Pass Labs vs. Sugden

I just ordered an A21Se...Sugden is a different approach, first in Class A before Pass, so there's a history there. If Pass made something smaller I would have considered but it's gigantic, gets hotter than Sugden and has a thirst for blood with those giant angular heat sinks. 

I went on pure hearsay of Sugden so I will be sure to report back. But the reviews are really good on the product. 

Please do let me know. I'm genuinely curious.

As am I.  I'm "this close" to  buying a Sugden ANV-50 or IA-4.  The ANV-50 especially looks interesting; I have a relatively small listening room and am hesitant to get a Class a due to heat.  Seems like the ANV-50 would be next best thing.  I'd be using  the Sugden piece with Harbeth M 30.1's.  

I was just looking at the Pass INT 60.  For me, it's just too big and heavy. 

I have the Pass Int-25 and it's a fantastic amp. At 51 lbs. it's no lightweight but I imagine it's infinitely more manageable than the Int-60 or 250. It's no lightweight in price either, especially compared to Sugden. However, this little amp goes way beyond it's conservative power rating and there are demo units regularly available at Reno HiFi. Mine was a demo but essentially new. Something to consider.

Pass Lab's reputation is so legendary, it almost seems like the only Class A game in town. That's why Sugden is so interesting to me.

Clayton Audio is lesser known but makes very highly regarded Class-A amps that you may also want to explore.  There’s also Plinius.  FWIW. 

Pass every day of the week.

Cheers George

I'm a Sugden dealer......They build some flat out awesome gear, and sit at a price point that tends to be a bit less than Pass.

Pass is for sure nice stuff, but the Sugden sound is quite amazing.  Build quality is also very good.  

There's a reason Sugden has been in business for over 50 years now!

Belles makes a great class A amp
(SA30)

Belles has been on my radar for a while. Sugden does have a great reputation in England for sure.

@georgehifi I always enjoy and learn from your posts. Have you done any comparisons between Pass and the others (Sugden, Belles, Clayton) that puts it first and foremost for you? 

This topic was discussed in another thread, albeit with a twist, but it is still the same question:

https://forum.audiogon.com/discussions/what-class-a-is-better-sugden-fpa-4-or-pass-labs-xa-25/post?p...

A friend came over and brought his Pass Int-60 to try in my system, which was no easy task. I had been using tube integrateds from Cary, Rogue, BAT.  And at the time I had a Primaluna.  We had the Pass plugged in for about an hour before the units were switched .  It was an OMG moment.  The sound stage was wider, the music filled the room, bass was full and controlled.  Unfortunately the amp is to large and did not fit my current layout.  After that I started looking into Class A integrated amps and ended up with a new Sugden A21se Sig. Do not discount the Sugden.  For me it is just a satisfying as the Pass. Its just that the English took a little different path to get there. 
 

@georgehifi I always enjoy and learn from your posts. Have you done any comparisons between Pass and the others (Sugden, Belles, Clayton) that puts it first and foremost for you?

No A/B’s, but just looking at the internals, the Sugden looks to me like it could be a "anaemic" version of Pass amps, look at the transformer size, amount of output transistors and power supply capacitors.
https://cdn.shopify.com/s/files/1/0212/2502/products/A21SE-INTERNAL-1-WS_large.jpeg?v=1496938402 lots of empty space.

There’s also a reason they are saying the Pass get’s hotter, even though it’s bigger heavier and got more heatsinking, it’s most probably because it has more "music making" Class-A bias than the Sugden.

Cheers George

Sugden is not anaemic at all.  I've had quite a few customers do a direct comparison to PASS and pick Sugden.

In the end, both are great brands.

Sugden is not anaemic at all.

Read again, not the sound, what’s inside!
Even on Sugdens "biggest power amp", from 2006 the transformer and very thing is "anaemic" in comparison inside
https://neophonics.com/wp-content/uploads/2009/07/SUGDEN-MASTERCLASS-SPA-4-STEREO-AMP_1709N-INTERNAL...

Compare that to Pass https://youtu.be/Ytqk_9z0KMQ

Sugdens could be nice sounding amps for small 2 way to medium size systems for unit dwellers, even bedroom systems. They are not in the same "bruiser" league as Pass Labs stuff.

Cheers George

Sorry, but not true at all.....I have no trouble driving larger speakers in my demo area with the several of the Sugden options.

Now if you are trying to say that PASS offers some amps that have more power, then you would be absolutely correct.  Sugden has never played in the high power Class A/B arena, and I doubt they ever will.  

FYI...the SPA4 is not Sugden's largest amp.  And it retails at $6k in the US.  I do believe that the Pass in your link is somewhere in the $15k-$16k range.  

Look as a guy that's built many high bias Class-A amps, even a couple of water cooled ones, what I see is what I see.
And Pass is way ahead of Sudgen for an amp for any "driving condition", and above that again by the same measure is to me is Gryphon.

Cheers George

@goldprintaudio  
Is there a Sugden amp or integrated you’d recommend for a Klipsch Heritage line speaker like the Forte III?

@t_ramey 
I would look at the IA4 or ANV-50 on the integrated side (maybe even the A21SE).  

I have the A21se sig. and have driven Klipsch RP600m speakers , as well as JMR Bliss Silvers, Rogers LS3/5a and Vandy Treo CT’s.  It has produced rich, deep, holographic sound with all of them.  I don’t think you can go wrong with Sugden.  

Interesting.  Sugden A21se Signature: 30W into 8, 40W into 4.
Vandersteen Treo CT: sensitivity 85dB; nominal 6 ohms.

Yes, with the Treo makes one wonder about the size of the room. 

Resurrecting an older thread, but wanted to weigh in...
I've had a Sugden ANV-50 for about 1.5 yrs. It is fed by respectable upstream digital and analog sources and cabling, and delivers output to relatively inefficient (83dbW, 10 ohms) downstream speakers. It is spec'd at 50W/ch into 8 ohms.

In a few words, I am continuously blown away by the soundstage, clarity, speed, and holographic presentation that the ANV-50 serves up on many, many albums and hi-res FLACs. Even with the severely inefficient speakers, I get usable, high quality volume all the way up to 12 o'clock on the dial.
However, there are a few things that I'm not 100% enthusiastic about. First, and most importantly, the sound does compress a bit and lose some dynamics as that volume knob gets closer to 12 o'clock. Perhaps that's when it's switching to more A/B bias or something, but you can hear it kind of run out of gas in the upper power range. In fairness, I play my music loud in a very large room with bookshelf speakers. I'm asking a lot from the Sugden. If you really need to lean on it for power delivery with very inefficient speakers, you may want to look elsewhere.

Second, there's a feel to the volume knob that feels cheap. It works fine, no issues mechanically, but it feels "plasticy" to the touch, and seems like it won't age well as an heirloom piece.
Third, and not that big of a deal at all, the current volume indicator on the dial is incredibly difficult to see from 10-12 ft away. I had to put a piece of black tape on it so I could see the volume knob rotate when using the remote. Speaking of the remote, it's super cheap, plastic, and lightweight, and the volume up/down labels are already wearing completely off after 1.5 years. But, it works.
I just upgraded my phono stage to an Allnic H-5500, and holy cow... The Sugden ANV-50 throws an incredible, holographic soundstage!  All the detail, inner detail, speed, and clarity that you could ever want - unless you have to really crank it, when it will start to compress.
The Pass INT-60, Luxman L-509X, and Allnic T-2000 30th Anniv. are all on my short list for potential upgrades, but I am extremely happy with my ANV-50 right now. It's allowing me the time to upgrade all of my sources and cabling, get my power supply cleaned up, and really appreciate and enjoy each and every upgrade that I've introduced so far. I've never felt that the ANV-50 was holding me back, but there will come a day when I need to replace it with something that won't compress at very high volume.
Hope that helps some. I auditioned the Sugden A21SE but not the IA-4 prior to purchasing the ANV-50. The ANV-50 was much better than the A21SE in my system, but couldn't begin to tell you how it compares to the IA-4 or Pass gear.

Anyone in the Denver area with a Sugden, please message me. I have a fun idea. I’ll provide the beer. 

@georgehifi Have you even bothered to listen to a Sugden? I'd say you would eat your words. Sugden was THE FIRST Class A solid state way back in 1967! I think they know how to build a Class A amp.....I own the Sugden A21se and it is spectacular. 

I have both Sugden iA4 and Pass Labs Int25. Comparing the sound quality, IMO neither is much better than the other. The Sugden is of better value due to higher wattage and lower price than the Pass Labs.

@jamesmartin17 Interesting. I want @decooney  to see that comment.

@jamesmartin17 @hilde45 ah, thanks for sharing that comment. While I’ve been a fan of both only reading, never had the chance to compare both side-by-side.

Whatever sounds more vintage, less modern, all transistory and stuff is the one I’d pick just so I could go play some poor old ’70s recordings on it, just because. Slather it up with some overly copper interconnects too while I'm at it! 🤣

IMO, another advantage of Sugden over Pass Labs is the faster warm up time of the Sugden.  It takes the Sugden around 20 minutes versus Pass Labs of about an hour.

Note the head-to-head You Tube video by Harley Lovegrove on the Sugden A21SE vs. the Pass INT-25. Lovegrove discusses the pros and cons of both and ends up slightly preferring the Sugden for half the price.