Sugden IA-4

I am so happy to hear how satisfied you are with it. I must admit that I'm envious...but in a good way. I'm betting that you'll love the 300b as well, and be surprised at how good the bass is. At least that was my experience with an 8 watt single ended. You're a lucky man!

John

Thanks for sharing my enthusiasm about all this John; listening to anything from Bennie Green to Rosalia to Dj Python to Szymanowski, it just keeps getting better. You were so right about Sugden's quality.
I'll likely start a new thread once my push-pull 300B comes in to share listener impressions.

As a former 0/93 owner ( I moved up to the Super Nines), I would not consider the Pass XA25 due to its high damping factor. The 0/93 bass response in my opinion sounds "unnatural" with amps that have high damping factors. I auditioned am amp that had a damping factor around 250 and it seemed to choke the life out of the bass. I also heard the XA 25 power some Zu Audio speakers ( can't recall which model) and the bass response also sounded way to tight for my tastes. The Sugden amps have low damping factors ( < 25), which is probably why John uses them for solid state amps at shows.

Thanks!! This is a fascinating perspective and I can see the logic in it quite clearly - also a key factor in my usual preference for tube amps. The IA-4 has a damping factor of 45 and its bass is natural and believable with the O93s with good continuity between bass and mid bass. The LTA Ultralinear perhaps had “faster” bass response but I am very satisfied with the organic quality of the Sugden (which has meaningful advantages over that LTA power amp) and am of course curious to see what the Modwright 300B push-pull brings to the table. Nice to rule out the Int-25 as a contender using your sound deduction and experience. I hope you are loving the Super Nines by the way!