Leinster Lad Posted October 12, 2020 Share Posted October 12, 2020 Speaker protection is in 3 Link to comment Share on other sites More sharing options...
MarcAL Posted October 12, 2020 Author Share Posted October 12, 2020 (edited) Those speaker protection units look quite serious. Some real nice and quality parts used. MarcAL. Edited October 12, 2020 by MarcAL Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 12, 2020 Share Posted October 12, 2020 Thanks Marcus, I am trying to do this very well. Those speaker binding posts, soft starts and speaker protect boards are from https://www.audiophonics.fr/en/ Powered by 12 - 0 - 12 ac I'll use the 15 - 0 - 15 windings from the feruson trannies. right channel from right tranny left channel from left tranny. that way, if either channel blows its power fuse (on the soft start) it will disconnect the speaker instantaneously. should save the speaker from any voltage spikes on the amp output as the rails drop. Really neat how the binding posts bolt directly to the boards. A few more parts trickled in today from Element14. 3 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 16, 2020 Share Posted October 16, 2020 Those metal "U" sections that can be seen sitting on the bottom, between the speaker protect boards are from some old draw slides that I replaced. These will be screwed to the chassis rear panel and the frame of the power supply "module". The center one will have the input cable in it ( magnetic shield as they run under the power suupply module. The outer ones do the same for the speaker cables. Should be really neat Soft starts; I had 800mA fast blow fuses in them and when powering up with empty caps, they blew straight away. So even with the soft starts, the initial surge is greater than 800mA. I then fitted 1 amp fasts blow fuses, waited for all caps to discharge and tried again. Good, no blow ! BUT, you can actually see the fuse wire sag a little at the point of switch on ! Might need to go up a little more? 2 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Power supply module assembly ready to fit to the case. Transformers are rubber mounted to reduce vibration. Earth leads soldered to the shields for earthing 4 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Well, close but not close enough rear panel and left side off to get it in. Now for some bolts 2 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 And it’s in 3 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Not sure about the silver screws. Will get some black ones earths will be at a star point 2 Link to comment Share on other sites More sharing options...
MarcAL Posted October 20, 2020 Author Share Posted October 20, 2020 Wow that is really coming along. Excellent!! 2 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Some more pics 3 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 11 minutes ago, MarcAL said: Wow that is really coming along. Excellent!! Thanks mate. Starting to get some weight to it now Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 2 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Underside showing the 3 channels that will shield the inputs and outputs 2 Link to comment Share on other sites More sharing options...
Leinster Lad Posted October 20, 2020 Share Posted October 20, 2020 Top shot 2 Link to comment Share on other sites More sharing options...
TrevorM Posted November 1, 2020 Share Posted November 1, 2020 Good morning everyone. A have an ETI 5000 Pre and Power amp I built in 86. Amazing kit that runs perfectly to this day. My dilema is due to age and pending down sizing the pre, power amp, speaker protection unit, rack case and Wharfdale equalizer will have to go. It's not something I'm inclined just to sell on gumtree and prefer it to go to those who can do these things justice, such as what I've read here. I don't have the sight, or steadiness of hand to do this anymore sadly. Any ideas at all? Kind regards 3 Link to comment Share on other sites More sharing options...
Leinster Lad Posted November 1, 2020 Share Posted November 1, 2020 Hi Trevor, please check your inbox Link to comment Share on other sites More sharing options...
Monkeyboi Posted November 3, 2020 Share Posted November 3, 2020 I would recommend replacing all the tantalum capacitors in the LED level meters of the 5000 series pre-amp. They eventually go short-circuit under operating voltage but some brands test okay with a multimeter out of circuit (low test voltage). Ended up replacing all of the tantalums and all the other electrolytics as so many decades on they slowly lose some of their capacitance. Cheers, Alan R. 1 Link to comment Share on other sites More sharing options...
Monkeyboi Posted November 3, 2020 Share Posted November 3, 2020 On 01/11/2020 at 9:15 AM, TrevorM said: Good morning everyone. A have an ETI 5000 Pre and Power amp I built in 86. Amazing kit that runs perfectly to this day. My dilema is due to age and pending down sizing the pre, power amp, speaker protection unit, rack case and Wharfdale equalizer will have to go. It's not something I'm inclined just to sell on gumtree and prefer it to go to those who can do these things justice, such as what I've read here. I don't have the sight, or steadiness of hand to do this anymore sadly. Any ideas at all? Kind regards Nice. Could do with a dust off. Cheers, Alan R. 1 Link to comment Share on other sites More sharing options...
Leinster Lad Posted November 3, 2020 Share Posted November 3, 2020 Thanks for the tip Alan. I have heard of these new fangled aluminium/polymer solid type of caps. Supposed to have much lower ESR than "normal" tantalums ? Any idea if they are any good ? What is the reason for specifying tants instead of normal electros ? Link to comment Share on other sites More sharing options...
TrevorM Posted November 3, 2020 Share Posted November 3, 2020 Hi Alan. The dust is courtesy of the 'maid', and I'm not inclined to argue with her! A good tip regarding caps, and something that was always going to be part of a service, however health issues have robbed me of the vision and dexterity to carry on with it. Now a planned downsizing means there will most likely be no room for it at all sadly. 1 Link to comment Share on other sites More sharing options...
Leinster Lad Posted November 3, 2020 Share Posted November 3, 2020 Hi Trevor. Did you see my message to you ? Link to comment Share on other sites More sharing options...
TrevorM Posted November 3, 2020 Share Posted November 3, 2020 Trying a reply again David. I hate computers. I'm a pen and paper person 1 Link to comment Share on other sites More sharing options...
Monkeyboi Posted November 4, 2020 Share Posted November 4, 2020 On 03/11/2020 at 9:19 AM, Leinster Lad said: Thanks for the tip Alan. I have heard of these new fangled aluminium/polymer solid type of caps. Supposed to have much lower ESR than "normal" tantalums ? Any idea if they are any good ? What is the reason for specifying tants instead of normal electros ? Haven't had enough exposure to the polymer electros to give much of an opinion at this stage. I guess with all newer technologies only time and experience will tell. Tantalums have as you said lower ESR than regular aluminium electrolytics. Therefore they are favoured in power supply decoupling roles as well as low leakage. So often in application notes for say voltage regulator ICs you might see things like recommended the output be decoupled by a 1uF tantalum or a 10uF electrolytic. For some this is confusing. Why the difference in capacitance by an order of magnitude between tantalum and aluminium electrolytic? It's all to do with the effective ESR of the capacitor among other considerations, but in a nutshell the 1uF tantalum is as effective as a 10uF regular electrolytic in this application. The only problem with tantalums IME is they are rarely available in working voltage ratings above 35v and very intolerant of over-voltage even by a small margin. Sometimes when they go faulty they test okay with a lower voltage device like your typical DMM and LCR meters, but back in the circuit they react as faulty. Whilst they do a great job as power supply decoupling capacitors they are IMHO and IME absolutely awful in audio coupling and bypass roles. Capacitors ain't just capacitors Sol. Cheers, Alan R. 1 Link to comment Share on other sites More sharing options...
Leinster Lad Posted November 5, 2020 Share Posted November 5, 2020 18 hours ago, Monkeyboi said: Capacitors ain't just capacitors Sol. Thanks for the explanation Alan. So, I was looking at Tantalum caps @ element14 to build the BOM for the 5000 pre..... Is there any way that you could explain to me the incredible range and price difference between caps of identical specs (uf, V ) ?? I get different manufactures and to some extent different tolerances but ......... How the heck is anyone able to chose one over the other ??? Link to comment Share on other sites More sharing options...
Leinster Lad Posted November 5, 2020 Share Posted November 5, 2020 And what has the voltage rating got to do with it. EG, C1 , the input cap on the VU meter board is specified as 1 uF @ 6v ..... can't find one. But I can find a 1uF in 10v and a 16v and a 25v .... Others are spec'd at either 16v or 25v . Is there any actual technical reason ? Why not just spec all of them at 25v ? gives a good margin over the supply rail voltages and would simplify the BOM, surely ? Link to comment Share on other sites More sharing options...
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