Jeff Rowland 625 amp ... & 725

Some months ago I was already positively impressed when I had the opportunity to compare the 312 (class D) to the new 625 (class AB) in the same system ...

today my dealer told me that Jeff Rowland has sent him a new "platine" (board in English?) to install into the 625 and that it is sounding even better

this upgrade seems to be free !

I am very looking forward to hear it and wondering how will be sounding the 725

Thanks for the heads up!
I just purchased a Rowland 625 here on Audiogon.
I'll contact JRDG & see if the board is available..
how is it working with the apogee ?

which lsp cables are you using ?
Very interesting Claude, I'll have to find out the scoop about the M625 update.... Next week after everyone comes back from CES in Vegas. G.
it PAINS me to ask this, but why all the MYSTERY behind the 725 mono blocks i see advertised, but not a clue about them on the JRDG web site, or anywhere else for that matter ('cept maybe a picture or two taken at an audio show). how about the BASICS, like cost, watts, when will they become available, have they shipped out some demo's to dealers, etc.? P.S.- i still have not learned to read reviews in Japanese.
No deliberate mysteries FrenchFries... It's just that web sites are always behind the proverbial eggball... M725 has started to ship in December 2011; Last I heard, price was $28K.... As for power rating, I will learn about it coming week, but I suspect it may be around 340W per side or so. Guido
$ 28 K ... this will be translated on this side of the atlantic in 35'000 €

a real pity !
The other side of the Atlantic will soon economically disappear so this is not a pity, this is irrelevant.
Inna, Claude lives on the other side of the Pond, hence his understandable Eurocentric concern. Guido
Well, I exaggerated a little but it's going to be tough over there. Not for everyone though, as always.

5 countries in Europe are still rated triple AAA by S&P
USA has already been downgraded

and look at the devaluation of the $ in foreign currency terms
1970 1$ = 5 SF
1980 1$ = 3,5 SF
1990 1$ = 2,5 SF
2000 1$ = 1,8 SF
2010 1$ = 1,1 SF

today 1$ = 0,95 SF after bouncing at 0,75 SF !!!

it seems to me that the western side of the pond has some problems too

these are facts
Sure, I agree. It's quite a mess here too. Dollar is now a "political currency", its real value is quite low. But euro's value is zero, no value at all. Unlike Swiss Franc.
CES présentation of the 725 ... but also of something new ?

the PSU power storage unit

what is it exactly ?

I still have my Sonus Faber Concerto Domus hooked up.
I need to rearrange my listening room for more space around my Apogee Stages...

Check out this site for the Rowland gear:
Claude, I believe that the new PSU Power Unit may be an external supercapacitor-based power supply that can be applied to deliver DC to Corus, Aeris, and the upcoming Criterion replacement. I do not have any details from JRDG, but knowing a little about supercapacitors, it is likely that PSU may yield a great deal of transient authority to applicable devices.

And just in case you were asking.... No, you can't apply PSU to any power amps.... Just not enough current for that.



click on the "CES" link

click on "amplifiers"

scroll down & you'll find pictures of the 625, 725,
and PSU.

the PSU is as large as a good sized preamp.

it will probably be expensive!
Looks like JRDG has finally posted M725 mono amp specs at:

Purely from memory.... 330W at 8 Ohms, 640 at 4 Ohms... 1500W power supply with PFC, ceramic boards, class A/B... no overall feedback.


640 at 4 Ohms... 1500W power supply with PFC

I don't understand ?

and PFC or PSU ?
Read knowledgebase at JRDG - Power Factor Correction.
Claude, the external PSU device cannot be applied to power amplifiers at all.... It was designed for low current applications only. It is currently compatible with Corus and Aeris. In the future, it will be compatible with the Criterion follow-on preamplifier.

M725 is powered by an internal high speed DC SMPS fed by a 1500W PFC unit, also internal to the M725 chassis.

And just in case anyone asked... No, PSU is absolutely NOT compatible with the now withdrawn Criterion or Capri any other preamplifier... If you ever managed to connect the two by some jerry-rigging, you will likely end up with cute little fireworks, followed by even cuter blue smoke, charming smell of singed circuits, and.... not so charming knashing of teeth (your own teeth, that is). G.
Hi Guido, was the RRP for the PSU confirmed? Also any indication from Jeff Rowland whether a Corus + PSU will match Criterion? Thanks Mark
Marc, as far as I know, the PSU unit shown in Vegas was an advanced prototype, not a full production unit... PSU has not been released. I have not heard of any price yet.

What I have heard about PSU is that it is a power supply based on supercapacitors instead of NiMH batteries. At least in theory, it should be capable of delivering quite a bit of authority, because supercaps are capable of very quick power surges, while NiMH batteries are not. But, until I hear the effect of PSU on a device myself, I will have no idea of what it really does for living in general, nor whether it lets Corus surpass Criterion in particular. G.
Guido, any news on the plans for a Criterion replacement? I thought that was pretty quick for JRDG to delete a statement model that fast. Also any news on JRDG phono preamp? With the resurgence of analog, I would think one might be in their future plans.

I'm sure you meant "Eightball" not "Eggball".
Hi Phil, I have no info on Phonostage projects at JRDG one way or another.

I know that a Criterion follow-on project is underway, but I do not know the exact release timeline. I suspect that the Criterion follow-on my utilize PSU for power supply. Guido
Oopsie Tab10s.... Sure thing.... should have been "eight-ball" not egg-ball. Afraid that English is not my mother tongue, as just transpired... On the other hand, I contend that playing pool with a fresh egg as ball number 8 should add an unexpected splattering fun factor to the old game *snickers! G.
Thank you for your responses Guido.