If money is no object, then the top-of-the line Miele. But for a lot less money you can get an Asko, Bosch, or KA, all of which do a good job. One thing to consider, the European DWs (Miele, Asko, Bosch) don't have heated dry and require rinse aid to dry the dishes if that matters to you.

We have a Siemens (same as Bosch) and it's very quiet. No dry cycle but no problem as it won't operate without the rinse aid which dries the dishes. But, it doesn't have as much capacity as our old Kenmore, due to more insulation. So, we gave up some capacity for quiet. Rarely do we hear it running.

We have a 7-year-old Asko and I would recommend them. I'm pretty sure ours has heated dry, did they change? We did have the pump replaced under warranty, but I would still buy another Asko (we just bought an Asko washer and dryer).
And it is quiet.

1. They are ALL quiet now, compared to the old clunker you may be living with. Based on your initial query I'll presume you have little awareness of what is out there now.

2. You do not have to worry about noise any more, when you buy a DW that is mid-range or better.

3. Most people signed in here will discuss the fine points of two different kinds of quiet. Between "Quiet Machine 1" and "Quiet Machine 2" there may be a difference, but they are both quiet.

4. I'll take back the blanket statement that all DW's are now quiet, by saying that manufacturers still sell noisy 20th century technology dishwashers at the low end of their range, and if you shop at "low end" stores you'll be shown many of them, although the price may be the same as prices of far better ones at a better store. So, go to a specialized high-end store and look at their dishwashers,,, which will all be quiet, whether they are at the high end of the price range, or only in the middle.

Post again about other requirements.

HTH

Trevor at Eurostoves told me the following.

Historically, Bosch was the quietest, Miele cleaned the best, and Asko was the best for the environment (lowest energy/water). With the new KA at the high-end, the KA now combines the cleaning of Miele and the quietestness of the Bosch.

Personally, I'm looking at lower-end KA (because of budget).

And all the other brands are quiet too. LG, Fagor, Blomberg, etc. Some of them have three layers of different sound insulators. Miele only has one layer.

Our 6 year old asko is very quiet. In fact most people cant tell it is running until it drains water( nothing you can do about that). It cleans very well, uses very little water.

I just checked, it has run 2020 cycles so far :)

"Miele only has one layer"

Not correct!

and there is no comparison with LG, Fagor and especially Bloomberg who didn't even make DW's 10 years ago.

For the most part the ratings are marketing hype. A Euro DW form Bosch , Miele , and Asko are unlikely to be noticed while running by most people.

Yes, a 43dB unit is quieter than a 49dB one , but in the real world most folks can't descerne it. One also has to account for the measurement variants between brands. A 45dB DW from Bosch may or may not be quieter than a 48dB unit from Asko. Really depends on how the measurement was made and the end user is never privy to those parameters.

We purchased an ASKO just recently and love it! It's extremely quiet, has heated dry (with an option to turn it off), and so far our dishes are sparkling! We're constantly amazed at all the options it has, but for us, it's been the right decision. Plus it has a 3 year warranty, which, in this age, is excellent. Good luck with your decision!

Dianne, here is something to consider. How about a 240V dishwasher? Since your having the house built have the GC put an additional 240V, plus the standard 120V, for the dishwasher. Then, you could use the Miele commercial machine that is absolutely fantastic.

Our Bosch (purchased last fall) is pretty quiet and was reasonably priced. The only caveat -- which no one told me! -- is that Bosch's don't dry your dishes. They sort of steam them so they aren't sopping wet, but still damp. It makes the dishwasher more energy efficient, but I find that I need to keep the door open for a few hours to let them air dry. Just a heads up!

simoneb - if you use rinse aid such as Jet Dry your dishes will dry - a friend of mine had the same problem with a Bosch.

I love my Bosch. I find it very interesting that if I run it in the morning, it is still warm in the evening when I get home. The ss inside traps the heat, and forms condensation, which then drips down the sides as the dishes dry....I think this is the theory. Also, I can't imagine any dishwasher being any quieter--I truly can't hear it running. You can lean on it and talk on the phone, and except for the warmth you feel through the counter, you would never know it is on. I'm doing a reno on my kitchen, my d/w door is black--Bosch told me I can order a new door to match my other appliances. You bet I'm doing that and not buying a new one!

Good Luck!