided to get a new amp stand. I was looking at Zoethecus because they matched my bookshelves. I was at Experience Audio here in Seattle and was looking at the Grand Prix stand. I thought it was very cool looking, (even though it didn't match my bookshelves). I researched and researched and finally one day just wanted to buy something to get my Power 2 off the other rack. Experience Audion owner Tim had extolled the virtues of the GPA racks before and I had read enough to know that this was fine equipment. So I went in and bought one though it was way over the budget I'd set. It was one of those purchases that seemed NECESSARY. Tim seemed subdued about the sale but I didn't think anything of it. I went home and did a little comparative listening with the other rack then set up the Monaco. After turning on the amp and putting on some music it took approximately one minute to tell the difference. WOW! I could hardly believe it as I kept listening. I called Tim back to see if he was still at the store after hours and he was. "What the @*&# is going on!" was all I could think of to say. He laughed and told me "I figured I'd let you see for yourself rather than build the stand up. I've told you before that these are great racks."
I've used a lot of tweaks over the years and this blew the power cords, the cones of various shapes and sizes, the weights on top, the shelves and bladders below right out of the water. Okay, that's hyperbole, but still. I was reminded of the time that I tried out my first high-end interconnect, some Audioquest Lapis that a customer at the record store had lent me. My roommate and I went home and we were listening very hard, very intently to the music through my Kimber PBJ's. We figured the difference was going to be subtle so imagine two record geeks, hands on their chins tilted forward toward the speakers. When I put the Lapis in the system we were both blown backwards. Wow! That rocked! With the GPA amp stand, I felt the same way. I hate to use the cliches but it was like the noise floor dropped to the apartment below me, music seemed fuller, rounder and coming out of a silent background. I figured the stand would make a difference but I wasn't expecting this. The interesting thing was that instead of the usual, "there was more detail" or "the bass was improved" I didn't notice either. What I noticed was a more natural presentation of the music that made it sound whole,organic, Instead of concentrating on the qualities I was hearing the gestalt of the sounds. For once I was just enjoying the music without being "audio-critical" of what I was hearing.

This is a brilliant piece of equipment. I would think this is as essential as any upgrade you could make. Its aesthetics are wonderful, this is one great looking stand, it would make a clock radio look good just for sitting on it. But of course, buy it for what it will bring out of your amp.

The only way you will get my GPA amp stand away from me is if you pry it from my cold, dead fingers, or offer me more money than I paid for it.

Associated gear
Sonic Frontiers Power 2
Pass Labs X1 pre
Golden Tube Audio Pre
Sonic Frontiers Phono Stage
Oracle Turntable
Micromega CD Players
BMI/Nordost/Synergistic Research cabling and Audiomagic conditioning

Similar products
Micheal Green Basik Rack
Target Stands
Nice review. I felt exactly the same way as you when I first got mine. These amp stands under my Audiopax mono amps literally took my system to another level. Sit back and enjoy, and when you are looking for a little more try out the Apex feet that go under the amp stand, I'm sure they can loan you a pair from the stereo shop. The Apex feet made nearly just as much improvment as the stand itself did.
I felt the same effect with the amp stands, but will I get the same thing with the Monaco 3 shelf rack for a DAC and transport? has anybody felt the same improvement with the source as we have with the amps?
I bought a Le Mans 5 shelf for my other system after hearing the effects of the amp stands, and while not quite the impact the amp stands had, I would still call it a major improvement.
It all started with a blown 300B output tube on my VAC 140 Renaissance monoblocks. The tube was from KR, and at that time they had discontinued making the 300B tube in favor of a similar one with greater output, but not suitable in my amps. A similar thing had happened 6 months before, and I was able to find a matched pair online. No such luck this time, despite very gracious cooperation from madame Kron herself.
Next step was to check in with Kevin Hayes of VAC. Time to bite the bullet and retube the monoblocks, which requires 4 pairs of 300Bs per channel. Kevin suggested a Chinese tube relabeled by VAC as the best choice. OK, I ordered a set of 16 of these tubes. But not before checking in with Andy at Vintage Tube Services. Andy has done a great job of re-tubing my TRL pre-amp and the low voltage tubes on the VAC with NOS selections. His vehement response is that there is NO good Chinese tube made. Keep looking for more KRs or go with the Western Electrics, or anything but the Chinese. Not the first time that 2 audio experts have disagreed.
Well, since I had already tried with no success to scare up some KRs, and didn’t want to pay the astronomical price for Western Electrics, which have some down-sides other than price, I elected to take up Kevin Hayes on his offer of the VAC labeled Chinese tubes.
My impression was: These are terrible. Lots of detail was lost compared to the KRs. Musical passages that display great separation of the instruments were now all mushed together. Way too laid-back a presentation. I never would have bought those amps if they came tubed like this. I called up Kevin and shared my disappointment.
He was very surprised, and offered several helpful suggestions, including that I should examine any part of the system that had been changed at the time I re-tubed with the KRs.
On searching my long-term memory, I found that I had at about that same time switched from Stand Design racks to huge heavy slabs of sandstone obtained from the local quarry and separated by sandstone blocks. At the time, going to sandstone had made a big overall improvement in the sound of my system. Could it be that this type of 300B tube was incompatible with my racks?
I began to do rack research. An audiophile friend with ears that I trust had purchased a few years back racks from Mapleshade. I called them up and got for experimental purposes a few sets of the large brass footers to put under the amps. These sounded terrible compared to the Marigo footers that I replaced to try the brass footers. No big surprise. Mapleshade claims that the brass and maple planks have to be used together. I tried using some maple boards left over from a construction project, placing these between the brass footers and the sandstone slabs. This arrangement sounded considerably better than the Marigo footers, and made me think that going this direction could result in me even liking the new 300B tubes.
I called up my friend to see if he was still enjoying his Mapleshade racks after having them over a year. His answer was that there is probably a better way to go. He had been keeping the wood, but replacing the brass footers with ones from other companies, having concluded that the brass was “non-musical”.
Which footers did he like? He reminded me of an experiment that we had done at my house. He had brought a set of Apex footers from Grand Prix Audio, and we replaced my doubled Symposium rollerblocks under my Sony SCD-1 player with the Apex. The result was a stunning improvement. More detail, reduced shrillness of higher frequencies on certain poorly recorded music. Overall, less fatiguing to listen. I was very impressed. However, I had just bought a set of tuning dots from Marigo to treat the Sony. This involves sticking very tiny vibration-dampening dots on every capacitor and voltage regulator in the unit. This brought about the same degree and type of improvement that I heard with the Grand Prix Apex footers. I didn’t even know that Grand Prix made any other product, and chalked that one up to a big win for the concept of resonance control, regardless of whether it is accomplished internally or externally.
He informed me that Grand Prix’s main products are their racks, and that I should really consider them for my system.
So, I called up Alvin Lloyd at Grand Prix, who told me that the Apex footers do only a fraction of what racks can do, and that most customers who buy their racks end up no longer bothering with footers and other tweaks. He was very helpful and informative, explaining just why the sandstone racking was not doing what I had intended, and indeed could be responsible for the poisonous effects I was noticing. I ended up buying 2 Monaco racks, placing my power amps, pre-amp, CD player and DVD player on them. Power conditioners, headphone amp, and satellite receiver were left to fend for themselves on the floor.
It took a bit of time to set up the racks, getting them level, applying the proper damping material to fit the weight of each component on the appropriate shelf, and audition the equipment as is, and with upgrades of apex footers, harder support balls for the footers, adding lead shot to frames of racks.
The resultant change in the sound of my system was at least as dramatic if not more dramatic than any other single equipment upgrade I have ever done. Much more detail, better staging of instruments, reduction of irritation on harsh-sounding recordings, better base. In other words, I was instantly hearing much more of the music. There was no trade-off of setting the presentation forward with high-end harshness that often masquerades as increased detail. I started to re-listen to all of my favorite music all over again.
Now was the time for some experimentation. I replaced most of my new Chinese 300B tubes with the KRs. I could do this with 7 of the 8 pairs. The KRs just did not sound as good. I apparently had been using the KRs as a tone control to compensate for the deadening effect of the sandstone racks. I replaced the KRs with the Chinese VAC tubes, and breathed a sigh of relief. Kevin Hayes was right.
Ok, did this mean that the Grand Prix Monaco racks were just a different type of tone control that happens to fit my system better. I think not. The reason that I think not, is that I now had a setup with much greater resolution. I was hearing more of the music, and could instantly tell the effects of whatever changes I made in my set-up. This is greater resolution and truth, not a tone control.
Next, I tried re-introducing various footers under the power amps. Tried big brass things from Mapleshade, Symposium rollerblocks, Cardas myrtlewood cuboids, Marigo footers. The result was that all of these things changed the sound, but none for the better. The Marigo footers came closest to not worsening the sound very much of all of the footers tried. The amps are now sitting on the naked shelves, and sound best that way.
I tried the same thing on all of the other racked components. Only the CD player improved from the placement of Marigo footers under it. Interestingly, these footers did not do well under that player when on sandstone, and the Symposium rollerblocks had improved things a lot. On the Monacos, the Symposium blocks had a distinct deadening effect on the sound.
As a side-note, I have recently replaced my Sony SCD1 because the transport developed an un-fixable tendency to not play most discs. The replacement is a Marantz SA14 modded by TRL. Sounds much better than the Sony, and sounds much better naked on the rack with no footers.
I have not tried any of the available upgrades from Grand Prix, such as replacing the Lucite shelves with the Formula shelves, or putting Apex footers under individual components. Maybe later. I did get Apex footers for under my speakers (Avalon Eidolons), which sound much better than the spikes supplied by Avalon or the big brass things from Mapleshade. In the future, I may do some of these upgrades, but I can hardly conceive of ever replacing these racks, no matter what component upgrades I ever do. This means that the Grand Prix rack is the only component that I expect never to replace.

Equipment in my system:

Marantz SA14 CD player modded by TRL
Sony SE9000 DVD player
TRL pre-amp
VAC Renaissance 140 monoblocks, mk III
BPT signature power conditioners
Marigo signature power cords
Cardas Golden Cross interconnects
Cardas Neutral Reference speaker cables
Window glass treated with Marigo Super-dots

A sad P.S.

About 2 weeks after getting the Monaco racks, I treated all cables and tube pins with the Silver contact enhancer from Mapleshade. This made a very nice improvement in resolution, which I really enjoyed for a few months. Then trouble began. The sound started to get muddy. With time it got worse and worse. I tried troubleshooting with tube swapping, and came to the maddening observation that if I would switch around the tube locations in the pre-amp to figure out which tube was going bad, the sound would clean up and lose the mud for a few days. Sometimes, operating the volume control on the pre-amp would cause a crackling sound. Flummoxed, I called up Paul at Tube Research Labs, explained the problem, and he had me return the pre-amp for repair.
It turns out that there was no problem with the pre-amp at all. The problem was the contact enhancer. According to Paul, this type of contact enhancer tends to lose its conductive properties with time and heat exposure, and become an insulator. The solution was to clean this stuff off everything, a job that took 6 hours of scrubbing off the material using white gas. I then replaced it with the QuickSilver contact enhancer from XtreveAV, which Paul has found to be reliable and to not become an insulator with time.
The happy result: the mud is all gone, and I am back to listening to music with glee rather than consternation.