Hi 94968, I own a pair of JRDG 7Ms which I dearly love. I confess of being a great fan of Jeff's current 312 design, which is currently my favorite amp. Soundings of Denver (Co) told me that Jeff has just introduced an external device containing the same Power Factor Correction circuitry found in the 312. It is said to bring a 501 close to the level of the 312. eHave you thought of applying it to your 7Ms? Or does your modification already include Power correction logic. I believe the device may be called PC1 with a retaile price of $1200.
Jeff Rowland Model 7 & Model 5 Upgrade
This is my first, and long overdue, post on the forum boards so please bear with me. Wanted to let everyone know that there is a substantial upgrade available for owners of the JRDG Model 7 and Model 5 amplifiers.
Briefly, I purchased my Model 7's a little more than 3 years ago and was amazed at the sound. Then one night one of the amps died. Basically something went very wrong inside and it became so hot you could not touch it. Yes, these amps will run quite warm normally, but this was smoking hot.
Next day spoke with Jeff directly about the amps and after some fact checking and trouble shooting we discussed the possiblity of upgrading the amps. This was something he had been wanting to do for the Model 7 and Model 5 amps for some time. We discussed ICE technology, as this was the time of the TAS review, and I also had long discussions with the audio store where I had made most of my purchases. After some considerable thought decided to pull the trigger. Shipped them off to Colorado, in the original crates, and waited for their return.
In my discussions with Jeff we decided to leave the power transformers in them to filter the ac and Jeff basically completely gutted the amps and put all new technology in them. I have before and after photos that I would be willing to share with anyone but do not know how to post them to this site. The whole process took about 4 plus months as these were the first amps to undergo the upgrade and Jeff had to create everything from scratch.
Finally got the amplifiers back around Christmas 2006. Jeff even called the day I brought them home to see what I thought, I informed him I was just in the process of unpacking them.
Now to the specifics. With the upgrade there is a 5 year warranty, they shed about 20 lbs. and now weigh in at a little more than 100 lbs each with balanced inputs. Power is conservately rated at 600 watts at 8 ohms, 1200 watts at 4 ohms. They are in a constant "on" mode and never get warm to the touch. Basically they are the new 501's in a Model 7 body.
Now to the sound. After a year of listening to them all I can say is Marvelous!!! I am not an audio writer but will try to convey the difference and improvements as best I can. In a word "Articulation". They have not lost their midrange warmth, but have improved upon it. It is more open, less tube sounding. Instruments are better defined, but not harsh or edgey. The soundstage is better delineated.
Part of the reason for not writing this sooner is because I was making numerous changes and upgrades to my system. It is now basically set for some time to come and consists of the following:
JRDG Coherence I Preamp (updated), Clearaudio Maximum Solution, Graham 2.3 tonearm, Benz Micro M2, Brinkman Phono amp, JVC XL1010 CD Player, Otari MX 5050 4 track R2R, Sonus Faber Guarneri Memento speakers, Siltech SQ110 interconnects with SATT, Siltech Power Cords, Siltech Emperor with SATT speaker cables.
I want to publicly thank Jeff Rowland for all of his help in this process, and apologize for not writing this sooner. It is extremely rare in todays business world to come across a company like JRDG, let alone its founder, designer, and owner to spend the kind of time he did on this project. It truely speaks for his passion of audio and improving his designs.
Finally, I am not an employee or in anyway associated/affiliated with the JRDG. I am just an audio enthusist like everyone else that visits this site and would highly recommend this upgrade to any owner of the Model 7 or Model 5 amplifiers.
Briefly, I purchased my Model 7's a little more than 3 years ago and was amazed at the sound. Then one night one of the amps died. Basically something went very wrong inside and it became so hot you could not touch it. Yes, these amps will run quite warm normally, but this was smoking hot.
Next day spoke with Jeff directly about the amps and after some fact checking and trouble shooting we discussed the possiblity of upgrading the amps. This was something he had been wanting to do for the Model 7 and Model 5 amps for some time. We discussed ICE technology, as this was the time of the TAS review, and I also had long discussions with the audio store where I had made most of my purchases. After some considerable thought decided to pull the trigger. Shipped them off to Colorado, in the original crates, and waited for their return.
In my discussions with Jeff we decided to leave the power transformers in them to filter the ac and Jeff basically completely gutted the amps and put all new technology in them. I have before and after photos that I would be willing to share with anyone but do not know how to post them to this site. The whole process took about 4 plus months as these were the first amps to undergo the upgrade and Jeff had to create everything from scratch.
Finally got the amplifiers back around Christmas 2006. Jeff even called the day I brought them home to see what I thought, I informed him I was just in the process of unpacking them.
Now to the specifics. With the upgrade there is a 5 year warranty, they shed about 20 lbs. and now weigh in at a little more than 100 lbs each with balanced inputs. Power is conservately rated at 600 watts at 8 ohms, 1200 watts at 4 ohms. They are in a constant "on" mode and never get warm to the touch. Basically they are the new 501's in a Model 7 body.
Now to the sound. After a year of listening to them all I can say is Marvelous!!! I am not an audio writer but will try to convey the difference and improvements as best I can. In a word "Articulation". They have not lost their midrange warmth, but have improved upon it. It is more open, less tube sounding. Instruments are better defined, but not harsh or edgey. The soundstage is better delineated.
Part of the reason for not writing this sooner is because I was making numerous changes and upgrades to my system. It is now basically set for some time to come and consists of the following:
JRDG Coherence I Preamp (updated), Clearaudio Maximum Solution, Graham 2.3 tonearm, Benz Micro M2, Brinkman Phono amp, JVC XL1010 CD Player, Otari MX 5050 4 track R2R, Sonus Faber Guarneri Memento speakers, Siltech SQ110 interconnects with SATT, Siltech Power Cords, Siltech Emperor with SATT speaker cables.
I want to publicly thank Jeff Rowland for all of his help in this process, and apologize for not writing this sooner. It is extremely rare in todays business world to come across a company like JRDG, let alone its founder, designer, and owner to spend the kind of time he did on this project. It truely speaks for his passion of audio and improving his designs.
Finally, I am not an employee or in anyway associated/affiliated with the JRDG. I am just an audio enthusist like everyone else that visits this site and would highly recommend this upgrade to any owner of the Model 7 or Model 5 amplifiers.