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Thanks Al. I really like the sound and built quality of Jeff Rowland amps. The truth is I've been going back and forth, asking questions and talking to a close friend about how to improve my system within a given budget. Adding subs has taken my system to another level(not night and day), but worth the cost. Now I'm looking for modest gains, with modest cost...my amplifier is what I want to improve. I hear your concerns about bridging the 525s. Despite what I've been told, I have the same concerns. I will have one more conversation with Jeff Rowland. |
Bombaywalla,
I assure you I know the impedance of my speakers. In fact I'm 100% sure I told that to the individual that I spoke with when I contacted Jeff Rowland. I didn't say at what frequency it dipped below 4 ohms, but I did explain it went below 4 ohms...they put me on hold, returned to the phone and told me it wouldn't be a problem. I talked to a dealer ad he told me it wouldn't be a problem. I promise you I'm listening and that's why I stated I would call Jeff Rowland on Monday and confirm that bridged 525s don't present a danger went driving Aerial 7Ts. If they tell me something different I will let you know.
Ricred1 cool, Ricred1. One suggestion - when you talk to Rowland the next time do request some specs of the M525 in BTL mode. All of us can see just one spec - 950W into 8 Ohms. The question is what is the minimum load impedance it can drive? The Aerial 7T will go down to 3 ohms at certain freq which will look like 1.5 Ohms to the bridged M525 (as Almarg also stated in his post). Ask Rowland if driving 1.5 Ohms in bridged mode will be an issue. Keep us posted. Thanks. |
Richard, if you ask the question above to Jeff, please explain that 7Ts speakers go down to a relatively reasonable 3 Ohms under normal conditions.... 1.5 Ohms may occur only in theory with a bridged amp... You do not want to lead Jeff to believe that your speakers dip normally to 1.5 Oh... Meaning a ghastly 0.75 Ohm from a bridged amp.
G. |
Guido is absolutely correct, he beat me to it in pointing that out. |
And the other question that comes to mind is, considering the low impedance of 7Ts....
Ask Jeff... What can be a more efficient combination for your speakers.....
* A Rowland M625 V1) with a theoretical damping factor of 200 across the board and approx 20A of peak current;
* A pair of bridged M525s;
* A pair of M525S in vertical biamped configuration?
NOTE. M625 S2 has a completely different cost, so I am not considering it in the discussion.
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06-14-15: Guidocorona
Richard, if you ask the question above to Jeff, please explain that 7Ts speakers go down to a relatively reasonable 3 Ohms under normal conditions.... 1.5 Ohms may occur only in theory with a bridged amp... You do not want to lead Jeff to believe that your speakers dip normally to 1.5 Oh... Meaning a ghastly 0.75 Ohm from a bridged amp.
G.
Guidocorona (Threads | Answers | This Thread)
06-14-15: Bill_k
Guido is absolutely correct, he beat me to it in pointing that out.
Guidocorona, Bill_k, my post made is very clear that the Aerial 7Ts were a min of 3 Ohms nomimal & 1.5 Ohms in bridged mode. This was very clearly written, no? I'm cutting & pasting that part of my post again for your resp. convenience.... The Aerial 7T will go down to 3 ohms at certain freq which will look like 1.5 Ohms to the bridged M525 (as Almarg also stated in his post). Ask Rowland if driving 1.5 Ohms in bridged mode will be an issue. |
Bombaywalla, yes, your post was absolutely wonderful... Tech credit is all yours. G. |
I will ask the question and post my response tomorrow. If cost wasn't a consideration I would purchase the 625 mk2. If I had the opportunity to listen to bridged 525s in my system, I wouldn't have posted the question. I know one person that utilizes bridged 525s to drive Avalon Speakers and loves it.
Why not the Continuum S2 integrated. I had the opportunity to compare an Esoteric K01 to the Bricasti M1. Music through the M1 had more detail, more musical, and just natural sounding. Remember I had a Parasound JC2 preamp and preferred music without it. I prefer my money go to improving the amplifier, without adding a preamp. Now if I can't use bridged 525s or can't find a used 625 that has the most recent updates, I may need to look at other options. |
Now if I can't use bridged 525s or can't find a used 625 that has the most recent updates, I may need to look at other options. Richard, to be sure it's clear, using two 525's in a vertical biamp configuration completely avoids the potential issue that has been raised about using bridged amps in conjunction with low impedance speakers. At the same time, it very likely would provide sonic benefits that would not occur in bridged mode, and I suspect would have no downside relative to bridged mode aside from probably having a bit less maximum power capability (although maximum power capability would still be significantly greater than what you have now). Good luck. Regards, -- Al |
Hi Richard, yes you are right... I was missing the obvious... From Bricast M1, it's probably a good idea to go directly into an amp via balanced XLR connections. This would be sub-optimal from Continnuum S2, because its linestage bypass inputs are single ended RCA, while CS2 architecture is optimized for a fully balanced signal path.
Guido |
Bombaywalla - Your post was factually correct, but I felt it could use some further clarification after you stated: "Ask Rowland if driving 1.5 Ohms in bridged mode will be an issue." I thought as Guido stated that this could be interpreted as if the speaker had a 1.5 Ohm nominal impedance instead of 3 Ohms. No offense was intended to you as your post was helpful and constructive. |
I talked to Lucien(Jeff Rowland Group) today regarding bridging the 525 to drive Aerial 7ts. Per our conversation, he discussed the issue with Mr. Jeff Rowland and they agreed that bridged 525s would have no problem driving Aerial 7Ts. I asked him if it were him, what would he do? I was surprised that he answered my question! His answer, "if you're comparing one 525 to a Continuum S2, get the Continuum; however bridged 525s with a Capri S2 preamp will beat the Continuum S2 integrated amp. |
What is the MSRP of a Capri S2 and two 525 amplifiers compared to that of a Continuum S2? |
Ricred1,
great! thanks for the update. looks like you are good to go w/ the M525. You now know that you won't have a melted output stage with the Aerial 7T's 1.5 ohms in bridged mode.
Still......I would give heed to Almarg's suggestion (which was also on my mind but Almarg beat me to it) of using 1 stereo M525 for each speaker in a vertical biamped format. The amp will not see 3 Ohms (because it will be running in plain old stereo mode) & you will have 1 dedicated amp for driving the bass for each channel.
Since you will have 2 M525s you can try the bridged mode & the vertical biamped mode. Yeah, you will need 4 interconnects pre-power & 4 speaker cables to try the vertical biamped mode.
Let us know how you fare. Thanks. |
+1 Bombaywalla (with a slight qualification as described below).
Richard, I see that you are using some rather expensive interconnects and speaker cables. In part for that reason I would reiterate my earlier comment to the effect that you wouldn't have to double up on interconnect cables to implement a vertical biamp configuration. You would just use a short XLR y-cable at the inputs of the amp, such as one of those I linked to earlier, in conjunction with the same interconnect you would use for bridged mode.
You may have seen people claim at times that use of y-cables or splitters in their system resulted in some amount of sonic degradation. My strong suspicion is that in most of those cases the reason for that was not the y-cables or splitters themselves, but rather the inability of the component supplying the signal to drive the two sets of load impedances that were involved, and in many cases two sets of cables as well, in an optimal manner. That won't be an issue in your situation.
For example, it is sometimes reported that poor results are obtained when a y-adapter or splitter is used to route the outputs of a preamp to both a power amp and a powered sub. In those situations it tends not to be realized that the capacitance of the cable to the sub, which is often substantial due to the length that may be involved, will affect the signals received by the main power amp just as if it were added to the capacitance of the cable to the main power amp. It also tends not to be realized that the line-level input impedance of many and probably most powered subs is quite low, which will also affect the signals seen by the main power amp, especially if the preamp's output impedance is high. Yet the y-adapter itself will often be blamed for the less than optimal results.
None of those kinds of effects will be applicable in your situation, given also that the RCA outputs of the Bricasti DAC, which I assume you are using to drive your subs, are driven by output stages that are fully independent of those driving the DAC's XLR outputs (that often not being the case with lesser designs).
Finally, the very low output impedance of the Bricasti DAC, the fact that its connections to the amps are balanced, and the relatively short lengths that are involved, all work in the direction of reducing sensitivity to interconnect cable effects and differences. Including the effects of balanced y-cables that may be in the path.
Regards,
-- Al
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Macro, here are list prices....
Capri Series II Stereo Preamplifier $3,950
Model 525 Stereo Power Amplifier $4,500
Continuum S2 integrated: $9500
Richard has indicated that he will be driving M525s directly from his Bricasti M1 DAC, sens line stage. G. |
I also agree with the vertical biamp recommendation. I do this in my own system and get great results. All you need are 2 stereo amps (exactly the same), and a pair of speakers with 2 sets of binding posts. You have both so its just a matter of making the connections and trying it out. I'm kind of surprised Rowland didn't mention this option when you called them. |
Zd542,
Rowland actually mentioned vertical biamp as an option. I had a long talk with them and this is what I have decided. I'm going to get a Continuum S2 Integrated(home audition) and see if there is a big enough difference between it and a single 525(525 already for sale). My concern is a degradation of the sound through the line stage compared to the Bricasti M1. "IF" what I read is true the Continuum maybe the least complicated and most cost effective way forward. If I don't think the Continuum is a big enough difference, I will sell my 525 and look for a used/demo 625 mk1. I just want to reiterate I really like Jeff Rowland's sound. |
I'm not trying to 2nd guess your decision, or anything like that. We're just recommending that if you have all the equipment already in your possession, you've got nothing to loose trying it both ways, vertical and bridged. Honestly, I can't say if the bridging will be an improvement. I've never bridged Rowland gear, so I'm looking forward to hearing your comments on how it sounds. The vertical will sound better than a single. The question is how much better, and is it worth it. That has to be your call. In my system, I have 2 Ayre V-5's running vertical, and I'm very happy with the results. |
If I don't think the Continuum is a big enough difference, I will sell my 525 and look for a used/demo 625 mk1.... +1 Almarg, Zd542. Ricred1, before you sell off your M525 in the event the Continuum integrated is not a major step-up in SQ, do try using your 2 M525s in a vertical biamp config. It might just surprise you SQ-wise - amps driving a higher impedance are generally less stressed & sound better, no matter what the manuf says. (There are a few expensive amps that buck this general trend but these are exceptions). If it doesn't, so be it, you tried/explored every configuration with all the Rowland gear you had on-hand & it did not work out so you decided to go for the M625 Mk1. Like Zd542 wrote - you have both M525s & all the cabling (if I understood Almarg's post correctly), it behooves you to try the vertical biamp config. thanks. |
I finally had the opportunity to compare the Continuum S2 to the M525 in my own system. I'm 100% sure going to purchase the Continuum S2. |
Congratulations Richard... Continuum S2 would have been my final choice as well! G. |
Guido,
I appreciate you sharing you time and knowledge regarding Jeff Rowland products. My situation was difficult because I wanted to hear the S2 in my system, but didn't want to feel obligated to purchase from the dealer that could make it happen. I had to wait until a friend of a friend could help me out. It's funny how we hear different things, you said the S2 was clearly better, while others thought the S2 was only marginally better. I know I can enjoy music with the S2 and not think about my next purchase. |
Pleasure is all mine Richard... Reality is that audible beauty lies in the ears of the beholder... And I suspect that you and I might be hearing in ways that are not dissimilar.
Undeniably, someone else,, equally passionate about audio and music, might have prefered M525... Or the house sound of a totally different brand.
Guido |
Guido,
I try hard to express my preferences while respecting other's points of view. Audio is definitely a preference, but not an absolute. I submit the M525 is great in a smaller system/room, but in my 20' x 26' room, combined with Aerial 7Ts the power and fidelity of the S2 is very obvious.
I submit the Bricasti M1 DAC is great, but knowing what I know now, if someone gave me a choice between having a PS DSD DAC with the JR Continuum S2 or Bricasti M1 DAC with the JR M525, I would take the former of the two. That speaks volumes to how good I think the Continuum S2 is compared to the M525. |
I had the chance to do a long side-by-side between the C500 and the S2. I used the same external DAC, cables and monitors with both. I alternated the monitors between the SF Amati Serafino, Maggie 3.7, and a pair of Shahinian Hawks. I must say it's really a toss, I expected the S2 to be better and it was at times, but not all the time. I think the Maggies overall sounded better with the C500, a better bass and midrange. The Shahinians sounded best with the S2, and it was a complete toss up with the Serafino's. I think the Serafinos are the least colored speakers of the bunch. All of the monitors present difficult loads to an amp. |
