Speakerplans.com Homepage
Forum Home Forum Home > General > Amp Forum
  New Posts New Posts RSS Feed - Amp Internals 2
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Amp Internals 2

 Post Reply Post Reply Page  <1 224225226227228 260>
Author
Message
 Rating: Topic Rating: 1 Votes, Average 5.00  Topic Search Topic Search  Topic Options Topic Options
kedwardsleisure View Drop Down
Old Croc
Old Croc


Joined: 20 January 2009
Location: Staffordshire
Status: Offline
Points: 4938
Post Options Post Options   Thanks (0) Thanks(0)   Quote kedwardsleisure Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2019 at 8:33am
Here's a Crown MA12000i that I had the opportunity to repair this week, pics are a bit blurry but I was having trouble containing my glee...











Kevin

North Staffordshire

Back to Top
Elliot Thompson View Drop Down
Old Croc
Old Croc
Avatar

Joined: 02 April 2004
Location: United States
Status: Offline
Points: 5172
Post Options Post Options   Thanks (0) Thanks(0)   Quote Elliot Thompson Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2019 at 5:46pm
Originally posted by kedwardsleisure kedwardsleisure wrote:

Here's a Crown MA12000i that I had the opportunity to repair this week, pics are a bit blurry but I was having trouble containing my glee...



Did you have the chance to bench test the amplifier?

Best Regards,
Elliot Thompson
Back to Top
kedwardsleisure View Drop Down
Old Croc
Old Croc


Joined: 20 January 2009
Location: Staffordshire
Status: Offline
Points: 4938
Post Options Post Options   Thanks (0) Thanks(0)   Quote kedwardsleisure Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2019 at 11:19pm
not exactly, I shoved it on the dummy load and got it nice and warm, you know, the mode where it sounds like a vacuum cleaner.



https://youtu.be/D40i8F6f9ls



On a pure sine wave input the limiter tends to pump as it approaches max output, I doubt this is likely in normal use.

Edited by kedwardsleisure - 19 July 2019 at 11:24pm
Kevin

North Staffordshire

Back to Top
Pinyorouk View Drop Down
Young Croc
Young Croc


Joined: 31 January 2011
Status: Offline
Points: 550
Post Options Post Options   Thanks (0) Thanks(0)   Quote Pinyorouk Quote  Post ReplyReply Direct Link To This Post Posted: 19 July 2019 at 11:56pm
Ken, you have no fear of things going bang 😃😃. 

Edited by Pinyorouk - 20 July 2019 at 7:25am
Back to Top
M4trix View Drop Down
Registered User
Registered User
Avatar

Joined: 23 June 2009
Location: Croatia
Status: Offline
Points: 445
Post Options Post Options   Thanks (0) Thanks(0)   Quote M4trix Quote  Post ReplyReply Direct Link To This Post Posted: 20 July 2019 at 12:00am
You're using a good old analog oscilloscope. Good. Not those digital rubbish. Thumbs Up 
Back to Top
Elliot Thompson View Drop Down
Old Croc
Old Croc
Avatar

Joined: 02 April 2004
Location: United States
Status: Offline
Points: 5172
Post Options Post Options   Thanks (0) Thanks(0)   Quote Elliot Thompson Quote  Post ReplyReply Direct Link To This Post Posted: 20 July 2019 at 12:33am
Originally posted by kedwardsleisure kedwardsleisure wrote:

not exactly, I shoved it on the dummy load and got it nice and warm, you know, the mode where it sounds like a vacuum cleaner.



https://youtu.be/D40i8F6f9ls



On a pure sine wave input the limiter tends to pump as it approaches max output, I doubt this is likely in normal use.


Thanks. That video answers more questions than you might imagine.


One of the things I've noticed about the second generation of Crown's Class I series is, greater stability under long-term conditions than, their first generation models. Your results of the Macro-Tech I 12000 are similar to DJ Leco benching the Macro-tech I 5000 in addition to the CTS 3000 from a longevity standpoint. The second generation I-Tech Series does not go into cardiac arrest like the first generation I-Tech Series.


This may be the reason why Crown literally abandoned the first generation I-Techs in terms of sending them back to their factory in order to have them repaired. Crown no longer offer parts for the first generation I-Techs, which led to a lot of used first generation I-Techs for sale on Ebay.


Best Regards,

Elliot Thompson
Back to Top
paulus View Drop Down
Old Croc
Old Croc
Avatar

Joined: 14 December 2005
Location: SOUTH BIRMINGHA
Status: Offline
Points: 3181
Post Options Post Options   Thanks (0) Thanks(0)   Quote paulus Quote  Post ReplyReply Direct Link To This Post Posted: 23 July 2019 at 12:18pm

old crest fa2401 gave it a clean out the weekend , super build quality !!


Edited by paulus - 23 July 2019 at 12:19pm
TRENDSETTER SOUND SYSTEM
Back to Top
U.Viktor View Drop Down
Young Croc
Young Croc


Joined: 04 May 2010
Status: Offline
Points: 716
Post Options Post Options   Thanks (0) Thanks(0)   Quote U.Viktor Quote  Post ReplyReply Direct Link To This Post Posted: 23 July 2019 at 1:09pm
Originally posted by kedwardsleisure kedwardsleisure wrote:

Here's a Crown MA12000i that I had the opportunity to repair this week, pics are a bit blurry but I was having trouble containing my glee...













Not only the 1st gen. is problematic from the I-techs. Despite the theoretically good and quality designed circuitry the actual realization of the amp has built-in disasters such as "critical function nodes" of the gate-driver boards across unreliable connectors.. When we went to Romania roads couple hundreds of kilometers, many of these amps has refused to work // starting uo, creating not a small problem for on site. :-(
Another problem is the too many ribbon cables and power supply sensitivity of overloading conditions.
Back to Top
Tonskulus View Drop Down
Registered User
Registered User


Joined: 15 September 2017
Location: Finland
Status: Offline
Points: 425
Post Options Post Options   Thanks (0) Thanks(0)   Quote Tonskulus Quote  Post ReplyReply Direct Link To This Post Posted: 23 July 2019 at 9:40pm
From Crown website (MA12000i): 
"Rugged construction ensures that all Macro-Techs are built to withstand years of abuse on the road"

Oh well.. :D


Back to Top
Meat View Drop Down
Old Croc
Old Croc


Joined: 05 June 2009
Location: Manc
Status: Offline
Points: 1514
Post Options Post Options   Thanks (0) Thanks(0)   Quote Meat Quote  Post ReplyReply Direct Link To This Post Posted: 23 July 2019 at 9:57pm
Designed for life on the road without corners.
Don't test the champignon sound
Back to Top
kedwardsleisure View Drop Down
Old Croc
Old Croc


Joined: 20 January 2009
Location: Staffordshire
Status: Offline
Points: 4938
Post Options Post Options   Thanks (0) Thanks(0)   Quote kedwardsleisure Quote  Post ReplyReply Direct Link To This Post Posted: 23 July 2019 at 10:49pm
this one's been toured for some years
Kevin

North Staffordshire

Back to Top
Chris Grimshaw View Drop Down
Registered User
Registered User


Joined: 10 September 2018
Location: Sheffield
Status: Offline
Points: 281
Post Options Post Options   Thanks (0) Thanks(0)   Quote Chris Grimshaw Quote  Post ReplyReply Direct Link To This Post Posted: 24 July 2019 at 8:40am
Originally posted by kedwardsleisure kedwardsleisure wrote:

not exactly, I shoved it on the dummy load and got it nice and warm, you know, the mode where it sounds like a vacuum cleaner.



https://youtu.be/D40i8F6f9ls



On a pure sine wave input the limiter tends to pump as it approaches max output, I doubt this is likely in normal use.


What sort of output voltages were you getting, and what was the load connected?

TIA,

Chris
Quality sound from Sheffield
www.grimshawaudio.com
Back to Top
 Post Reply Post Reply Page  <1 224225226227228 260>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.262 seconds.