ARCAM A39/ROKSAN K3 AMPS........ANYONE HEARD THEM ?

[audioaddict]

Just wondered if anyone has heard the arcam and roksan amps............guessing both will be great sounding though kinda wish arcam would revamp their styling a little bit...........any thoughts guys ?

 

[CnoEvil]

Is the A39 even available yet?.......I know my dealer is still waiting on the A49, and I think it came out first.

 

[Philim]

Heard the k3 at the weekend. I disliked it as much as the k2.

 

[Happy_Listner]

I don't think anyone has heard them yet. The above post said he did and didn't like the K3? Care to elaborate? Give some system details and where you heard it at?

The k3 looks really interesting. Not sure if the K3 is supposed to be a replacment for the K2 BT? Both will have the BT. The K3 is quite a bit more expensive. I read the faceplates are made in Germany but the rest of the amp still in England.

The Arcam A39 looks interesting as well. It is run at Class A up to 20 Watts. It is then a class G amplifier. I heard thier AVR hometheater amp based on this same Class G amplifier design and it sounded great driving Martin Logan speakers.

Sadly, unlike the previous A38, this A39 amp is now made in China like most other Arcam gear these days. Apparently no cost savings passed on to the consumer. If I remember right the A39 now comes with phono but has no MC option like the A38 had.

The A49 should be a real beast, able to drive just about anything. Oddly it will be made in the USA.

Thats all I know, sorry I have no listening impressions yet to share.

 

[Vladimir]

If Arcam A39 can manage 20W of Class A per channel on such small heatsinks, it must be a really efficient design. Maximum theoretical efficiency for class A is 50%, which means to provide 20Wpc, the amp needs to dissipate constantly even at idle at least 40Wpc. The bigger brother, Arcam A49 produces 200Wpc in 8 ohms out of which 50Wpc are Class A! *shok*

To illustrate how massive that 50W is, look at this Krell KRS-100 monoblock. It has "only" 100W in Class A and look at the heatsink realestate and the size of its power supply.

I was currious how Arcam engineers achieved this so I had a look into Class G. This is some geeky but really cool stuff.

Class-G amplifiers (which use "rail switching" to decrease power consumption and increase efficiency) are more efficient than class-AB amplifiers. These amplifiers provide several power rails at different voltages and switch between them as the signal output approaches each level. Thus, the amplifier increases efficiency by reducing the wasted power at the output transistors. Class-G amplifiers are more efficient than class AB but less efficient when compared to class D, however, they do not have the electromagnetic interference effects of class D.

Source: in this brochure.

How Audioholics explain Class G:

Another pair of designs engineered with an eye towards improved efficiency, technically speaking neither Class G nor Class H amplifiers are officially recognized. Instead, they are variations upon the theme of Class A/B, utilizing voltage rail switching and rail modulation respectively. In either case, under low demand conditions, the system utilizes a lower rail voltage than a comparably rated Class A/B amplifier, significantly reducing power consumption; as high power conditions arise, the system dynamically increases rail voltage (i.e. switches to the high voltage rail) to handle high amplitude transients.

So what’s the drawback here? In a word: cost. Original rail switching designs utilized bipolar transistors to control the output rails, increasing complexity and cost. These days, that is often reduced to an extent with the use of high current MOSFETs to select / vary the rails. Not only does the use of MOSFETs further improve efficiency and reduce heat, but fewer parts are required (usually one device per rail). In addition to the cost of rail switching / rail modulation itself, it’s also worth noting that some Class G amplifiers utilize more output devices than a typical Class A/B design. One pair of devices will act in typical A/B fashion, fed by the low voltage rails; meanwhile another pair is held in reserve to act as a voltage booster, only activated as the situation demands. At the end of the day, because of these additional costs you’ll usually only see Class G and H associated with high powered amplifiers where the increased efficiency makes it worthwhile. Compact designs may also leverage Class G / H topologies as opposed to Class A/B given that the ability to switch to a low power mode means they can get by with a slightly smaller heatsink.

 

[audioaddict]

wow that is serious amplification..........i asked about the a39 as sevenoaks are advertising it now on their website so assumed it was available...........good info vlad

 

[p_m_brown]

The A49 sounds lovely. I heard it a couple of weeks back at Hifi Lounge. Powerful deep and tight bass. Started and stopped instantly, zero overhang, not heard anything quite like it. Best part of £4k though!

If the A39 sounds anywhere as good it'll be time for a proper audition me thinks especially at £1500!

 

[audioaddict]

thats what i was thinking around that price

 

[audioaddict]

thats what i was thinking around that price

 

[audiodarkness]

My dealer had the A49 playing in the shop when I was in today, it seems nice enough. Typical Arcam sound to me, warm, smooth, very musical. I believe its being made in America rather than China?

 

[Jota180]

My dealer had the A49 playing in the shop when I was in today, it seems nice enough. Typical Arcam sound to me, warm, smooth, very musical. I believe its being made in America rather than China?

The 49 is made in the USA.

 

[Smcurry3]

I heard the Arcam A39 about two weeks ago. It has an expansive sound stage and you can hear the detail of each instrament even at very low levels. When auditioning the Arcam A39 It was paired with an Arcam CD Player and B&W 804 Diamond speakers. My first thought was the B&Ws were adding to the sound stage so I swapped them out with a pair of Paradigm Studio 20s. This had no affect on the soundstage what so ever. Also, I was very impressed and surprised with the amount of low end that you receive with the Arcam. My normal listening speakers are the Paradigm Studio 20s. These normally need a sub but with the A39 a sub becomes optional on a lot of pieces.

I was originally looking at the the Arcam A19 but after hearing the A39 I am leaning in its direction. Although it it substantually more money it seems like an obvios choice. I have found little else that can touch it for the types of music I listen to for the price.

For those wondering, I did take the A19 home to to test. The A19 was tested with the Arcam irDac, Paradigm sudio 20s and a Deff Tech supercube 4000 sub. Overall it's a pretty impressinve integrated amp. It expresses detail, clarity, great lows and a large soundstage. I have tested several Rotels and Marantz, none of which can touch the Arcam.

I am currently waiting for a cambridge audio stream magic 6 v2 to arrive which I will be testing with the Arcam A39. Most of my music is digital (FLAC & AAC) so I am trying to find a happy pairing with a network streaming DAC.

 

[Frank Harvey]

We've had the A39 and K3 in for a few weeks now, but unfortunately I've not had a chance to hear them yet, partly because I've been on holiday last week. Will be interesting to put the Arcam up against the Rega Elicit-R and Naim Nait XS2.

 

[FanthorpesHiFi]

To me, having heard both over the last week. I find the presentation of the A39 to be big, smooth yet clean. There seems to be a good amount of headroom and space to the soundstage. It's very much in keeping with the signature Arcam sound.

The Roksan K3 has a slightly more edgier sound. It's stronger in the midrange with a more forward presentation. I didn't find it hard or fatiguing just a little more punchy.

Obviously speaker matching and room acoustics are key as always. I heard them with PMC 22 and a Cyrus streamer.

 

[obiwan kenobi]

I heard the Arcam A39 about two weeks ago. It has an expansive sound stage and you can hear the detail of each instrament even at very low levels. When auditioning the Arcam A39 It was paired with an Arcam CD Player and B&W 804 Diamond speakers. My first thought was the B&Ws were adding to the sound stage so I swapped them out with a pair of Paradigm Studio 20s. This had no affect on the soundstage what so ever. Also, I was very impressed and surprised with the amount of low end that you receive with the Arcam. My normal listening speakers are the Paradigm Studio 20s. These normally need a sub but with the A39 a sub becomes optional on a lot of pieces.

I was originally looking at the the Arcam A19 but after hearing the A39 I am leaning in its direction.

I'm very interested in the Arcam A39. But will it be a good match with Kef R500 speakers? I like with my music, most metal, a warm and darker sound. I've heard the Exposure 3010S2. Good amp, but not warm enough for me and (female) vocals too bright and agressive for me. Here in the Netherlands i can buy the A39 for 1600,-- Euro.

 

[drummerman]

Most decently and well engineered modern SS amplifiers have vanishingly low distortion.

Is there really still a need for 'class A' or is it just a buzz word and USP?

regards

 

[CnoEvil]

Most decently and well engineered modern SS amplifiers have vanishingly low distortion.

Is there really still a need for 'class A' or is it just a buzz word and USP?

regards

Is there a need for Hi-Fi?.....it's certainly not a requisite, more of a preference.

 

[drummerman]

Is there a need for Hi-Fi?.....it's certainly not a requisite, more of a preference.

My remark was less philosophical more technical;

How much distortion is audible and after that ... ?

regards

 

[CnoEvil]

Is there a need for Hi-Fi?.....it's certainly not a requisite, more of a preference.

My remark was less philosophical more technical;

How much distortion is audible and after that ... ?

regards

My amp has very low intermodulation distortion and just so happens to be one of the best sounding amps I've heard under £10k....as measured and commented on here (second last para at bottom of p28):

http://www.bm.rs/Musical%20Fidelity/Musical%20Fidelity%20AMS-35i%20-%20Australian%20HiFi.pdf

 

[obiwan kenobi]

What about the MF M6si. Anyone heart it?

 

[Vladimir]

I've edited my post. Check it out.

 

[Vladimir]

My amp has very low intermodulation distortion and just so happens to be one of the best sounding amps I've heard under £10k....as measured and commented on here (second last para at bottom of p28):

http://www.bm.rs/Musical%20Fidelity/Musical%20Fidelity%20AMS-35i%20-%20Australian%20HiFi.pdf

Measurements on the old Roksan Kandy K2, class AB integrated amp.

IMD achieved into 8.0ohm (2nd-order) re. 19000/20000Hz =

0.00303% @ 12.0W (Left Channel)

0.00109% @ 12.1W (Right Channel)

Source: Miller Audio Research

So, you can hear under 0.003% IMD Cno? Maybe you can, subjectively.

On the Cyrus 8a, class AB integrated amp.

IMD achieved into 8ohm (2nd-order) re. 19000/20000Hz =

0.00021% @ 10.0W (Left Channel)

0.00044% @ 10.0W (Right Channel)

Source: Miller Audio Research

On the Musical Fidelity AMS100, class A power amp.

IMD achieved into 8ohm (2nd-order) re. 19000/20000Hz =

0.00022% @ 9.9W (Left Channel)

0.00044% @ 10.0W (Right Channel)

Source: Miller Audio Research

It actually has more IM distortion than the shoebox class AB Cyrus integrated. Awww... *nea*

 

[CnoEvil]

My amp has very low intermodulation distortion and just so happens to be one of the best sounding amps I've heard under £10k....as measured and commented on here (second last para at bottom of p28):

http://www.bm.rs/Musical%20Fidelity/Musical%20Fidelity%20AMS-35i%20-%20Australian%20HiFi.pdf

Measurements on the old Roksan Kandy K2 (Class AB, runs very cool)

IMD achieved into 8.0ohm (2nd-order) re. 19000/20000Hz =

0.00303% @ 12.0W (Left Channel)

0.00109% @ 12.1W (Right Channel)

Source: Miller Audio Research

So, you can hear under 0.003% IMD Cno? Maybe you can, subjectively.

I'm only pointing out that there is a possible correlation between what I think sounds well and the type of distortion a good Class A removes. I will let more knowledgeable folk draw their own theoretical conclusions from the quoted measurements.

If you'd heard what I have heard, you might even feel the same.

 

[Vladimir]

£13,000

£1200

 

[alesco2010]

I have the Arcam A39 since last October. Even with my old CD player Rotel and a pair of Dynaudio Exite X12 bookshelf, the sound is incredible. Cristal, warm, with very strong bass at low volume. My Dynaudio Exite are 120 watts at 4 ohms, so even in a large room it´s imposible to go further than 50 % with the amp power. A beast.

No distortions. So cristal and with no control for bass and trebble, that I have started to put in the trash half of my cd collection. This is an amp to listen excellent recordings or suffering.

You should be a long experienced audiophile with teenager´s ears to pretend more than this. My next step will be an irDAC. I love listening the Philarmonic of Berlin in HD TV and the DAC will be a good improvement