FAQ  •  Register   •  Gallery •  Login

It is currently Sat Sep 20, 2014 5:02 pm

Carver PM 1.5 User-Adjustable Clip Limiter Function

<<

fhawk618

Newbie

Posts: 11

Joined: Sun Nov 28, 2010 6:54 am

Post Tue Nov 30, 2010 6:58 am

Carver PM 1.5 User-Adjustable Clip Limiter Function

I have a bunch of PM 1.5 amps that I use (as intended) for pro-audio/sound reinforcement applications. Recently, I acquired several amps that have user-adjustments for the clip limiter on the faceplate--something I have not encountered before. All PM 1.5s have a switch to defeat/apply the limiter fuction (with which I am familiar), but these also have two RMS Output Voltage adjustments--one for a 1.5 second limit value variable from 45 to 77 volts, and one for a 30 second limit value variable from 20 to 77 volts. I purchased these from the original owner, and he has no idea regarding their purpose/function; however, they are secured by lock-nuts from the factory and are still set at the original factory specifications. I've done some preliminary research (still looking) and the original Carver Service Manual states that these controls were only present on the "first 1000 or so built."

Any input would be greatly appreciated.
<<

engtaz

User avatar

"TAZ"

Posts: 5209

Joined: Sat Jun 30, 2007 1:43 pm

Location: Tampa, FL

Post Tue Nov 30, 2010 1:37 pm

Re: Carver PM 1.5 User-Adjustable Clip Limiter Function

Welcome
engtaz


Carver M4.0T in front channels to Caver AL VI's in SACD & 2 Channel setup
C 16, PT 2400, Slim Device, Carver TX-8, 490T and Rega TT w Grado Gold cart in the 2 channel setup
Bogen SRB20 is computer amp
Carver PM-350 donated for youth church use
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Tue Nov 30, 2010 3:15 pm

Re: Carver PM 1.5 User-Adjustable Clip Limiter Function

It appears from the description below that these functions restrict the RMS voltage output both short and long term. Their settings would be a function of the drivers you were using on their outputs. For instance, voice coils can sustain short term RMS voltage higher than long term (and they cool off in-between).

Image.jpg
Image.jpg (164.28 KiB) Viewed 827 times
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer
<<

fhawk618

Newbie

Posts: 11

Joined: Sun Nov 28, 2010 6:54 am

Post Wed Dec 01, 2010 5:52 pm

Re: Carver PM 1.5 User-Adjustable Clip Limiter Function

Thanks for the input, hoping for some more. BillD, that's exactly what I know about these controls so far, but the user manual and service manual stop there. I'm hoping to find out what impact any adjustments would have on loudspeaker or amplifier protection. It appears (to me) that these are intended more to gate the amp's maximum output level, since the output of these amps is very dynamic.
<<

BillD

User avatar

(pair of) SILVER-7 TUBE AMPs

Posts: 7295

Joined: Wed Jun 06, 2007 8:29 pm

Location: The west's most mid-western town, Scottsdale, Arizona

Post Wed Dec 01, 2010 7:35 pm

Re: Carver PM 1.5 User-Adjustable Clip Limiter Function

Well, logic would have it that you set the short term voltage to what you voice coils can handle short term (1½ seconds) and the long term voltage (30 seconds) to what your voice coils can take longer term. With the top rail at 124V, a 100Vrms sine wave can be accommodated without clipping. That's a lot of pressure into a voice coil. Apparently, these adjustments will also shut your amp down when the values you set are exceeded for those threshold times, even if the amp isn't clipping.

If you want to try them out, get yourself some dummy loads. Calrods or toasters work fine.
It should sound like it isn't there!
There is a difference between hearing and listening...
Making life enjoyable through expensive electronics.
_________________
Carver: C-4000 & C-1 preamps, PSC-60 preamp/tuner, TX-11a tuner, M-400 (2), C-500, M-500, M-500t, M-500t Mk.II, A-500x, AL-III loudspeakers (2 pr.)
Sunfire:Theater Grand III processor, Ultimate Receiver, Cinema Grand Signature 400 ~ seven, True Subwoofer Mk. II, D-10 Subwoofer
<<

fhawk618

Newbie

Posts: 11

Joined: Sun Nov 28, 2010 6:54 am

Post Wed Dec 01, 2010 7:49 pm

Re: Carver PM 1.5 User-Adjustable Clip Limiter Function

Thanks--makes sense to me. Now I just have to dig up the specs for the drivers in these cabinets to see what they're up for (after some testing first). It would seem that you could take fuller advantage of the amp's dynamic power based upon the driver's ability to handle the higher output voltage. I use primarily Peavey and EV cabinets/drivers which can take quite a beating. Seems you could also do some serious damage downstream if you got "heavy handed". Probably why those controls were deleted after the first production run of 1000 units.

Thank again!

Return to Carver Pro

Who is online

Users browsing this forum: No registered users and 0 guests

Powered by phpBB © 2011 phpBB Group.