Sugden a21se

[Jay73]

Hello,

I just acquired this Amp.

I had a question about the speaker binding posts.

Seems like you can screw/unscrew the binding posts.

Is that so that different sizes of banana plugs can be used?

At first, it seemed like I couldn't plug in my AudioQuest Type 4 Banana Speaker Cables but after slightly turning the binding posts, I was able to push in the speaker cables.

I just want to make sure I am doing it correctly.

The sound seems fine to me, I am assuming I did it correctly.

Would appreciate any feedback.

Will be playing with this amp this weekend to see what it's all about.

Thanks

 

[MrHifiTunes]

Hello,

I just acquired this Amp.

I had a question about the speaker binding posts.

Seems like you can screw/unscrew the binding posts.

Is that so that different sizes of banana plugs can be used?

At first, it seemed like I couldn't plug in my AudioQuest Type 4 Banana Speaker Cables but after slightly turning the binding posts, I was able to push in the speaker cables.

I just want to make sure I am doing it correctly.

The sound seems fine to me, I am assuming I did it correctly.

Would appreciate any feedback.

Will be playing with this amp this weekend to see what it's all about.

Thanks

you need to open the binding posts so you can plug in your banana plugs. When the cables are attatched you can lock them in.

 

[Cooper]

Newbie here, considering the A21SE to use with 4 ohm 85db sensitivity Dynaudio Heritage Special bookshelves. If anyone here has heard or is doing this combination, what do you think of this pairing, how would you describe the presentation particularly at lower volume?

 

[mocenigo]

Newbie here, considering the A21SE to use with 4 ohm 85db sensitivity Dynaudio Heritage Special bookshelves. If anyone here has heard or is doing this combination, what do you think of this pairing, how would you describe the presentation particularly at lower volume?

I believe the A21 is underpowered for those speakers. The result would be clipping or distortion (which is already audible in that product at normal listening levels). The design of that amplifier is quite outdated, it is about 60 years old and has had not minor updates, mostly in the area of “component quality” instead of circuitry (where it would have a bigger impact).

 

[Cooper]

It's a brand i've only recently become aware of. Will follow this thread to see if anyone else shares a thought on this pairing.

 

[MrHifiTunes]

Fault statement. The design has many improvements over the years. Even from outside the company. Specially in the A21SE signature. Improved pre amp section and improved power section.
Class A like this one may not offer the beste measurements, but if you look closer, it is only second order distortion. 3th order is under threshold.
The amp is very musical and nice sounding. Not to warm like a tube not too analytic like class AB / D.
Fore just the right balance to have a sound you can listen too all day long.
Class A is also preferred when listing at low levels. Distortion is lower at low levels for class A design.
The A21SE signature is also very powerful. Before I had a Arcam alpha 10 (100w /8 ohm. 800w/25A power supply) but the sugden sounds better. Maybe something to do with the instand power of Class A?
What I don't like is the high input sensitivity.

 

[MrHifiTunes]

Here some measurement @10khz.
Second harmonic <0.02%. 3th almost vanished in the noise floor.

There is some video on YouTube from pearl acoustics who made a comparison between the A21 SE and the pass labs int-25.

 

[DavidEdwinAston]

I have had this model Sugden in my garage for some years. Purchased for coppers, out of daftness I suppose.

I did email the company about the possibility of getting it working, and they weren't interested. Naturally, my own interest was diminished by their lack of enthusiasm. So it sits there!!! I imagine a small boutique company has purchased the name, and possibly gets by on it.

 

[Cooper]

I believe the A21 is underpowered for those speakers. The result would be clipping or distortion (which is already audible in that product at normal listening levels). The design of that amplifier is quite outdated, it is about 60 years old and has had not minor updates, mostly in the area of “component quality” instead of circuitry (where it would have a bigger impact).

Have been listening to the Heritage Special with the A21SE for a week now and not underpowered, drives the speakers quite nicely.

 

[mocenigo]

Have been listening to the Heritage Special with the A21SE for a week now and not underpowered, drives the speakers quite nicely.

As long as you are happy, we are all happy!

 

[mocenigo]

Here some measurement @10khz.
Second harmonic <0.02%. 3th almost vanished in the noise floor.

There is some video on YouTube from pearl acoustics who made a comparison between the A21 SE and the pass labs int-25.

Thank you but distortion at 10Khz is nearly useless, as the 2nd and 3rd harmonics are 20khz and 30khz which are inaudible. Even if you can hear 20khz, it would be so attenuated that even 10% distortion would be inaudible.

There is a reason this is sometimes measured at 1khz. It is dead center in the range where our hearing is most sensitive. It is also unlikely that equipment with, say, -100db distortion at 1khz will have -60db at 2 or 3khz or 500hz. Of course this may happen.

Also, which power? (Not that it is relevant for a measurement with a 10Khz fundamental.)

 

[MrHifiTunes]

Thank you but distortion at 10Khz is nearly useless, as the 2nd and 3rd harmonics are 20khz and 30khz which are inaudible. Even if you can hear 20khz, it would be so attenuated that even 10% distortion would be inaudible.

There is a reason this is sometimes measured at 1khz. It is dead center in the range where our hearing is most sensitive. It is also unlikely that equipment with, say, -100db distortion at 1khz will have -60db at 2 or 3khz or 500hz. Of course this may happen.

Also, which power? (Not that it is relevant for a measurement with a 10Khz fundamental.)

I couldn't find other measurements.
I would not say that distortion measurement at 10khz is useless.
At 10khz distortion is worse then at 1khz. So you know that the distortion at 1khz is even lower.

Actually for most amplifiers the distortion rises rapedly after 1-3khz

Distortion In Power Amplifiers

 

[MrHifiTunes]

Have been listening to the Heritage Special with the A21SE for a week now and not underpowered, drives the speakers quite nicely.

I don't think you need more power for domestic use with not too low impedance speakers(<3ohm)

 

[mocenigo]

I couldn't find other measurements.
I would not say that distortion measurement at 10khz is useless.
At 10khz distortion is worse then at 1khz. So you know that the distortion at 1khz is even lower.

True. "nearly useless" was perhaps a bit too much, but still not extremely representative.
Esp since we do not know the voltage. This is a circuit that has been often given at 10% or 25% at the max nominal power.

Actually for most amplifiers the distortion rises rapedly after 1-3khz

Distortion In Power Amplifiers

Indeed I said that -100db at 1khz does not imply -60db at 3kz, I did not say -82Db.

 

[mocenigo]

Fault statement. The design has many improvements over the years.

I know of the upgrade from the first to the second series. Then they changed lines completely and only much later they improved the power supply and output devices to resurrect the design as the Signature series with more power, and the SE version has a better preamp part. (By the way, today we know very well how to design perfect preamp stages and buffers, today, ask Tom Christensen or Frédéric Jacquot, for instance.)

Even from outside the company. Specially in the A21SE signature. Improved pre amp section and improved power section.
Class A like this one may not offer the beste measurements, but if you look closer, it is only second order distortion. 3th order is under threshold.

I know,

The amp is very musical and nice sounding. Not to warm like a tube not too analytic like class AB / D.

I never understood what "musical" means in elecronic equipment.
But I know that amp, and it sounded a bit warm and glowy. Not too much. Overall, the setup I heard was very, very pleasing, but I preferred an amplifier by Norma. Much cleaner and in my opinion more transparent. FWIW, since this is all subjective.

OTOH I do not consider my class D amp (Purifi build) "too analytic" – I get the (purely subjective) feeling that it is rendering what was recorded, without adulteration...

Fore just the right balance to have a sound you can listen too all day long.
Class A is also preferred when listing at low levels. Distortion is lower at low levels for class A design.
The A21SE signature is also very powerful. Before I had a Arcam alpha 10 (100w /8 ohm. 800w/25A power supply) but the sugden sounds better. Maybe something to do with the instand power of Class A?
What I don't like is the high input sensitivity.

The high input sensitivity is a problem with modern sources, but nothing that cannot be solved with an inline attenuator.

 

[Ze Frog]

Alternative for this kind of amplifier is NVA, worth checking out their site, all boutique, made in Britain.

 

[mocenigo]

Rather than NVA, I would suggest to take a look at the Quad Artera series. It seems quite good and for a fair price. For the price of a Sugden A21SE one can get a preamp and two monoblocks that would put the A21SE to shame. The series includes also an inexpensive integrated.

 

[DavidEdwinAston]

Rather than NVA, I would suggest to take a look at the Quad Artera series. It seems quite good and for a fair price. For the price of a Sugden A21SE one can get a preamp and two monoblocks that would put the A21SE to shame. The series includes also an inexpensive integrated.

As the owner of an Artera preamp, and two Platinum Mono's, I absolutely agree with your post mocenigo.

 

[mocenigo]

As the owner of an Artera preamp, and two Platinum Mono's, I absolutely agree with your post mocenigo.

I have just one question. Do they hum? Apparently Quad connects the XLR connectors in the AES recommended way (to signal ground) whereas the "consumer audio" way is to chassis ground. So in some cases one may get hum by joining devices that different standards. (I use signal ground in my build, and never had any problem.)

 

[DavidEdwinAston]

I have just one question. Do they hum? Apparently Quad connects the XLR connectors in the AES recommended way (to signal ground) whereas the "consumer audio" way is to chassis ground. So in some cases one may get hum by joining devices that different standards. (I use signal ground in my build, and never had any problem.)

While I don't understand the technical side of your post, sorry. I would say no audible hum except very briefly at switch on from each mono. I am normally switched off at the mains. So, turn on at the wall into standby, each mono shows a red light. Press each red lit button to turn on. The brief hum, and after perhaps fifteen seconds, each machine turns fully on.