What could be the differences between the Spendor A4 and A7 in terms of sound quality?

I’d think PrimaLuna would sound nice with A series, but haven’t heard it to verify.

FWIW, I use Audio Research DSI200 integrated amp with my D7’s.

I think both the A and D series are not too difficult to drive; pretty easy impedance curves as noted; not extremely high sensitivity ratings but decent.

As you probably know, A series doesn’t come with grills, so the drivers are exposed. I find that the A4 looks kind of strange because the mid-bass driver has a somewhat truncated look (don’t have full circle of material surrounding the driver - like sides are shaved off), almost like the cabinet is not quite wide enough, but that’s just a personal aesthetic appearance thing -- probably some people think that looks cool.

@glow_worm Thanks for clarifying that out lol There seems quite a number of used PL tubes out there and I would love try them out once I make the decision on speakers.

@kren0006 Yes, I noticed the A4s have the woofer edges cut out to have the cabinet shape. I thought it was okay, but seemed a little compromised sound-wise, externally. I’ve just read your posts about the A2, A4, A7, and D7 in other threads btw! Great help.

I assume that it’s just an appearance thing. Can’t imagine that would affect sound. Just looks kinda strange to me. Minor detail 

Agree about the A’s appearance. Vinyl Sound makes grills for $189 I’m considering https://vinylsound.ca/products/splendor-a-grill
Magnets attach to woofer screws, I assume the sound would be unaffected but can’t be sure. 

As a recent A7 owner and exhaustive researcher, I will throw in my 3 cents for both the OP and @glow_worm:

1. I have not heard the A4's but I am not aware of anyone who does not think that the A7 sounds better than the A4. The bass port, larger cabinet, and dampening are the main reasons. That’s an easy binary if cost is not a big issue.

2. D7(.2) is definitely a step up technically. But some don’t like the analytical top end. I am personally tempted to try the D7.2 but early reviews suggest it’s not much different. Even leaner if anything.

3. Tubes go very well with modern Spendors. I am using a 48wpc Line Magnetic LM-805ia and the synergy is amazing. Note that the smaller A4 is less sensitive and on the flip side, while the D7 is a bit more sensitive it has a lower impedance and thus a bit harder to drive.

So if you are concerned about the PL 34 watts the A7’s may be the safest match. That said, tubes might also mitigate the extra sparkle on the D7’s and bring it to perfection. I know there are others who happily run tubes with the D7’s.