Audio Research REF 110 or Ref 75

I have an ARC VT100MK2, and a pair of Wilson Watt Puppy 6.
Considering upgrade and was wondering what I would gain buy either of these amps. I have all ARC pre / CD and transparent cables.
What I would like to gain is a bit more control in the low end. A tighter bass punch if you will. While still maintaing the liquid tube sound in the mids.
I listen mostly to classic rock and jazz at lower volumes ( around 80 db ) sometimes I go louder. I considered a solid state amp, but I do love the sound of tubes.

Thank you
You'll get more power, of course. More importantly, though, it should be cleaner sounding. The VT100 is great, but it does have a bit of an electronic haze in the higher frequencies. Honestly, its not very bad and I didn't even notice it until I put it next to amps like a VAC 30/30 and an Ayre V-5. Other than that, just make sure your preamp is up to the task. If you already have a great amp like your VT100, quite often a new preamp can be a better upgrade.
Thanks, I have a Audio Research LS26 Pre amp. Its not a REF 5 which I one day would like to have. But I assumed my amp being older would be the weakest link.
Are these the correct specifications for your speaker?

Nominal impedance: 4 ohm
Woofers: 2 - 8 inch
Midrange: 1- 7 inch
Tweeter: 1 - 1 inch inverted titanium dome
Sensitivity: 92 dB (1 watt @ 1 meter)
Minimum Amplifier Power 7 watts per Channel
Weight: System Net: 324 lbs
Frequency Response: 21 Hz - 21 kHz (-3dB)
Yes, that is correct
Its a tough choice because both pieces are very good, but there is still room to upgrade. If it were my choice, I would go with a new amp if I thought I didn't have enough power, or some other issue with the amp that you know you don't like. If you have no issues with the amp, a new preamp will usually make a bigger difference. Either way, you should seek more input. I have a lot of experience with your amp, but not so much with your preamp. Given that, I can't make a fair comparison. Overall, you have a very well matched system. Wilson/ARC go very well together if done right. Are you working with a dealer? That would be a big help.

Vdosc, take a look at this Wilson Watt Puppy 6 review. Just above the section titled "Comparison" is a comment from Dave Gordon at Audio Research that talks about using the 8 ohm tap on the amp even though the speaker is 4 ohm. Even if you decide to get a new amp, it appears the speaker/amp combination may be best using the 8 ohm tap.
Zd542, Lak & Vdosc, Would a subwoofer be a possible solution
in this scenario?
I've had watt puppy 7s and Sasha paired with a ref 110 with 6550s and then kt 120s and I too thought it was a great combo but a little light below. The ref 150 made a big difference and I've heard the ref 250s sound even better. My guess is the ref 75 will be an upgrade but a used ref 150 would be a marked upgrade.
Thanks, this is very useful information, and I do have a sub a JL 110 but I prefer to get the most out of the Wilsons. The sub is really too low, just rumble great for Movie but not as tight and punchy as the Wilsons. It does help a little when listening at very low volumes. I can use it as kind of a loudness control.
I have the reference 75 and auditioned it on wilson Duettes, a different speaker I know. I compared it with a Ref 110, upgraded with KT120 tubes and I found the Ref 75 significantly better and certainly powerful enough for the speakers.

When I auditioned the amp, it was on the recommendation of a review in a UK magazine. The reviewer bought the amp himself and commented that 75 to 100 watts has always seemed to be the area that ARC produces great amps. Having heard the ref 110 and 150, I think he is right, the ARC ref 75 seems exceptional, even compared to the 110 and 150.
"07-29-14: Mitch4t
Zd542, Lak & Vdosc, Would a subwoofer be a possible solution
in this scenario?"

In this case, I would say no. The Watt/Puppies can go pretty low all on their own. The real issue is having a 15 watt amp. It should be OK with the mids and highs, but there's no way an amp like that can drive the woofer properly. That also makes it very difficult for the sub. If the sub can pick up where the Puppies leave off when driven properly, that's one thing. That's not the case here. To get the sub working well, it will have to take care of frequencies that Puppy should be dealing with. It shouldn't have to do that. You would have to try it to be sure, but my guess would be that you would hear the sub strain/distort because its working outside its range, or you can let the sub work properly which would almost certainty leave a gap in the lower frequencies that neither speaker is producing. How bad would it be? I can't say for sure because there is a lot of factors involved that you would have to just try it to find out. Also, you would have to figure in the subjective part of the equation. For me personally, the highs have to be just right and I can live with less than perfect bass. It can be the exact opposite for someone else.
Thanks ZD, very informative. I learn new stuff all time here.
I find that integrating a sub for Music with a full range speakers quite difficult. It seems that most of the ones I have heard, do HT very well. And that is their primary market, to shack and rumble the room with sounds of Dinosaurs or explosions all from a small (usually sealed) box with a high wattage power amp built in. And for that they are great. But the Hi-Fi goal is too not only ad bottom extension, but to also ad punch and increase the dynamics or the system. All while not calling attention to itself. For most rock recording this exist in the 50-70 htz and higher range.
Which is difficult I find for these little subs to do without sounding like...a little sub flopping around. Now I have not heard the Wilson Watch Dog sub, it is I am sure very nice, and ported. But it is also very expensive and very heavy!

So my goal is to see what all I can get out the WP6's which sound really really good as is. And BTW since I started this post, I got a pair of Transparent Ultra speakers cables which not only helped the bottom end tighten up, but made everything else sound "right" I was really surprised at how well they work.