RE: 45 amp and 95db speakers

Posted by Larry I (A) on April 1, 2015 at 05:53:10

In Reply to: 45 amp and 95db speakers posted by sam@edelmannpgh.us on March 29, 2015 at 16:21:40:

First, is this a 45 single-ended amp or a pushpull 45? For single-ended amps, the 45 is ideally used with very efficient and easy to drive speakers. For a 95db efficient speaker, A LOT depends on how easy it is to drive the speaker. There are quite a number of speakers rated (by the manufacturer) in that range that are really quite difficult even for much higher powered tube amps (e.g., Wilson speakers). These speakers tend to have an impedance curve that drops quite low at frequencies where there is a lot of demand for power. Also, because of the nature of the load (the speaker), the delivery of power and current are not in phase and the difference varies with frequency. If there is a big difference (measured as phase angle) at a frequency that demands a lot of power in music, that makes for a difficult speaker to drive. Hence, any two 95 db/watt speaker can be wildly different in terms of suitability.

I would guess that even an easy to drive 95 db/watt speaker would only be suitable for listening at modest levels in a smaller room with a single ended 45 amp; even a pushpull amp would be quite iffy with 45s. I own a pushpull 45 amp that I have used with an easy to drive 99 db/watt pair of speakers and some slight compression of dynamics on classical music with sustained loud passages (particularly choral music) is slightly noticeable.

It is unfortunate that this tube is so low powred because it does sound fantastic. I do like it more than I do the 300b and 2a3.

This post is made possible by the generous support of people like you and our sponsors:

Follow Ups Full Thread

Topic - 45 amp and 95db speakers - sam@edelmannpgh.us 16:21:40 03/29/15 (27)

Orgue Diatone Reissues? - David Lawrence 13:44:46 04/07/15 (0)

I wonder... - djk 23:06:17 04/05/15 (15)

RE: I wonder... - Tre' 08:28:25 04/06/15 (14)

RE: I wonder... - tomservo 09:42:15 04/07/15 (10)

RE: I wonder... - Tre' 11:48:47 04/07/15 (9)

RE: I wonder... - thetubeguy1954 23:17:47 04/10/15 (0)

RE: I wonder... - tomservo 13:18:08 04/07/15 (7)

RE: I wonder... - Tre' 16:35:20 04/07/15 (1)

RE: I wonder... - tomservo 06:24:25 04/08/15 (0)

RE: I wonder... - claudej1@aol.com 13:41:57 04/07/15 (4)

RE: I wonder... - tomservo 06:26:30 04/08/15 (3)

RE: I wonder... - claudej1@aol.com 06:59:23 04/08/15 (2)

Boy, did I get a reminder of that last weekend! - jusbe 20:44:52 04/22/15 (0)

RE: I wonder... - thetubeguy1954 23:29:16 04/10/15 (0)

RE: I wonder... - djk 15:38:48 04/06/15 (2)

RE: I wonder... - Tre' 20:20:52 04/06/15 (1)

OSHA - djk 00:55:02 04/07/15 (0)

RE: 45 amp and 95db speakers - Larry I 05:53:10 04/01/15 (1)

RE: 45 amp and 95db speakers - hvbias 19:44:55 04/03/15 (0)

RE: 45 amp and 95db speakers - vinnie2 05:19:50 03/30/15 (0)

RE: 45 amp and 95db speakers - Paul Joppa 19:49:38 03/29/15 (6)

RE: Amplifier power in dB Watts - BigguyinATL 13:25:32 03/31/15 (0)

RE: 45 amp and 95db speakers - sam@edelmannpgh.us 04:03:00 03/30/15 (4)

RE: 45 amp and 95db speakers - Jim D. 09:11:02 03/31/15 (2)

RE: 45 amp and 95db speakers - Paul Joppa 12:56:23 03/31/15 (1)

RE: 45 amp and 95db speakers - Saturntube 14:54:30 03/31/15 (0)

RE: 45 amp and 95db speakers - b.l.zeebub 06:29:58 03/30/15 (0)

Follow Ups

RE: 45 amp and 95db speakers - Larry I 05:53:10 04/01/15 (1)

RE: 45 amp and 95db speakers - hvbias 19:44:55 04/03/15 (0)

Post a Message!