ARC Ref 6 with Jeff Rowland Amps

[trponhunter]

the best pre amp is no pre amp - at least regarding an analog pre amp in a digital only system. Buy a trinnov amethyst or deqx - either one will beat either analog pre amp in terms of transparency.

[tdimler]

I am a big fan of Rowland electronics...I have a JRDG 625 S2 amplifier. I wouldn't steer you away from the Corus as it is a fine piece but said to be much better with the new Rowland PSU, though that is another big expense. I'd personally love to have a Ref 6 in my system but it is disqualified based on one factor that hasn't been mentioned here. The Ref 6 is incompatible with most sub-woofers due to an impedance mismatch. I see you have JL 212's. The F212 V1 has an input impedance of 10K ohms....this makes it incompatible with ARC pre-amps due to their minimum input impedance of 20K ohms. The only possibility of success is if you have the 212 V2 where they have raised the input impedance on single ended connections to 50K ohms to specifically deal with this issue. Even if you have the V2, it is worth looking at the total input impedance from two subwoofers and your amps as there is a compounded effect but I can't recall how to calculate that total figure.

The fact that ARC has eliminated most customers who drive a sub-woofer via their pre-amp seems like a poor decision.

Another thing to consider about the REF 6 is the issue of the acrylic top "melting". I can't fathom why they would not use a glass top or something more heat resistant on a pre-amp of this caliber.

[gadawg]

Originally Posted by tdimler

I am a big fan of Rowland electronics...I have a JRDG 625 S2 amplifier. I wouldn't steer you away from the Corus as it is a fine piece but said to be much better with the new Rowland PSU, though that is another big expense. I'd personally love to have a Ref 6 in my system but it is disqualified based on one factor that hasn't been mentioned here. The Ref 6 is incompatible with most sub-woofers due to an impedance mismatch. I see you have JL 212's. The F212 V1 has an input impedance of 10K ohms....this makes it incompatible with ARC pre-amps due to their minimum input impedance of 20K ohms. The only possibility of success is if you have the 212 V2 where they have raised the input impedance on single ended connections to 50K ohms to specifically deal with this issue. Even if you have the V2, it is worth looking at the total input impedance from two subwoofers and your amps as there is a compounded effect but I can't recall how to calculate that total figure.

The fact that ARC has eliminated most customers who drive a sub-woofer via their pre-amp seems like a poor decision.

Another thing to consider about the REF 6 is the issue of the acrylic top "melting". I can't fathom why they would not use a glass top or something more heat resistant on a pre-amp of this caliber.

Unfortunately a very good and valid point on the sub which keeps it out of many systems mine included. Wish the Output impedance on the Ref 6 was lower. Maybe on the Ref6SE?

[trponhunter]

I didn't notice that you also had subs - even more reason to get a trinnov , so you can properly cross them over and time align them. Running them the traditional way many people do with traditional analog pre amps with the main speakers being full range and adding the subs is not close to doing it properly crossed over.

[PlanarSpeakerFan]

Originally Posted by tdimler

Another thing to consider about the REF 6 is the issue of the acrylic top "melting". I can't fathom why they would not use a glass top or something more heat resistant on a pre-amp of this caliber.

A metal cover is available from ARC for the REF6 that looks and works great.

Ken

[PlanarSpeakerFan]

Originally Posted by tima

I've also had several pass through my listening room. Perhaps your experience is unusual. Mine says ARC gear has very broad compatibility with other manufacturers; Mcintosh being the prime exception. A quick look through one thread in this Audio Research forum finds people expressing satisfaction using a variety of ARC preamps with these amplifiers:

Moon W7M
Pass X350.5
Constellation Centaur Mono
Bryston 14BST
Atma-Sphere M60
Krell Evo amps
Accuphase Class A amp
Krell 750mcx monoblocks
Ayre MX-R mono blocks
Pass Labs Xs150
Threshold T-50 amps
GAS Son of Ampzilla
Gryphon Memphisto
Behringer DCX2496
Lamm M1.2
Pass XA160.5
Krell 302e
Classe 70 amp
Pass XA30.8
Atma-Sphere MA-1
Bryston 2.5 amp
Mark Levinson Class A
Ayre VX5
D'Agostino Momentum amps
Hypex Ncore NC400 monos
Bob Carver Sunfire Cinema Grand
Vandersteen M7-HPA mono amplifiers
Plinius SA-250 MKII amplifier

Excellent post, Tima! Thanks for including my Vandersteen M7-HPA monoblocks on your list! I’m in love with the sound of the REF10/M7-HPA combo. Substantially better in my opinion than the all VTL / Vandersteen 7 Mk2 system at RMAF that was voted best in show by several reviewers. I spent a lot of time in the Vandersteen room at RMAF this year.

Best,
Ken

[kaarmstrong]

Originally Posted by tdimler

I am a big fan of Rowland electronics...I have a JRDG 625 S2 amplifier. I wouldn't steer you away from the Corus as it is a fine piece but said to be much better with the new Rowland PSU, though that is another big expense. I'd personally love to have a Ref 6 in my system but it is disqualified based on one factor that hasn't been mentioned here. The Ref 6 is incompatible with most sub-woofers due to an impedance mismatch. I see you have JL 212's. The F212 V1 has an input impedance of 10K ohms....this makes it incompatible with ARC pre-amps due to their minimum input impedance of 20K ohms. The only possibility of success is if you have the 212 V2 where they have raised the input impedance on single ended connections to 50K ohms to specifically deal with this issue. Even if you have the V2, it is worth looking at the total input impedance from two subwoofers and your amps as there is a compounded effect but I can't recall how to calculate that total figure.

The fact that ARC has eliminated most customers who drive a sub-woofer via their pre-amp seems like a poor decision.

Another thing to consider about the REF 6 is the issue of the acrylic top "melting". I can't fathom why they would not use a glass top or something more heat resistant on a pre-amp of this caliber.

Tdimer, thank you for mentioning the concern with the subwoofers. I considered this aswell and this made me realize I left out an important piece of info, I am using a JLAudio CR-1 crossover to integrate the subs. The CR-1 has an input impedance of 20k ohm for balance and 50k ohm for unbalanced. I current use balanced ICs. So I was thinking the Ref 6 would still work. Do you think it is still a concern? Thank you.

Originally Posted by tdimler

I am a big fan of Rowland electronics...I have a JRDG 625 S2 amplifier. I wouldn't steer you away from the Corus as it is a fine piece but said to be much better with the new Rowland PSU, though that is another big expense. I'd personally love to have a Ref 6 in my system but it is disqualified based on one factor that hasn't been mentioned here. The Ref 6 is incompatible with most sub-woofers due to an impedance mismatch. I see you have JL 212's. The F212 V1 has an input impedance of 10K ohms....this makes it incompatible with ARC pre-amps due to their minimum input impedance of 20K ohms. The only possibility of success is if you have the 212 V2 where they have raised the input impedance on single ended connections to 50K ohms to specifically deal with this issue. Even if you have the V2, it is worth looking at the total input impedance from two subwoofers and your amps as there is a compounded effect but I can't recall how to calculate that total figure.

The fact that ARC has eliminated most customers who drive a sub-woofer via their pre-amp seems like a poor decision.

Another thing to consider about the REF 6 is the issue of the acrylic top "melting". I can't fathom why they would not use a glass top or something more heat resistant on a pre-amp of this caliber.

[gadawg]

If you use the single ended inputs into the crossover then considering the amps are 40K ohms and the SE input is 50k ohms then the preamp would effectively see 22k ohms which is the minimum ARC recommends. I would want to try it first for sure.

George

[PHC1]

What some tend to overlook or not be aware of is that there is such a concept of a "sweet spot" in the operating parameters of any gain/amplification device, be it a tube a JFET a MOSFET, etc. Just like in the story of Goldilocks and three bears, the sonic porridge can be too hot, too cold or just right. Or in automotive terms, being in the right gear for the optimal RPM and power output of the engine for the speed. Any gain/amplification device likes a particular "operating range", "temperature" and current where it is performing best or more importantly for our topic, sounds GOOD. Most manufacturers who are worth their salt "voice" their products and it would make sense to voice them together because a client/customer would likely use them together.

Way too much to type here but this all has to do with Voltage Gain, Input sensitivity, Preamplifier Vrms out and yes, impedance and capacitance besides other issues that come up such as a speaker load, your room and levels at which you drive your amplifier and speaker.

I am not going to post any links as that may violate forum rules but feel free to Google topics such as "Amplifier Voltage Gain Explained-Matching Preamplifier to Amplifier"

Nelson Pass "The Sweet Spot" article for those more technically inclined.

Showing us a list of members with a particular preamp in combination with a few dozen various amplifiers is not exactly a confirmation of good results as we all have our taste and understanding of what GOOD SOUND is. It is no different than me telling you that vinegar and mustard makes great steak sauce just because I tried it and it is edible. You should get sound out of any COMBO or preamplifier to amplifier but WILL IT SOUND GREAT? Will the gain device be in the sweet spot? Odds are it may and then there are cases where it isn't and the sound is not as great as it can be. Feel free to experiment away.

[PHC1]

Here is a prime example. My own system from the past. ARC Reference 40 preamp, 250 amps driving Tannoy Canterbury SE speakers. The 96dB efficiency of the Tannoy speakers did not work to the ARC 250 advantage. They were barely cruising along and not what I would consider The Sweet Spot". This ARC combo sounded much better when it was driving a tougher load like Wilson speakers. The Canterbury SE speaker came alive with the 10w flea powered Shindo SET amp because the Shindo was in the Sweet Spot.

Oh yeah, I got sound but was is it GREAT? NO! I sold that ARC combo to a friend who had Wilson speakers as he would be able to enjoy it much more than I could with my Tannoy at the time. Putting this combo in my other theater room with Wilson speakers was not practical at the time.

https://www.youtube.com/watch?v=7HiS4a-TcAU