Distortion with ARC Ref 150 and Maggie 3.7

Just read the last 5 or 6 posts. I posted a few comments a while back. Two points.

First -- Yes ... it is true. The ARC Ref 150, and presumably Ref 250, are designed to accept only a balanced (XLR) inputs. Not an SE (RCA) type. If you can rig some contraption to somehow do an end-run ... all the power to you. I own an ARC Ref 150. The last thought that would come to my mind would be to jury-rig (sp?) that type (or any type) of similar gizmo.

Second -- I've said this before and I'll repeat it once again. Maggies are power hogs.

I think Maggie 3.7s deserve a lot more juice than the Ref 150 can deliver. I'm sure the Ref 150 can drive the Maggies to an "ok" SPL, but not to the point where the 3.7s will open up and sound their best. I seem to recall that many years back, I had a similar conversation with either Len or Kal at ARC. They expressed similar views.

Bruce (Bifwynne), I wouldn't consider the use of a Jensen transformer to be a jury rig/jerry rig/kludge (whichever terminology one prefers). It's a legitimate means of converting a single-ended signal to a true balanced signal pair.

Consider also that some extremely highly regarded preamps have transformer-coupled outputs, and in some cases also utilize transformer coupling in their internal signal paths. Examples include the Coincident Statement line stage, and some ultra-expensive Audio Note models.

Of course, all transformers are not created equal. But the Jensen transformers are well regarded, and as I've indicated multiple times in this thread, a number of highly experienced members here who have very high quality systems have reported excellent results with it. And the OP was quite happy with the results he was getting with it, until an unrelated problem he experienced caused the thread to be resurrected, and various subsequent responses unrelated to that problem caused him to become concerned about theoretical issues that may or may not be subjectively significant, or even perceptible, in his system.

Regarding your other comment, I don't doubt that for some and perhaps many listeners the Ref 150's power capability may be marginal with the Maggie 3.7, and in fact that very issue is being discussed in another current thread you are participating in. Of course, the degree to which that may be a concern will depend on the particular listener's preferred volume levels, on the dynamic range of the recordings that are listened to (well recorded minimally compressed classical symphonic music perhaps being the worst case), and on listening distance and room size.

My impression, however (derived in part from your comments in other threads), is that the power supply of the Ref 150 is robustly designed, including large amounts of energy storage. Which, together with your comments about its marginality with the particular speakers, reinforces the concern I expressed in my previous post about the adequacy of the lower power rating (100 watts) of the CAT JL5.

Onhwy61, I'm surprised at your response to what I thought was a knowledgeable and entirely appropriate input from Knghifi. I would especially not have expected such a response from you in particular.

Best regards,
-- Al

Thanks Al. I take your point about using a transformer to connect an SE output to an XLR input. As I have admitted many times, I am not a EE-type, so the theory and application is way north of my pay grade. I suppose I am just biased (pun) about inserting artifacts into the signal path.

You may properly ask why, if I really feel that way, did I insert a DEQX digital time and EQ correction device in between my linestage and amp? My response: perceived sonic cost versus perceived sonic benefit. So far, I believe the latter significantly outweighs the former, ... I hope and think?????

Thanks for the electronics lesson. :)

Almarg, we will have to disagree about how appropriate, or more importantly, how helpful someone's recent comments on this thread have been. So many people have offered advice and guidance trying to solve the OP's situation. I didn't see the point of chiding or berating him. When I did the same thing to that poster, not surprisingly he didn't like it. Was what I did petty? Borderline. However,

This is an open forum and I'm contributing my .02.

I admit that I didn't do enough research before buying a balanced only amp for my single ended only preamp. So I'm the one that should be blame. However, it's a rare case when an adapter cable couldn't solve the connection problem. Anyway, I hope the negative comments on ARC shall end now.

Al, I didn't have the chance to audition the JL5 with my system. But I have friend whom I can trust to build confidence on the CAT amp. I only have moderate size room(10'x14x'17') and didn't go for high SPL while listening, so I think the 100 watts JL5 is good enough. I'll still keep the Ref 150 for comparison. If the Ref 150 is superior to the JL5, I don't worry about selling it as I bought with good price and there are plenty of CAT's fan down here. Perhaps I have same "problem" as Bifwynne, just don't feel comfortable with something else in the signal path!

Best regards,
Pakwong