Question about Class A

@ronald8 , my speakers are 92db.

That is one thing that I am afraid of, that I acquire a Class A device like the Sugden but don't really hear a significant difference from what I have now (at least in my system).

Hi Jay78,

In my opinion, I don't think there is a difference in sound.  I have Klipsch La Scalas with efficiency of 101 to 104 dB.   I experimented with Schiit Aegirs (essentially Class A), Black Ice 3502s and Cary 120S Mark II.  I actually had a twinge of buyer's remorse with the Black Ice and the Aegirs and thought they did not have significant SQ improvement over my Outlaw 2200 monoblocks.  With the La Scalas, the amps are always in Class A.   It was a nice experiment:  in the long run, it probably may not be a good return on investment.  I like the Cary because it keeps my basement warm in the winter.  It is a hot beast as it runs in Class A in triode mode at 60 watts.  I would never use it in the spring or summer.  Class A amps are essentially gorgeous space heaters.

This may not help, but it depends.  If you have efficient horn loaded speakers > 95 dB/watt-meter, you may hear a difference. 

...Or not. My speakers are 98dB and we make class A amps; we also make class D amps and they sound very similar. Class A is a means of theoretically reducing open loop distortion but like all things its a matter of execution.

Just curious: I am thinking about by-amping my speakers (Quantum 2). With low/mid, mid/high and high being the high pass from 200 Hz (200/600/4000), how much power is needed? 

The idea is to use mean brute amp for thw Watkins (dual coil, dual crossover) woofer (dipping below 2 ohm), and a class A (or tube?) for the high pass.

Does someone know the percentage (for example white or pink noise) of sound energy above 200 Hz (vs below 200 Hz)? Maybe the term is 'spectral energy'? 

Less scientific: Using 200 Watt input (rated at 350 W RMS) how much power goes to low pass ( under 200 Hz, woofer) and how much to the high pass (above 200 Hz)?

So I went to the local dealer today that I mentioned earlier to hear the Sugden.

He only had the A21S available to hear.

It sounded good but of course how it will sound in my system would be different.

He had it hooked up to a HiFi Rose and Klipsch Heresy's (I believe).

If he had the A21SE in stock, I might have actually bought it today. 

But he states it's $3700 and he can order it.

I can understand with the current way things are, that prices can go up but I can't do $3700. I would have gone for it at the $3250 prices that I have seen.

I figure since I am willing to spend the money and if I want Sugden, then I want to get the A21SE and not settle for the A21S (which in no way is a bad unit) but I don't want to feel that I settled later.

So the journey continues.

What speakers do you have and whats their efficiency? If Magnepans, I can tell you Aegir isn't a good match, nice sound but 85db efficient speakers make it sound stressed and clip protection will cut in at loud passages. ASR didn't find that running them as monoblocks gave that much more headroom.

really important to know your speakers impedance curve/efficiency and to look for trustworthy reviews that used your speakers with different amps. An amp thats  ho-hum with one speaker can work well with a different speaker.

I have Martin Logan Motion 40's, 4-ohm and 92db sensitive. 

@jay73 

try the Coda 11 mentioned.   100 wpc class A to output.  Should you decide to swap speakers,  the Coda will allow for future updates.   I have zero affiliation with Coda the company,  or the preowned being sold. 

respectfully, 

jose

At 3X the price the Sugden A21SE had better prove an improvement over the Vincent SV-500.  Actually any of the A21 series should be.

I would not advise the purchase of an amplifier with intentions of using your Vincent as a pre unless you are planing on replacing the Vincent with a higher end preamp in the near future.

Keep your eyes open for a used Sugden A21 series integrated. Should you find one you could purchase it, compare to your Vincent and keep the one that fits best into your system. Sell the other. 

As an aside to your original quarry, have you considered the purchase of an external DAC to replace the one internal to the Vincent?  Improvement in your source may prove to be a better expenditure.

If your speakers are truly 92db sensitive (sometimes mfg's over-rate them), I'd recommend the Pass-Labs 30.8 stereo amp.  Definitely punches way above it's 30WPC rating and has plenty of power-supply for 4-ohm speakers.  My 94db speakers 6-ohm impedance would play very loud and they seldom moved the meter needle !  Great sounding amp and does 30WPC in pure class-A, and I believe 60WPC into 4-ohms in class-A.  Really a power-house amp and highly recommended...  

Jay, if you can find one, the Luxman L-550AX should run around $2500/3000, used and in very nice condition. They're 20W class A, then switch to A/B. I own an L-590AX, which is 30W, I bought it used for $4300, and it looked like new. That amp is one iteration older than the newer, but recently discontinued L-590AXII. Prices vary, some folks ask pretty high prices for a used L-590AXII, but they come up at times for more reasonable money. I believe the models, from oldest to new are A, AII, AX, AXII. Hope this helps, they're great amps.

Jay ,

You can spend yourself blind sorting through the different class A components that are available. There are some great suggestions in this feed but consider the efficiency of your speakers and go to your dealer to listen on a few options. Some dealers even let you take items home for a test drive which may be best. I personally settled on a small flea wat amplifier that only puts out a couple of watts per side, but this is married to a set of really high efficiency Klipsch speakers. Unfortunately it's going to be different for every user. For your budget however I would encourage you to consider Schiit Freya+ and a pair of their monos! They can drive most speakers and they put out pure class A to a point. With class A you will find that you only are using the first five or 10 Watts anyways so don't worry so much about having a ton of power. The nice thing about this company is they are a US company and they will let you test drive in your home no questions asked. Hope this helps and happy Sonic Bliss

Well Folks, I did it, I done did it.

As mentioned earlier, I had heard the A21 yesterday at a local dealer but he didn’t have the A21SE in stock and his price was too much for me.

So I came home and searched around and found a dealer in TX selling through eBay.

Well I took the chance and bought it!

The A21SE should be arriving around 2/23. The dealer offers 30 day returns.

Looking forward to this Amp.

As I mentioned before, my speaker are 92db sensitive (at least according to the Martin Logan), so I am hoping it will be a good match.

@mesch , I have a external dedicated DAC, the Questyle CMA400i, which I feel is a really nice piece.

Once the amp gets here, of course I will be comparing to my Vincent. I am really hoping it’s going to be on another level then the Vincent.

I will let you know how it goes.

I really appreciate all the feedback.

Any owners of Sugden Amps, please also chime in.

Thanks

Congrats on your purchase! Please let us know your thoughts after comparison to your Vincent. I am thinking you are going to be very happy.

I had forgotten your were using an external DAC when making my last post. 

I contacted Tone Import (the official distributor for Sugden in the US) to inquire about official dealers, I was just curios.

So I am awaiting their reply but they did inform me that the price for the A21SE is now $3750.

$500 jump from the previous $3250. So the audio dealer that I had visited over the weekend was correct, the price has gone up.

Darn economy, supply chain and inflation, ha.

So I got the Sugden in and listened to just a few tracks last nite before I had to go to bed.

Question about the speaker posts on the amp. So I haven't come across the type of speaker posts that the Sugden has before.

There seems to be a a ring that you can loosen to accept spades and if you are not using spades, I suppose you tighten up. But right behind that ring, there seems to be another piece that turns (which accommodates banana plugs).

At first, it seemed liked I couldn't insert my speaker wires (Audioquest Type 4 Banana) but turn that piece (as if I was unscrewing it), now speaker wires seem to be able to go in.

I assuming that is so for different sizes of banana wires?

I'll have to inspect more. Fortunately, headed into a 3 day weekend, so I should be able to spend some time with amp now.

But wanted to get anyone's feedback on the type of speaker posts/jacks that Sugden has (if you have any experience with it).

Thnx

https://www.sugdenaudio.com/how-to

Wow, this is great!

Thanks so much for this.

I really appreciate it.

Nice! That is slicker than cat poop!  Looking forward to your impressions. 

Well, I thought I would post an update.

I received the Sugden A21se a few weeks ago and have been listening to it whenever I get a moment. The only times I really can listen wholeheartedly is in the late evenings when the wife goes to bed and things outside settle down (unfortunately I have some noisy streets) and even then, the weekends are really the best time for me to listen.

So far, I don't notice a huge difference between the Sugden and my Vincent. But I would say that is probably because of the rest of the equipment. Perhaps if the Sugden had better equipment to play with, it could shine even more.

Right now it feels like, if both were considered sport cars, perhaps the Sugden would be ahead but if you looked in the rear view mirror, the Vincent is not too far behind.

It's probably too early to tell. I need to spend more time with it.

In no way, does it sound bad. I think certain tracks whether digital or vinyl have caught my attention but need more time.

Now, I am thinking I want to use both amps. I may purchase a quality switchbox. I have contacted Decware and Mapletree regarding their offerings.

So that is my quick update for now.

Unless I missed it, nowhere herein did you state the other components of your system.  Remember you are listening to a system, not a single component.

I would not involve a switch box. Listen to the Sugden for a while. Then replace with the Vincent. Repeat with extended listening sessions. The experience will lead you to understand what sonic attributes are most important to you. 

Another question, what is size of your room?

@mesch 

I did list some of my components earlier in the thread but here is what I am working with:

- Martin Logan Motion 40 Speakers
- MoFi Studio Deck TT w/Hana SL MC
- Questyle CMA400i DAC
- Playing with 2 different phono pre-amps at the moment (Moon 110lp V2 and Jolida JD9 MK II)
- Technics SL-G700 SACD
- Windows PC used for Streaming (Qobuz) and Library of music (Flac, DSD) using Jriver

My room is about: 20' x 11' Cathedral Style Ceilings

The reason I mentioned the switch is because I really like my Vincent too and would like to utilize it sometimes.

Another option is a used class A amp,

-Luxman L series from the early 80's they are quite good and reasonable cost. also one of the higher powered class A amps out there at 50wpc. they also do not go into class AB/B.  L530,L540,L560 these amps are the predecessor to the new production Class A amps like the L590axii.  note the L560 was the last and best but rare outside Japan, i had one and its very good if you can find one (110v though). 

-Older Pass alpha series. 

-older krell 

-sungden of course. 

Cheers. 

glen 

Glad to hear that you bought the Sudgen A21SE. IMO there is also build quality to be considered when a purchase is made, and so in this case you won't have any regrets. I think that in integrated designs, the pre and power sections can be optimized for each other as intended by the designer.

  I have owned more than one great sounding piece of gear only to have it dump because of corner cutting in quality. Ever since, I am as interested in the build quality as to performance and even price.

@jay73 Sorry I missed the requested info.

I would listen to the Sudgen for a while. Let it break in. Let yourself adjust to it. After some 100 hours swap back the Vincent. Then revisit your thoughts.

@mesch 

Yes, you are correct, that is what I will need to do. Spend quality time with it and get a good sense of what it can do and then compare back to the Vincent.