Back to Jeff Rowland, now listening to Criterion and 825 :-)

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
15 to 20 years ago I started my first Jeff Rowland journey. I bought used

Coherence I Preamp

and

Model 3 Monos Amps


I liked it a lot, so I updated to

Coherence II Preamp
plus
Cadence Phono


and

Model 10 monos

after a while the PSU was failing , so Jeff updated them.


Than I had the chance to buy a pair of

Model 9 Ti/HC mono

amplifiers, which were a big step forward. As I was using that time 2 passive subwoofers, I bought a matching

Model 8 Ti/HC stereo

amplifier as well.

Looking back, I never should have sold this amplifiers. I still can remember the beauty of music reproduction with this amps.

Many speakers were coming and leaving (like Avalon Eidolon, Triangle Magellan, Von Schweickert VR6, VR8, JBL K2 and so on)
but the amps were staying and harmonizing will all of the different speakers.

After a while a Synergy iii with blue display were coming for a listening session and ist was obvious , that the new circuit Jeff Rowland has developed was outperforming my old Coherence II. So I decided to buy the new Synergy 2i , but I asked Jeff, if I can have a Battery PSU as well for this Pre.. So I was ending up with a

Synergy II I Preamp with the big model 6 amp Battery PSU,

Jeff had developed a small box with all the necessary cabling, so I was possible to combine even my cadence to this powerful BPSU.


IMGP5407 2.jpeg




The latest change was to buy the

Criterion Preamp
plus
Model 501 mono amps

in 2010

Compared to the prior Performance, I was not fully satisfied.

Than I sold all and everything from Jeff Rowland to start my Audio Note experience , which is another story.



Now nearly 10 years are gone and many manufactures served me with nice Preamps and Amps, always being a nice match to the given speakers
(like Koda, Krell, Grandinote, NAT, VTL, Conrad Johnson, Mark Levinson and many more)


Since I own the Wilson Audio Maxx 3 in my room, I have the feeling, that this speaker is a nice fit to my room size of around 65 sqm and the possible distance to side- & rear wall incl listening distance. As Wilson Audio's newer and/or bigger speakers do have similar room requirements, I might stay even longer with this brand.

Christmas 2014 we moved into the new house and now, 5 years later, it seems, that my room has done the decision, which speaker fits into :)

The Maxx 3 has seen some different amplifiers in my room, all good, but I was still looking for an alternative.

So I tried at a dealer the Goldmund Telos 2500 mono Amps. It was quite nice to listen to them, but without a reference, I cannot judge. Fortunately the dealer had a

Jeff Rowland M825 Stereo Amp

on Demo as well.

As believe, that I am familiar with the Jeff Rowland House "sound", I asked, if wen can have a comparison between the 2 amps.
(Using JRDG Corus and AR GSPRE Preamps one after the other)

To my surprise the M825 was much more close to my taste of music reproduction, even to a much lesser price point.

I never heard one of the actual JRDG amps, like 625, 725, 825 and 925, but it seems, that the performance of JRDG amps is back to what I was used to.

Listening to the M825, seeing the chassis design and built quality , the remained retail price looks like a real bargain in todays time.

JRDG has not done the big price increase step, like the most others. Price of M925 in Germany is still the same, that M9 before, even now 15 years later.

Finally I bought the M825 instead of the Goldmund Telos 2500 and was back to the Jeff Rowland brand, where I was many years before :)

It was clear, that this amp has to be partnered with Jeff Rowland Preamp, they just look too good together !

In 2010 I used the JRDG Criterion preamp and I was very familiar with all the technical design features of this Pre.

Jeff wanted that time, that a max dynamic of 140db becomes possible, so a very silent pre specification was written in his white paper.

Starting from the Coherence II i. Preamp it wa clear, that it should become a 2 chassis pre again.

The obvious logic, as he did it for years, was to split between PSU and Pre. But even splitting the remote control from the Pre was not good enough.

So the innovative concept of the Criterion was, to move the user interface, means display and all function knobs, als in to the PSU chassis and to have the Pre as such without any noise creating circuits in the separate chassis.

If you look to the Criterion Pre, the lower chassis is the Preamp and the upper chassis is the PSU with all control feature.

The PSU was also a step forward, as standard and user changeable Batteries were used, it was (is) possible with the Criterion to choose between wall outlet or Battery power to drive the Pre.

The Criterion was very expensive, similar price, than the former Coherence II, so a cheaper preamp was missing in the JRDG Portfolio.

So Jeff decided to put all circuits together in one chassis and to have a small Switch Mode PSU aside and to create the Corus Preamp.

At launch the Corus was 30% less in retail price (Germany) as the Criterion.



With this knowledge I was surprised, that nowadays the Corus has become the top of the line Preamp in the JRDG portfolio.
(now being offered for the price of the Criterion 9 years ago)

The comparison of Corus and Criterion was done already, 8 years ago. But I assume, nothing changed.

Corus sound is very clean and lean, Criterion has more substance .

My personal view with the Criterion performance is, that the 4 small balls between upper and lower chassis (Delrin?) are not the best match, as Criterion sounds a little rounded (like former Coherence II) . If you change the 4 balls to metal or ceramique (what I did) , the sound is much better. And more close to the Corus in the positive way, as Corus never had "Delrin?" feets .

With the better match of feets, the Criterion outperforms the Corus easily, what should be the normal result, if you see similarities of the Design and the 0 compromise approach of the Criterion.

Since 2 years Jeff Rowland has filled the gap, at least for the Powersupply, and he is offering a full format PSU . As the PSU usage of batteries has become a legal problem in some markets (difficult to pass the legal tests), a new type of high capacity Caps is used instead of batteries. The PSU can be used for other JRDG gear as well.

But still, in the Corus are the Display, the user interface in the same chassis...

I only heard Corus with PSU once, but not in comparison to another Preamp. JRDG Preamps are always sensitive to the power of the PSU, so I am expecting a big improvement for the standard Corus to play with the new "big" PSU.

But maybe I am a little bit old fashioned, I like the batteries in a JRDG PSU, so I bought a nearly new

- Jeff Rowland Criterion Pre Amp

from the former German Distributor to partner the M825.

Maybe I will change to Corus plus PSU, As I like to try the new Conductor Phono in the future (which will also benefit from the PSU), but I like to have the comparison of the two Preamps before.

The Criterion and the M825 are just making music together. For sure , I had better preamps in my home, but for a much higher price..
The synergy between Criterion and M825 is audible, so together they play just nice.

In combination with the Wilson Audio Maxx 3 it is a nice compromise, which will allow many hours of music listening, even if I do remember, that in particular areas my set ups before were better. Every set up is a compromise (at least for me) and to create the area of the compromise in a way, that the result does not remember you all the time, that it is a compromise, the the combination of gear becomes "art".

And for me the JRDG amps and the Maxx 3 just do it perfect together.

I can imagine, that the M925 will not change too much on the harmony, but will add some performance, so this might be also a considerable next step .

So I am finally happy to be back to Jeff Rowland .

IMG_1936.jpg


IMG_1937.jpg
 

Rocoa

Well-Known Member
Oct 17, 2018
102
64
95
Spain
Hello Shakti,

I'm enjoying a Corus and Aeris plugged to the PSU + Model 625 PSU. I've owned Synergy IIi with batteries of Model 6 too.
The system with the new PSU (supercapacitors) improves the performance of DAC and preamp a lot.
Cheers
 

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
The system with the new PSU (supercapacitors) improves the performance of DAC and preamp a lot.
Cheers

I definitely have to give the Conductor Phono a try, that would be than also the best chance to connect the Corus and the Conductor to the PSU !
 

Rocoa

Well-Known Member
Oct 17, 2018
102
64
95
Spain
I definitely have to give the Conductor Phono a try, that would be than also the best chance to connect the Corus and the Conductor to the PSU !
It's a good idea. I don't have phono preamp but some friends utilize it and with the PSU sounds fantastic. I must prevent you that, as all Rowland gear, the burn in time is very, very long. I don't know if it is due to the transformers, ceramic circuits or something else but it's so.
With this new PSU the sound is faster than with batteries. With batteries perhaps the sound seems more organic.
FYI, I'm using Nordost QKore 1 and QKore 3 since two weeks ago and it improves the sound of my system the way they proclaim.
 

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
I don't know if it is due to the transformers, ceramic circuits or something else but it's so.

The Lundahl transformers are known for very long burn in times. The JRDG stuff has the long burn in time since many years; to my knowledge even before the introduction of the ceramic boards.
One reason more for me to like used JRDG gear :)
 
  • Like
Reactions: Lagonda

Rocoa

Well-Known Member
Oct 17, 2018
102
64
95
Spain
The Lundahl transformers are known for very long burn in times. The JRDG stuff has the long burn in time since many years; to my knowledge even before the introduction of the ceramic boards.
One reason more for me to like used JRDG gear :)

Yes, after having owned and burned many Rowland gear for 30 years I think so:)
 

Lagonda

VIP/Donor
Feb 4, 2014
2,533
2,947
730
Denmark
Some of the most beautiful gear made ! The earlier models where always voiced
a little to warm for my taste, like he was trying make SS sound like tubes a little to hard. I must give newer models a try. Nice write up Jürgen. Congratulations
 

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
The Jeff Rowland Criterion uses 6 Batteries in the BPS. As with all Batteries, they do age. My Criterion has only a view playing hours, as bought from the former German Distributors Stock, so the batteries were working well.

But due to potential aging, I bought 6 new batteries (like 40,-eur) and exchanged them today.

This is done in 2 minutes from the outside, so not to compare with the work of exchanging Coherence II batteries, what I have done twice.

The effect of the new batteries is much bigger than thought. The old batteries did their hours playtime without charging as specified. But the new batteries have an immediate effect on the performance. Indeed, I can say, that Criterion plays more powerful. But even more important, the overall resolution and precision has increased significantly.

I am not sure, if the brand of batteries used can make a difference in performance. I bought the batteries just online.

The orginal JRDG batteries are unbranded OEM part with 9000 mAh (each batterie).

It seems, that he technology has developed in the last years, so the actual spec of this batteries are specified mostly as 10.000 mAh (with min 9.000 mAh). The total difference with 6 batteries is 6000 mAh, which is like 11% more current, if needed. The newer types of this batteries are saying, the they have a very low internal impedance, so I assume, that this might help as well to understand the difference , apart from just being old versus new batteries.

Realizing the price / effect ratio, I am ging to the batterie change now on an annual base.

(to avoid questions on that topic...: the batteries bought are exactly the NIMH 1,2v types specified from JRDG)
 

gfroman

Well-Known Member
Dec 29, 2012
370
433
305
Shakti -
Nice System!

This year I added the Rowland 925 amps, utilizing my EMM Labs DV2 as both preamp/DA direct to amps.
DV2 direct to the Rowland 925's via the High Fidelity - Ultimate Reference XLR cables.
DV2 has a Purist Audio Design - Diamond Dominus power cord.
Amps have (2) High Fidelity - PRO power cords.
Just stunning resolution and spooky imaging!!
 

Attachments

  • System19cc.jpg
    System19cc.jpg
    1.6 MB · Views: 58
  • Like
Reactions: RussR

edwyun

Well-Known Member
Feb 27, 2019
26
16
68
42
Nice JRDG history there. I didn't know the Syngery 2i could work wit the BPS6 (I thought it only worked with the BPS2). Is there any difference between them?
 

Rocoa

Well-Known Member
Oct 17, 2018
102
64
95
Spain
Hello,

It doesn't work with the BPS6 but Jeff made some adaptations with a external module to connect a BPS6 and feed the original Synergy PSU with batteries.
I've owned it for many years after my actual Corus with supercapacitors PSU and liked the performance.
 

Attachments

  • Imagen 1.png
    Imagen 1.png
    1.1 MB · Views: 34
  • Like
Reactions: ddk

edwyun

Well-Known Member
Feb 27, 2019
26
16
68
42
Thanks for the photo. Ive been looking for a bps2 for my synergy 2i. Kinda like trying to find hen's teeth. I assume it makes a noticeable difference (as I have heard others state with the Corus/PSU).
 

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
Thanks for the photo. Ive been looking for a bps2 for my synergy 2i. Kinda like trying to find hen's teeth. I assume it makes a noticeable difference (as I have heard others state with the Corus/PSU).

Just ask Jeff himself.
As he is customizing some of his older amps to new switch mode PSU, he might has a BPS available.
He also might sell the needed customization box for the Synergy directly, as this a very old models.
 

edwyun

Well-Known Member
Feb 27, 2019
26
16
68
42
Just ask Jeff himself.
As he is customizing some of his older amps to new switch mode PSU, he might has a BPS available.
He also might sell the needed customization box for the Synergy directly, as this a very old models.

Actually, I did ask Jeff a while back. The answer was, no. I could go to the Corus with PSU but then I would lose the mono toggle on the Synergy 2i, which I really like for the few mono LPs I have.
 

bryans

VIP/Donor
Dec 26, 2017
408
269
195
Great write up. I'm also a huge Rowland fan having owned too many JRDG products to list. I'm starting to look at a return to Rowland after years of trying different products. Most likely look to pick up a used Corus and 625S2. Now a 725S2 or above would be killer :cool:
 

Rocoa

Well-Known Member
Oct 17, 2018
102
64
95
Spain
Great write up. I'm also a huge Rowland fan having owned too many JRDG products to list. I'm starting to look at a return to Rowland after years of trying different products. Most likely look to pick up a used Corus and 625S2. Now a 725S2 or above would be killer :cool:

Don't forget the Corus PSU. It transforms the preamp.;)
 

shakti

Well-Known Member
May 9, 2015
1,150
1,554
330
Cologne, Germany
this is a double post (original posted in my Avalon Osiris thread),
but as the story relates to both threads:


Searching for a second Rowland M825 was faster achieved, then I guessed.

Found a very nice one in the Dutch neighborhood and picked up on Friday morning.

My Critical Mass Systems Maxxum base is exactly 80cm wide, so that the 39.5cm wide M825 fit right next to each other on this base.

I will operate the two Jeff Rowland M825s in vertical bi-amping,
ie assign one power amplifier to the right and one to the left channel. So I hope for an optimal channel separation.

Between the power amplifiers and the CMS Maxxum base I use the Nordost / Aavik pulsar points in aluminum.
They work quite well for now, let's see, maybe I'll try the current versions in the future

I had to come up with something when connecting the speaker cables.
The upper crossover has 4 inputs and the crossover for the bass corresponds to 1 input.

If you have a triwiring and a biwiring cable, everything works quite well if you connect the speakers to one stereo power amplifier, or two mono amps . But with 4 power amplifier channels it becomes a bit more complex because the power amplifiers should see a suitable load and I want to separate the bass area from the mid-high range drivers.

Accordingly, I have now connected the bass channel in single wiring mode (and thus disconnected the high out of the MIT cable) and given the super tweeter a Silentwire cable bridge instead.

The upper loudspeaker module and the bass module now have separate power amplifier channels.

Thanks to this separation, it is now also feasible to take advantage of the possibilities of the JRDG Criterion prepress. The second output stage (in my case the mid-high range is connected here) can be set separately in Volume as a preset .

After the technical function check, I listened to a few well-known pieces.

With these I had adjusted the Osiris in advance in the room so that the sonic touch of the pieces were well in my ears.

The first tonal difference I noticed was a "softer" and "cleaner" sound, don't know exactly how to describe it, the music just sounds more relaxed and more "natural". Playback is more relaxed overall.

The Avalon Osiris seems to like the double power in terms of performance,
and the separation of the two loudspeaker areas probably also helps.

The separation of the right and left power amplifier channel (the vertical BiAmping) leads in any case to a somewhat more precise and sharper outline of vocals and instruments

But at this point there is less sound improvement happening than I have been able to get to know with other bi-amping approaches. Obviously, a single M825 is already playing close to what is technically possible, so a double M 825 does not mean a double effect in performance

Now it was time to use the possibilities of the Rowland Criterion Preamp. And so I turned the MHT module up and down. With these changes you can change the sound character of the Osiris in fine gradations, my current listening taste means that I can now hear the Osiris with about 1db raised Mid- High driver level.

It is quite possible that this is due to the transition from the Maxx 3 to the Avalon Osiris,
the Osiris has a slightly more sloping frequency response than the Maxx 3.
With + 1db I can minimize this difference a bit.

Time will tell in which direction I go, for now this sounds very promising with this attitude.

IMG_3594.jpg IMG_3592.jpg IMG_3593.jpg
 

Alrainbow

Well-Known Member
Dec 12, 2013
2,456
923
385
NYC , USA
Shakti ,

How do these New Rowlands differ from say JR earlier stuff like model 9 et al ..
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing