What Class A is better? SUGDEN FPA-4 or PASS LABS XA-25

Pass by a mile.

Nelson Pass has been around for decades! Who is SUGDEN? Pass by a mile! (pun intended) :-)

The company was founded by James Edward Sugden in England in 1967, a division of Research Electronics. Research Electronics manufactured scientific instruments and test equipment, designed by James Sugden, for Universities. The A21 was the first amplifier to be put into production and was originally branded for a well known local loudspeaker company called Richard Allan. 
The opinions should be well supported.
I said experiences of the gurus.

I had an all Pass Labs system for 10 years and loved it. I have never heard a product by Sugden, however, by just observing the interior construction of both units, the Pass by mile.
I am not a guru.

https://2.bp.blogspot.com/-gXjwOj25oME/WdaEY45K0uI/AAAAAAACVwY/G6jq0ALxD2MVJlDzTUH3ZU1TghgwtszuACK4BGAYYCw/s640/22196086_1046558578813198_9049732347851855016_n.jpg

mattmiller,

Try enter  www.sugdenaudio.com

Opinions need to be more supported.

I thank you dill a lot.

I have no dog in this fight but that picture of the Sugden amp looked weird to me, no capacitors that I could see. Did some googling and this review:

http://www.hi-fi.com.pl/testy/ko%C5%84c%C3%B3wki-mocy/3465-sugden-masterclass-spa-4

Though in, I think, Russian has what looks like a more accurate internal shot of the SPA-4.

My homebrew Pass F5 is more robustly built than that Sudgen, and so is the XA-25 by a country mile. There’s a ton of stuff that just screams "CHEAP!!!!" to me. A 300VA toroidal is the bare-bones minimum for a 30 watt class A amp. A 400VA center tapped with dual rectifiers would have cost marginally more. What’s more, the power supply filtering is built into the amp boards. They’ve bolted everything to the bottom cover of the chassis rather than install a proper bottom plate. The chassis itself isn’t anything particularly remarkable either. Bottom line: it’s built to a tight budget. That’s an MSRP $1500 amp at best.

I have no dog in this fight , Sudgen sold back in 2013 for $4400

@facten  Thanks for the link I didn't know that site their reviews are really well written and professional. Cheers!

I have heard Pass and Sugden. A friend of mine owns both and prefers the Sugden, unless more power is required. I think they both sound very good, with the Sugden having a bit more clarity and the Pass more bass drive.

Looks like most comments here are from those who have looked pictures of the Sugden amps. Not a great way to determine how they sound IMHO.

Almost bought a Sugden power amp, but decided I needed more power and ended up with an Aesthetix Atlas to match my Calypso preamp.

jperry, 

Thanks a lot.
Your opinion is based in facts, not in supositions.
Thats what I need.
Good, very good. 

@sacresta,

You are welcome. Not sure what speakers you are using, but I heard the Sugden FBA 800 with the Wilson Benesch Vector speaker and it was a fantastic match. Also great with my ProAc Response D-40r

In all reality, they're two completely different topologies. Pass doesn't sell any single ended class A amps anymore. They're all push-pull which is why the XA-25 is a more muscular amp. That Sudgen is clearly a single ended amp. 

Hello jperry,
My speakers are Monitor Audio PL-300.
They sound very detailed and have fantastic soundstage.
Thanks once more.

kosst_amojan
I have no doubt that PASS LAB has fantastic amplifiers.
I understand your opinion, and thanks about it.
My intention was to know the preference of the audiophiles who have listened Sugden and Pass.

As someone mentioned, it's warmer sounding, which is generally expected of a single ended topology. That's not a very common solid state topology. Most turn to tubes for it. It's characterized by a dominant second order distortion harmonic. If that's the sound you're looking for, the Pass Aleph amps or some of the First Watt amps might interest you. 

Hey Sacresta,

I have heard amplifiers from Sugden on many occasions and just reviewed the XA25 for hometheaterreview.com. 

The Sugden amplifiers are quite good in their performance and might compare rather favorably to Pass Labs XA.5 series of amplifiers.  However, the XA25, which does not even use the same circuit design as the XA.8 series is on a much higher level of performance then the Sugden amplifier.  For my tastes the XA25 replaced my XA-60.8 mono blocks in my reference system.  I don't think the Sugden even is on the level of performance of the XA.8 series, therefore it's not even close in my opinion.  For details on the XA25's performance take a look at my review.   

kosst_amojan,

Good ! Thank you for your comment once again. 

teajay,

Thanks a lot. Interesting opinion.

I heard a Sugden a few years ago driving a pair of Harbeths 30.1 and it was a match made in heaven.  I have heard the Pass 30.8 but not the xa25.  The 30.8 is tough to beat if you have the rack room, a strong back and need a large space heater.  The Pass xa25 solves all the negatives I have listed with the .8 series and Teajay's review is more and favorible. Btw I am in the market for a low power amp and the xa25 and the Linear Tube Audio ZOTL40 are my top 2 choices.

Looking at the parts only inside viewpoint, the Pass25 has got the nod over the Sugden.

Bigger trany
More supply capacitance
Multiple smaller PS caps for lower esr
More heatsink fin area, which makes me question the Sugden’s amount of Class-A.

Pass:
http://www.6moons.com/audioreviews2/passlabs3/open.jpg

Sugden:
https://i.pinimg.com/564x/5d/79/d3/5d79d3b2cae87e51ce6b5adc221db1bc--audio.jpg

Cheers George

The question is based on listening!
It is not a project comparison.

designed by James Sugden, for Universities. The A21 was the first amplifier to be put into production

I think you’ll find one that I had was even earlier, the Sugden P51 C51

Cheers George

Sugden P51 C51 pre/power
In case your wondering, 1960's
http://img.canuckaudiomart.com/uploads/large/1792160-sugden-p51-and-c51-combo.jpg

Cheers George