To upgrade from simaudio 3.3i to 600i or not?

Volume-wise you won't get much more out of the 700i; the difference is from 125W/channel (600i) to 175W/channel (700i). And of course ecah time you double the watts it produces only a 3db increase. With only a difference of 50 watts/channel between the two models, the volume difference will less than a 1.5db increase.

The difference in sound quality, then, should be the main factor that determines whether you fork out another 4 grand or not. And sorry, although I've heard both the 600i and 700i (with focal 1028 BE / siltec 770 series / moon 750D), I haven't compared the two amps side by side.

I have, however, compared the Moon 330i next to the 700i. I say this only to point out that perhaps you are better off investing in two LessLoss DFPC Signatures to power your source and 600i. Why? Because I found that the performance enhancement offered by the LessLoss DFPC Signatures was clearly greater than the performance enhancement offered from upgrading from the 330i to the 700i. Not to mention, two Signatures would cost around $2100 (shipped from the EU), almost half of what it would cost you to bump up to the 700i. If you don't own LessLoss DFPCs already, I expect you'll be surprised how much just two such power cords will improve your system.

I so agree with the prev message.Unless you can notice an improvement in sound quality its probably not worth the upgrade. Changes in cables/isolation can demonstrate sig improvements. I am running Nordost cables-mostly Valhalla which I love but pricey. I have a couple of Nordost Tyr left to upgrade since I moved from a moon 5.3 phonstage to an Allnic H-3000 tubed phono. I have tried a lot of cables at home in my system (thanks to a few great dealers) and really like the Nordost product. Some great deals on AudiogoN. If you can go for the Tyr but also the Heimdall line is regarded as great peformance to price. Also like the Crystal Cable line, Analysis Plus and Accoustic Zen product. In terms of importance of cabling the power cord is most important followed by interconnect and speaker cable. A friend who distributes the Allnic product gave me a new interconnect cable to try (High Fidelity Cables 1500.00 1 meter). Have not tried as yet because I picked up a used Allnic L-3000 tubed preamp for my system and wanted to get a sense of that prior to playing with a cable change. Reports have been extremely positive and supposedly Harry Pearson of ausio fame has used in his reference system and was blown away. He has been a Nordost Valhalla fan.

Thanks to the both of you. I appreciate the sound advice. So, what i hear from the both of you is to spend my money on cables. This sounds like a great idea. I would like to maximize what i have. I am taking the advice from Robert Harley and not spend more than 15% on cables. I just seeked a consult from usedcables.com and they suggested Audience cables. Not sure if they have an abundance of these cables or they are really that good. In adittion, i did just check out the website on lessloss. Not really sure what to think of it without listening to it. Fossda, i see you switched to a tube phonostage. Perhaps a stupid question, but with getting a tubed phonostage give you that warm tube sound if you are running a solid state amp?

Harris4crna. I don't know how much 15% of your budget is, but 15% or not you owe it to yourself to order and listen to the LessLoss DFPC Signatures (one for your source, and one for your moon 600i). I've had the Signatures on the moon 700i and 750D (at the same time). It's a little scary how much the sound improves. You simply can't go wrong.

Thank you for the suggestion. Will look into it. Sounds like I will upgrade with cables first and perhaps later on check into other toys such as a JL Audio Sub. These Cremonas just seem not to punch out the base when playing Rock like I wish. You would think such an expensive amp and speakers would have a fuller range. We will see.