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SoundRebels
March 15, 2014, 07:38 AM
Jeff Rowland Corus + 625 review: Jeff Rowland Corus + 625 English ver. (http://soundrebels.com/artykuly/recenzje/item/282-jeff-rowland-corus-625-english-ver)

http://soundrebels.com/media/k2/items/cache/2e2c1711fe12b24ae23d95c35bfd21c2_XL.jpg

Bobvin
March 15, 2014, 11:04 AM
I tried reading that review, but the white text on the black background started giving me a headache after about two paragraphs. When are web designers going to learn readability should trump style. There are at least a dozen ways to do it better, and maintain style.

Just look up after reading for a couple minutes, see how long your eyes need to adjust. The audio community makes this mistake frequently and yet us folks with the old eyes are the ones who are buying the gear. Maybe a consideration for the audience they are trying to reach?

(Sorry for the off topic rant, I was involved in early web design usability when I was at Microsoft, back when I.E. was at v2. Amazing how much info about readability exists yet designers insist on this hyper-contrast white on black.)

SoundRebels
March 15, 2014, 11:22 AM
Bobvin - Thanks for Your opinion. We want and need feedback like this, and try to introduce some improvements in the future.

LenWhite
March 15, 2014, 05:33 PM
I own the JRDG Corus and 625 combination and I love the looks and sound. But these sentences in your review confused me since I know of know way to control the 625 with the Corus remote.

"The 625 power amplifier looks much more richly, and at the same time very elegant. The front bears only a centrally placed, surrounded with a while ring, indicating the power state, power button. Also the remote controller can be used to toggle between power-on and standby."

kiwi_1282001
March 15, 2014, 06:06 PM
I tried reading that review, but the white text on the black background started giving me a headache after about two paragraphs. [...]

+1. Unfortunate such an important review should exhibit such poor readability. I needed to cut and paste the review into a word document in order to read it in one sitting.

SoundRebels
March 15, 2014, 06:46 PM
I know that it looks like aspirin for serious disease, but You can use browsers extensions like High Contrast in Chrome ( https://chrome.google.com/webstore/detail/high-contrast/djcfdncoelnlbldjfhinnjlhdjlikmph )

GuidoCorona
March 15, 2014, 08:29 PM
I confirm that the standby function, available on Corus front panel and remote, toggles standby/operate on Corus, but has no effect on M625 or other power amplifier.

There exists a 12V standby remote input trigger on M625, but it requires a wire connected to a 3.5mm Jack on M625… And control is usually performed from an AV receiver.

My own experience with M625 and with Criterion (very similar to Corus) is that break-in extended for about 1K hours. Furthermore, after significant standby time, sonic optimization was usually obtained after 24 hours of operating the live system with an audio signal going through it.

On the subject of human factors / accessibility… The white on black background is sometimes applied to improve the reading experience for readers with low vision… E.g. many seniors. However, W/B is in most cases too radical a medicine. In general, a 4:1 foreground/background contrast ratio is more than sufficient. It is best to style colors using CSS, so that users can override with their own custom CSS, or inherit high contrast system colors, or apply color overrides from magnification software. I also noticed that the lang=”pl” HTML attribute sprinkled all over the English page is incorrect… It should be lang=”en”. The lang attribute is used to direct screen reading software to load language-specific text-to-speech modules, and read the page with that module…. If I had a Polish synthesizer in my system, that article would have been read using Polish reading rules, making the text impenetrable.

G.

Mike
March 15, 2014, 08:46 PM
Guido - good to see you as always! Thanks for your help the other day. I'm still waiting anxiously. :)

Let me tell you guys, Guido might be one of the smartest guys I've ever met in Audio. Glad I got to meet him at RMAF too.

kiwi_1282001
March 16, 2014, 04:25 AM
[...] Let me tell you guys, Guido might be one of the smartest guys I've ever met in Audio. [...]

Yes! I enjoy reading Guido's published work and his significant contribution on many audio forums. Each contribution is without fail thoughful, insightful and interesting and always written in a competant and professional manner. Makes me think that along the way Guido must have had some great teachers! As the old saying goes, behind every professional there is a professor.

SoundRebels
March 16, 2014, 07:31 AM
I confirm that the standby function, available on Corus front panel and remote, toggles standby/operate on Corus, but has no effect on M625 or other power amplifier.

There exists a 12V standby remote input trigger on M625, but it requires a wire connected to a 3.5mm Jack on M625… And control is usually performed from an AV receiver.

(...)

G.

Info about standby option is available in 625 features - Model 625 (http://jeffrowlandgroup.com/us/amplifiers-model-625.html)
"Rear Panel Remote Jack
12V 3.5mm jack on rear panel permits amplifier power on/standby switching in remote and home theater applications."

mep
March 16, 2014, 10:28 AM
I own the JRDG Corus and 625 combination and I love the looks and sound. But these sentences in your review confused me since I know of know way to control the 625 with the Corus remote.

"The 625 power amplifier looks much more richly, and at the same time very elegant. The front bears only a centrally placed, surrounded with a while ring, indicating the power state, power button. Also the remote controller can be used to toggle between power-on and standby."

Are you sure you know what you think you know? Or do you think sometimes you need the word 'no' instead of 'know?' :D

GuidoCorona
March 16, 2014, 04:51 PM
Thank you Mike and Kiwi for your kind words… Just don’t keep ‘em up… They’s already goin’ to my head, and…. I’ll end up a Fat-Head audiophile before long, and those teachers who have not disowned me yet, will promptly do so *grins!*

Hi Soundrebels, you are right, the standby/power relay circuit of most Rowland Amps, including M625, usually operated from the front temporary contact switch, is also operable with a 12V pulse from a wire plugged into the 3.5 mm socket in the back of these devices. However, no Rowland linestages that I know of have the capability of generating such a 12V control pulse. signal.


Saluti, G.

hongkong
October 27, 2015, 08:03 PM
I have choose Jeff Rowland Corus because I can connect my home cinema with the special entry 'Bypass'.
It's a good idea.
Corus is above my Proceed PRE.

GuidoCorona
October 27, 2015, 08:09 PM
Hong Kong, Corus is a fantastic amp... If you ever decide to move up to M625 S2, you will have an unbeatable pair... M625 has significant enhancements over the original... Everyone who heard it seems to agree that it is an amazing device. G.

hongkong
October 27, 2015, 08:46 PM
Hi,

CORUS is a preamplifier.
I have the Jeff Rowland model 625 version one.
Only Furutech Lineflux give me a good difference between Audioquest, Van Den Hul and pro cable.

GuidoCorona
October 27, 2015, 09:20 PM
Hi Hong Kong, with Rowland electronics I have found better synergy with Shunyata, High Fidelity Cables, and Nordost Valhalla V2 than with FureTech Flux.... Flux seems to be a little hard sounding with Rowland gear.

Guido

hongkong
October 28, 2015, 01:44 AM
Thank you Mike and Kiwi for your kind words… Just don’t keep ‘em up… They’s already goin’ to my head, and…. I’ll end up a Fat-Head audiophile before long, and those teachers who have not disowned me yet, will promptly do so *grins!*

Hi Soundrebels, you are right, the standby/power relay circuit of most Rowland Amps, including M625, usually operated from the front temporary contact switch, is also operable with a 12V pulse from a wire plugged into the 3.5 mm socket in the back of these devices. However, no Rowland linestages that I know of have the capability of generating such a 12V control pulse. signal.


Saluti, G.


I'm agree with you.

hongkong
October 28, 2015, 01:49 AM
Hi Hong Kong, with Rowland electronics I have found better synergy with Shunyata, High Fidelity Cables, and Nordost Valhalla V2 than with FureTech Flux.... Flux seems to be a little hard sounding with Rowland gear.

Guido

Jumperflux for my loudspeaker is better than orginal's jumper.

I have all in Van Den Hul before : the Second and the Revelation for loudspeaker.
I haven't change my power cord : it's just DIY..
I'm going to work now....

hongkong
September 5, 2016, 05:57 AM
Hi Hong Kong, with Rowland electronics I have found better synergy with Shunyata, High Fidelity Cables, and Nordost Valhalla V2 than with FureTech Flux.... Flux seems to be a little hard sounding with Rowland gear.

Guido

Hi GuidoCorona, after near one year, I could say : you are right, Flux seems to be a little hard sounding with Rowland gear.

The gain with jumperflux is real : better treble and medium.
With speakerflux, better bass, more accuracy and more detailed.

I have Van Den Hul before, I have keep them.

I have test Van Den Hull, the second between DAC 360S and Corus : voice are warm, voice with Lineflux are a little hard.

I have test too bi-amp with my older Proceed AMP2.

Model 625 for bass and AMP2 with Van Den Hul for treble and medium...very strange : bass seems better and voice seems warmer.

I have a pro cable for the clock : it's very hard...so, I prefer let Van Den Hul for digital 75 Ohms -> Clock Grimm -> Lineflux 300 Ohms -> DAC 360S.

I need more time to try other solutions.

I have DIY power cord. With the Model 625, I have many differencies - I let it power cable 3x4mm2.
I have no difference for the Grimm Clock between Olflex 110 and power cable 3x2.5mm2.
I have pass an order with power cable 3x4mm2, I wait them.
See you next time ...when I have do other test.

GuidoCorona
September 5, 2016, 05:42 PM
Hi Hong Kong, glad reading from you again!

I am not surprised that you found Flux not to be quite in synergy with your Rowland M625 and Corus. M625 are extremely extended and evenly revealing across the frequency spectrum. My experience is that Rowland products are at their best when matched with wiring that exhibits similar behavior... Hence Shunyata, Nordost Valhalla II, and Cardas Clear and Clear Beyond.... Perhps Vandenhull behaves the same way.


You might be interested in knowing that since last year Rowland has released two products that you might find intriguing....

* The Power Storage Unit (PSU) is a full chassis that replaces the Corus power supply with an ultra-capacitor based power supply that takes Corus completely off the grid 24/7.... There are two parallel banks of ultra-capacitors.... While one delivers pure DC to Corus and/or Aeris, the other bank gets recharged... When the first bank reaches set level of discharge, roles are switched automatically and the cycle repeates. The transition between capacitor banks is completely transparent to the user... Both from an operational and an audio point of view. PSU would isolate Corus 100% from the grid, and so eliminate any noise from the AC line.... Furthermore, ultracaps are much superior to batteries at serving precision audio circuits that need to deliver transients. To all reports, the audible result is a much more palpable black background with better defined images and stage... PSU has been launched in ASIA at the recent audio shows and the first batch was immediately sold out because of the enthusiasm of customers and distributors.


* Meantime, the M625 has now a 2nd generation series, called M625 S2. Apparently there are considerable circuit changes, and according to ROwland, he has achieved distrortions so low that he can no longer measure it.... He now uses four M625 S2s to power the home system in his factory.

These two products can now be ordered from Rowland dealers and are now shipping.

Regards, Guido

hongkong
September 9, 2016, 04:55 AM
Hi Hong Kong, glad reading from you again!

I am not surprised that you found Flux not to be quite in synergy with your Rowland M625 and Corus. M625 are extremely extended and evenly revealing across the frequency spectrum. My experience is that Rowland products are at their best when matched with wiring that exhibits similar behavior... Hence Shunyata, Nordost Valhalla II, and Cardas Clear and Clear Beyond.... Perhps Vandenhull behaves the same way.


You might be interested in knowing that since last year Rowland has released two products that you might find intriguing....

* The Power Storage Unit (PSU) is a full chassis that replaces the Corus power supply with an ultra-capacitor based power supply that takes Corus completely off the grid 24/7.... There are two parallel banks of ultra-capacitors.... While one delivers pure DC to Corus and/or Aeris, the other bank gets recharged... When the first bank reaches set level of discharge, roles are switched automatically and the cycle repeates. The transition between capacitor banks is completely transparent to the user... Both from an operational and an audio point of view. PSU would isolate Corus 100% from the grid, and so eliminate any noise from the AC line.... Furthermore, ultracaps are much superior to batteries at serving precision audio circuits that need to deliver transients. To all reports, the audible result is a much more palpable black background with better defined images and stage... PSU has been launched in ASIA at the recent audio shows and the first batch was immediately sold out because of the enthusiasm of customers and distributors.


* Meantime, the M625 has now a 2nd generation series, called M625 S2. Apparently there are considerable circuit changes, and according to ROwland, he has achieved distrortions so low that he can no longer measure it.... He now uses four M625 S2s to power the home system in his factory.

These two products can now be ordered from Rowland dealers and are now shipping.

Regards, Guido

Hi Guido,

Thank you for this precious information.
With the Corus, I have try this :
- power cord provide by Jeff Rowland : sound is good
- power cord provide by REAL CABLE : sound is poor - no bass, no treble, only medium and it's not beauty...sound is like a stupid radio ( ok , it's a picture)
- power cord provide by Furutech : sound is good as the power cord by Jeff Rowland - no difference - strange ...
- power cord provide by me (DIY) : sound is good - cable is 3 x 2.5mm2(2.5mm2 = near 13 AWG )
- power cord provide by me (DIY) : sound is good - cable is 3 x 2.5mm2(2.5mm2 = near 13 AWG ) but it's armored (I'm not sure it's the good word) - a little more bass and treble, medium is a little hard.
- power cord provide by me (DIY) : sound is good - cable is 3 x 4mm2(4mm2 = near 11 AWG ) - not tested (I wait cable)

With the Model 625, I have try this :
- power cord provide by Jeff Rowland : sound is good
- power cord provide by REAL CABLE : no test : not have IEC C20
- power cord provide by Furutech : no test : not have IEC C20
- power cord provide by me (DIY) : sound is good - cable is 3 x 2.5mm2(2.5mm2 = near 13 AWG )
- power cord provide by me (DIY) : sound is strange - cable is 3 x 2.5mm2(2.5mm2 = near 13 AWG ) but it's armored (I'm not sure it's the good word)
I can explain it, but sound is not good, there is no musicality - it's very strange.
- power cord provide by me (DIY) : sound is very good - cable is 3 x 4mm2(4mm2 = near 11 AWG ) - there is more bass and dynamics.

And what is funny ?
- power cord provide by Jeff Rowland : price ??
- power cord provide by REAL CABLE : price = 200 Euros = near 200 US$
- power cord provide by Furutech : price = 800 Euros = near 750 US$
- power cord provide by me (DIY) : price = 2 connectors + cable 2 meters = perhaps 15 Euros + 2 hours to do it (Yes, I'm a turtle...not a ninja turtle...laungh !)
- power cord provide by me (DIY) : price = 20 Euros perhaps 18 US$ - cable is 3 x 2.5mm2(2.5mm2 = near 13 AWG )
- power cord provide by me (DIY) : price = 30 Euros perhaps 25 US$ - cable is 3 x 4mm2(4mm2 = near 11 AWG )

So I give you my opinion when I test power cord 3 x 4 mm2 in a few days...

hongkong
September 12, 2016, 02:57 PM
Hi,

I receive the power cord and I assemble the shuko and the IEC C19.
With the power cord - cable is 3 x 4mm2(4mm2 = near 11 AWG ), the sound is very good, much warm...and accuracy is here too...
I will make the other cables for my other products when I have time.

GuidoCorona
September 12, 2016, 03:14 PM
Hi Hong Kong, glad that your DIY wire is working out.... Keep it exercised as much as you can for the next couple of weeks... Usually a cord takes some 300 hours to stabilize.... Do keep us posted.

Regards, Guido

hongkong
September 12, 2016, 03:21 PM
If I have time, I do photo and give the name and the reference of the cables I use, and connector, but it's not Schuko in USA.
I don't know if you find them in USA.
I have bought them in Germany.

I have do the test with the Corus.

I would change the power cord for the clock, after for the DAC and for the end, the SACD/CD player. Then I have change all my cable for the digital components.

hongkong
October 29, 2016, 09:30 AM
http://www.audioshark.org/attachment.php?attachmentid=17653&stc=1

Hi, cables behind my hifi....
In black, 3 x 4 mm2 not blinded
In white, 3 x 2.5 mm2 not blinded
The third color is : 3 x 2.5 mm2 blinded

Electricity arrived directly from my electricity box(I don't know the term in american language, sorry, some help ?) with 2 x ( 2 x 6 mm2) :
One for my home-cinema and one for my hifi.