Suggested Improvements for Set Up?

Looking for advice to improve my current set up, which is as follows:

Polk LSIM 707 (Left and Right)

Polk LSIM 706C (center)

Polk DSW MicroPro 3000 (sub)

Yamaha RX-A3020

Apple TV

Panasonic VT50

What would I get greater improvement from a DAC or separate power amp?

Set up:

Fronts are currently approx. 8 feet apart with 22 degree toe in

Sub is located between left and media cabinet

Center is on top of media cabinet

Any suggestions...
I think if you went with a good Pre amp/amp combo like Primaluna or Rouge Audio or Vincent Audio (there too many to list) ...the results could be a life changing event.Other than that,Spend the money on a good Oppo universal machine.This machine could be all you need for videos,streaming,Blue rays,Sacd,cd, playback.

Matt M TX
hi, my system [2 ch] changed for the better with 2 subs. i don't think i could go back to one sub. but it is complicated and you didn't state your goals or budget. possibly some polk owner could relate how seperate high power amps changed his system performance. good luck.
"What would I get greater improvement from a DAC or separate power amp?"

Definitely the amp. Your system isn't revealing enough to get the full benefits of what a new DAC will do for your system. I would leave it for last.
I think it depends somewhat on the type of amp you're considering. Based on my similar situation, my DAC made a bigger improvement for me. I had a Marantz receiver driving Sonus Faber Liuto monitors. I bought a separate Emotiva power amp and used the Marantz as the preamp. There was a slight improvement, but not what I was hoping for. I think using a receiver as a preamp can limit the benefits of a separate power amp. However, you're Yamaha is newer and a better model than my Marantz, so it's possible you could get more out of it as a preamp than I did in my system.

I sold the Emotiva, and bought an Arcam rDAC, which made a much bigger difference. And that's an entry level DAC for under $500.

Recently, I decided to get my Marantz completely out of the two-channel chain. I bought a Krell S300i integrated amp, and that's made a huge difference. I only use my receiver for movies now, with the Krell doing it all with music.

I assume you are playing lossless files through AppleTV? If you're still using MP3's, moving to lossless files would be a great way to improve sound quality.
The 707s need a lot of power to perform at their best and that will require a separate power amp. Though rated at 150 watts per channel all the channels are drawing off the same power supply. A similarly rated (or more) external power amp will definitely improve the 707s performance.
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Although i do not know about your speakers... over the years this is my experience with upgrades to home theater.

in order from most noticeable in real life listening.

1 Get the best and biggest center channel that MATCHES your two front2 speakers.

2. make the room you are using light controlled.... add blinds and or drapes. you want the " experience" of the theater, it needs to be dark.

3. if you do not have a dedicated home theater, or if you do... keep the echo down.... use thick carpets and drapes.

4. Subwoofer... i did not believe this was all that big of a deal.... for years a had an old 15" vega... once i found a used "higher end" sub, there was a difference worth mentioning.

5. separate amp... it does not have to be thousands and thousands of dollars. look for an amp that 1.... goes down to the ohms that your speakers might dip to (this is not as important. if you are crossing over you speakers to a sub) 2.. an amp that gets as close to doubling for every drop in ohms... example 8 ohm @200 watts to 4 ohm @400 watts to 2 ohms at 800 watts. get an amp with a lower THD. beyond that dont spend too much money, it would be hard to REALLY hear a difference.

6. dial in your system... make sure your tv setting are correct for your environment, speakers are placed not right against the walls, just a good thicker speaker cable, adjust the room correction that you might have and make sure the room correction didn't mess up a setting.....etc

These are the suggestions that I would tell my family and friends.

i am looking into acoustic panels... we will see (or hear) if this makes a difference.

also... the smallest difference that i have found was changing over from a good receiver ( with pre-outs for an amp) to a new higher end processor only)

hope this helps,
I just wanted to update everyone on an amazing upgrade to my system. I just added the new Emotiva XPA-2 Gen Amp to my set up. Wow this amp really made the 707's come alive! The difference in sound between the XPA-2 Gen 2 and RX A3020 is remarkable. The 707's produce so much more detail and bass now that they are appropriately powered. Made me fall in love with the speakers again! Thanks for your help!
In the low-cost / high-impact category, even though it wasn't on topic - take a look at the room. I've done some minimal, visually non-intrusive treatment that tamed some high-end harshness and really opened up the music.

Congrats on the amp and the improvement - now take a quick look at the room to really bring out the last bit of detail and control your amp/speaker is capable of.
I was going to suggest the amp. I have the earlier AVR, the 3010. I used that and an old Yamaha amp at 150wpc to drive my speakers. I switched between them and didn't really hear much difference. Through a recommendation from a 'goner, I upgraded my amp - to a used one from here, different member though. Unbelievable difference!!! The quantity and quality of bass means I don't use my sub for 2 channel, and the imaging and details improved greatly. My room isn't 'tuned' or treated and is very live, but I can totally relate to the improvement you noticed. I bet I put off the upgrade-speakers bug for at least 6 months:) I have lots of work ahead of me to get the most out of what I have, and there will be upgrades, but that one change was huge for me.
Beaverlake, what sort of room changes have you done? My room needs work, but since it's the family room as well, I don't have a free license to do anything.