Sugden

[simon ess 14]

19 minutes ago, radiant red said:

Did you notice a ‘cleaner’ sound when you got it back? I did it with an A21a (1996 model) 

Interesting. I wasn't sure I was actually hearing that, but yes, crisper, cleaner, sweeter.

[Alvolake 5]

I have always understood that Sugden Class A amps get hotter the less you thrash them, in fact when not working I.e. just being turned on is when they get hotter.  My A21SE has been known to be left on for 2 or 3 days by oversight. Them ‘ eat sinks are there for summat.

[radiant red 5,126]

Transistors are always working with or without a signal so will heat up accordingly. 

[Man in a van 175]

4 hours ago, plasticpenguin said:

Presumably, how quick it heats up will also depend on the efficiency (or lack of with some brands) of the speaker. So if I Totem Arros at 4 ohms and 86db or midrange Dyns my amp would heat up a lot quicker.

Many years ago I used to run Totem Arros on the end of a 21a, sounded mighty fine

Sugden were, at one time, importers and distributers of Totem speakers

I'm actually using the amp today (I bought it in March 2000 )

ronnie

[plasticpenguin 1,770]

2 hours ago, Man in a van said:

Many years ago I used to run Totem Arros on the end of a 21a, sounded mighty fine

Sugden were, at one time, importers and distributers of Totem speakers

I'm actually using the amp today (I bought it in March 2000 )

ronnie

Having demoed Arros a couple of times, they so need a really ballsy amp. No real issues with mine but it does blunt the volume somewhat. I'd rather have the PMCs at 8 ohms and 90 dbs. Not only is it an easier load but better at idling levels. As always with hi-fis it's small margins. 

Edited February 23 by plasticpenguin

[plasticpenguin 1,770]

5 hours ago, radiant red said:

I wouldn’t use either of those speakers as they are not efficient enough. A lot depends on how low a speaker can dip to under load. 
Mine are 6ohm 86dB and I would go no lower although they are efficient in their measurements (apparently) 

This is a different story with Harbeth P3. Yes they can sound lovely on Sugden but they are not that efficient at 83dB. I would not use these long term on the a21a. 
a brand of speaker that is really efficient is Fyne Audio. So at the ‘cheaper’ end of the market, The FS301. Quite a remarkable little speaker 🔊 

Funny you should mention that. When I had the P3s on home demo last year, they were quite tricky to drive. As @Amormusic has PMC 23s, and likes the results, the Sugden should equally give as pleasing results with the TBs. The major fly in the ointment, as I see it, is the potential for the A21 to overheat, given the constant use.

[Amormusic 796]

As per some comments on previous pages the volume dial seems to get super loud, super quick on this.

For my normal listening volume this would be around 730-8am, with it pretty loud by 9am. I wouldn't want to push it to 12midday as this would be way too much.

I've tweaked this with some -10db rothwells, meaning I've now got some play to up to around 10-1030 am for it to become pretty loud.

I've not had such a minimal amount of play on a volume dial before. That would be my only criticism so far.

[radiant red 5,126]

1 hour ago, plasticpenguin said:

Funny you should mention that. When I had the P3s on home demo last year, they were quite tricky to drive. As @Amormusic has PMC 23s, and likes the results, the Sugden should equally give as pleasing results with the TBs. The major fly in the ointment, as I see it, is the potential for the A21 to overheat, given the constant use.

It will not overheat with constant use. It’s designed to run at the temperatures 

[plasticpenguin 1,770]

15 minutes ago, radiant red said:

It will not overheat with constant use. It’s designed to run at the temperatures 

I know you owned a PrimaLuna last year. What's the difference or benefits of the Sugden?

[radiant red 5,126]

27 minutes ago, plasticpenguin said:

I know you owned a PrimaLuna last year. What's the difference or benefits of the Sugden?

No, never owned a primaluna however I have borrowed a pair of monos 10 years ago. Difference? Prima is valve based and Sugden is transistor based. Totally different topology. 
I have yet to hear one of the new Primaluna amps and haven’t heard them with Harbeth so it would be difficult to compare or judge 

[deggie 820]

I think p.penguin means your pathos jon .......

[plasticpenguin 1,770]

1 hour ago, deggie said:

I think p.penguin means your pathos jon .......

Possibly. 

[radiant red 5,126]

7 hours ago, plasticpenguin said:

Possibly. 

Well if it was, the Pathos was a hybrid so class AB with a valve pre amp stage. The Pathos was a wonderful amplifier. Powerful, detailed and able to drive anything. One of the best integrated amps out there. What the A21a does tho is better texture and bass with the Harbeths. If the A21a didn’t exist, I would be quite happy with the Pathos. Like I always say, it isn’t always about price, it’s about synergy 

[calorgas 31]

On 23/02/2021 at 03:58, plasticpenguin said:

Pleased you like the Sugden .

In all seriousness, this is one reason why I could never own a A21 (or any Class A amp). During most of this last year I've had my amp on averaging 7-8 hours every day. Even before the pandemic I used to have it on for 3-4 hours every day. Think the Sugden would have gone up in a puff of smoke long before now.

As I'm typing this, nearly 4am in the morning, the amp has been on since 6pm yesterday. Not only do I play music on vinyl, CDs and radio, but also have it wired up to the Blu-ray, and even watch TV programmes through the amp.

This is a serious consideration IMV for anyone looking at a Class A amp.

Class A amps don't get steadily hotter the longer you have them on, they warm up to 'a temperature' and then remain at pretty much that temperature until you turn them off. I have an A21a and have regularly used it for up to 10 or 12 a day with zero problems or worries. I've been a Sugden owner on and off for 25 years.

Another amp I had been using until recently is a 1980's Marantz PM-4 in (proper) Class A mode - also absolutely fine being left on for as long as I liked. 

I don't know, perhaps there are some Class A amps out there that do have problems dissipating their heat, but as long as a Suggie has some space around it then it'll be fine (in my experience).

Edited February 24 by calorgas

[radiant red 5,126]

Regarding the volume pot. Many amps start at around 8 O’clock such as Rega. This should be taken into account when turning the dial on Sugdens as the alps pot is sensitive and you are so use to a fuller range of the pot on different amps. It’s not a fault, it’s just the way it’s designed. 
The first picture is the starting point on the Sugden and the second is of a typical amp like Rega.

In the view below, at the set volume, you can clearly see what levels are achieved so to listen safely up to say 10 O’clock, you will be at the levels exceeding safe daily levels. Don’t kid yourself, the A21a is quite capable of achieving good decent levels.