John Warren Posted December 3, 2016 Share Posted December 3, 2016 Anyone have a PDF of the schematic (or PDF of the service manual)? If so, could you PM to me? Thanks in advance! Quote Link to comment Share on other sites More sharing options...
JL Sargent Posted December 3, 2016 Share Posted December 3, 2016 Will the D75 service manual help? http://rdn.harmanpro.com/product_documents/documents/3603_1438110698/Copy_of_D75_Service_Manual__original.PDF Quote Link to comment Share on other sites More sharing options...
John Warren Posted December 3, 2016 Author Share Posted December 3, 2016 I don't have the actual amp in my possession yet but I've been looking at the D-75 for insight. Crown has a list of SMs on their website but the D-45 isn't there. I did sent a request so we shall see. Thanks for responding. Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 3, 2016 Share Posted December 3, 2016 Mine says D45-75A I can send it to you. Don't know if its any different. Quote Link to comment Share on other sites More sharing options...
John Warren Posted December 3, 2016 Author Share Posted December 3, 2016 Excellent! Thank you. Quote Link to comment Share on other sites More sharing options...
John Warren Posted December 8, 2016 Author Share Posted December 8, 2016 I picked up a D-45 and now have it in my possession. http://www.northreadingeng.com/Forums/viewtopic.php?f=8&p=51&sid=cc3ca2d61cc46c58d003f86158eea832#p51 So, let's take it apart! Quote Link to comment Share on other sites More sharing options...
mike stehr Posted December 9, 2016 Share Posted December 9, 2016 Cool reading! There is a D75 around locally for rather cheap...still pondering... Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 10, 2016 Share Posted December 10, 2016 Are you going to do some hot rodding? I have some 33uf black gates if interested. Quote Link to comment Share on other sites More sharing options...
John Warren Posted December 10, 2016 Author Share Posted December 10, 2016 1 hour ago, The Dude said: Are you going to do some hot rodding? I have some 33uf black gates if interested. I'm first trying the mods Mark Deneen proposed a while ago on the so-called "Duke". I have a couple other ideas I'll investigate too. 1 Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 10, 2016 Share Posted December 10, 2016 I'm first trying the mods Mark Deneen proposed a while ago on the so-called "Duke". I have a couple other ideas I'll investigate too. Thats why bought mine along with the black gates Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 10, 2016 Share Posted December 10, 2016 I am interested in seeing what comes of all of this. Quote Link to comment Share on other sites More sharing options...
JL Sargent Posted December 10, 2016 Share Posted December 10, 2016 What were Marks mods? I remember the thread but I guess it's gone now? I have a D-45 myself. They are available for reasonable on Ebay all the time. Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 10, 2016 Share Posted December 10, 2016 What were Marks mods? I remember the thread but I guess it's gone now? I have a D-45 myself. They are available for reasonable on Ebay all the time. If you haven't all ready, do a search of my threads. I started one a couple years back in regards to this amp and mods. Maybe it was lost or deleted. I am on Tapatalk now and cant seem to find the search function Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted December 10, 2016 Share Posted December 10, 2016 I have the whole thread in a pdf on my phone if I could justfigure out how to attach it. Just sold the Duke last week. Miss it already Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted December 10, 2016 Share Posted December 10, 2016 Try this D-45_Update_The_Duke_Klipsch-1.pdf Quote Link to comment Share on other sites More sharing options...
JL Sargent Posted December 11, 2016 Share Posted December 11, 2016 Thanks Carl, Mark did make some interesting changes to the amp including faster op amps. One thing I didn't find is what op amps he installed? Quote Link to comment Share on other sites More sharing options...
The Dude Posted December 11, 2016 Share Posted December 11, 2016 1 hour ago, JL Sargent said: Thanks Carl, Mark did make some interesting changes to the amp including faster op amps. One thing I didn't find is what op amps he installed? It might be mentioned here From what I was told in the original thread, there might better OP amps now. So I started to do some research, but that was all the further I got. I am glad to see this concept get some more attention. Quote Link to comment Share on other sites More sharing options...
mike stehr Posted December 11, 2016 Share Posted December 11, 2016 "I used the TLS084, mostly because of pinout restrictions and not wanting to out run the rest of the circuit." It's all I can gather from the thread, other than a Texas Instruments device with 2X the speed. Still pondering on the D75 locally...if it's still around in a week when I know my cash situation better I'll hit them up with a offer. It's an older unit, with the aluminum knobs and gray faceplate...along with speaker binding posts, and balanced inputs, with 1/4" jack inputs as well. It's a bad time of year for me to buy stuff... Quote Link to comment Share on other sites More sharing options...
JL Sargent Posted December 12, 2016 Share Posted December 12, 2016 The TL084 is a crazy cheap IC. I suspect these caps would work for the power supply upgrade? http://www.ebay.com/itm/2x-10000uF-50V-NOVER-Audio-Grade-Power-85-C-capacitor/321449052896?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D2220071%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38530%26meid%3D48892c5c87d34511b626a75c250e9099%26pid%3D100005%26rk%3D6%26rkt%3D6%26sd%3D272376598847 Or these? http://www.ebay.com/itm/4-PCS-10-000-10000UF-50V-Electrolytic-Capacitor-105-degrees-USA-FREE-SHIPPING-/272376598847?hash=item3f6ae9113f:g:LJ4AAOSwKPNTyXDv Then there are the smaller Black Gates Mark installed? 50v 2.2uf or so? Quote Link to comment Share on other sites More sharing options...
John Warren Posted December 13, 2016 Author Share Posted December 13, 2016 Except for the chassis, the power transformer, the PC boards and the front panel knobs, I can source everything needed to completely rebuild/mod this amplifier from Mouser and it's lower cost. There are two 14 pin chips, one is the input stage (quad differential amplifier) and the other is a voltage comparator (to drive the overload LED indicators). Everything else is a discrete. The power supply caps are screw terminal, high posts, 1/2" spacings. The Mouser PN for a 12,000uF cap with the right configuration to shoe-horn into the D45 is http://www.mouser.com/search/ProductDetail.aspx?r=598-DCMC50V123 Does increasing the filter capacitor size improve things? Well, I do measure a large drop in ripple when I straddle 9000uF to each side of the supply (scroll down): http://www.northreadingeng.com/Forums/viewtopic.php?f=8&t=9 Will this translate into reduced distortion is still to be determined (my parts are on order). 1 Quote Link to comment Share on other sites More sharing options...
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