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.

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.