UFN Posted March 15, 2015 Report Posted March 15, 2015 That worked, thanks for the tip In other news, I fixed the offset-issue. Didn't have to do anything except realize that the servo op-amp is a dual-OP and not the usual OP27 Note to self, read the schematic properly FFS! //UFN
ang728 Posted June 18, 2015 Report Posted June 18, 2015 (edited) what value of input pot should be used on squarewave klone? read 10K somewhere before but I can't find it or maybe should use higer value like 50K/100K since it's fet input? thanks Edited June 18, 2015 by ang728
kevin gilmore Posted June 18, 2015 Report Posted June 18, 2015 well I do 10k, just because I don't want too many different versions in stock. but 50k or 100k works fine for this
ang728 Posted June 21, 2015 Report Posted June 21, 2015 Thanks ! well I do 10k, just because I don't want too many different versions in stock. but 50k or 100k works fine for this
ang728 Posted October 9, 2015 Report Posted October 9, 2015 finally finished the build with some sp style wiring
spritzer Posted October 9, 2015 Author Report Posted October 9, 2015 I like that one a lot!! I have a pile of these that I need to finish at some point as it is a really good amp. Any troubles with that feedback switch?
ang728 Posted October 9, 2015 Report Posted October 9, 2015 (edited) I like that one a lot!! I have a pile of these that I need to finish at some point as it is a really good amp. Any troubles with that feedback switch? Thanks! besides not as "hi gain" as I thought , actually they work well .Love that sound with switch on btw,I am curious about how does this feedback design work in the circuit , any paper or keywords that I can learn from ? Edited October 9, 2015 by ang728
MLA Posted April 5, 2016 Report Posted April 5, 2016 What would the current draw be for a balanced version? Inside or outside GRLV range ( think I saw 1,5 amps somewhere)?
ang728 Posted April 5, 2016 Report Posted April 5, 2016 (edited) 26 minutes ago, MLA said: What would the current draw be for a balanced version? Inside or outside GRLV range ( think I saw 1,5 amps somewhere)? I put them on lab bench psu before,can't remember what's exact number of current draw,but I'm sure under 1.5A then built a slimmer case version a while ago using orginal GR and works pretty well Edited April 5, 2016 by ang728
MLA Posted September 2, 2016 Report Posted September 2, 2016 On 2 december 2014 at 10:03 PM, kevin gilmore said: about 120ma, measure across the 10 ohm resistors Just double checking: 120ma, not mv? Can't get near the ma version, so thought I'd ask before pulling things apart...
kevin gilmore Posted September 2, 2016 Report Posted September 2, 2016 120ma thru 10 ohms is... 1.2 volts at least that is what I remember 1
ang728 Posted September 2, 2016 Report Posted September 2, 2016 39 minutes ago, MLA said: Just double checking: 120ma, not mv? Can't get near the ma version, so thought I'd ask before pulling things apart... YES,it's 120mA,you should have 1.2V reading across 10R but 100mA-110mA sounds best IMO
MLA Posted September 2, 2016 Report Posted September 2, 2016 Great, thanks! Can't get more than halfway there, so I've screwed up somewhere... Makes for a nice evening of troubleshooting
MLA Posted September 2, 2016 Report Posted September 2, 2016 (edited) Ok, not so long evening, a bad solder joint it was. Nice and steady at 120 ma now. Guess I have to go watch a movie instead. Boring Many thanks for both of your very quick responses!!! Edited September 2, 2016 by MLA
jose Posted October 7, 2018 Report Posted October 7, 2018 (edited) Sorry for refloating this thread. I'm listening to my "SquareWave KG latest version" in SE configuration. (Thanks Dr. Gilmore) It works great and is very simple to assemble. I have regulated the BIAS @ 120mA without problems and could even raise it much more. I have used a 100K resistor to make the servo act as fast as possible and from the beginning the offset is 0 Vdc so I don't need wait for listening music. I matched all the transistors as best as possible but with the MJE200 and MJE201 it was impossible to find an identical pair. ? The next step is to install it in a box but I'm hesitating, Is it worth making a balanced version? Is there much difference between the SE vs. Balanced version? I have enough material and pcb´s to do this without problems but if this does not make sense, I'll leave it in SE configuration. Edited October 7, 2018 by jose
kevin gilmore Posted October 7, 2018 Report Posted October 7, 2018 probably not worth making a balanced version, the output impedance is not super low.
jose Posted November 9, 2018 Report Posted November 9, 2018 Yesterday I was listening to the Square Wave with different headphones (hd800, W5000 ....) and I was wondering if the output impedance changes when changing the gain (Low to High)? I understand that if he does it, I do not know exactly how much or if the change is very radical.
mdr30 Posted March 1, 2019 Report Posted March 1, 2019 Just warmed this up, sounds terrific. Think I'll populate the other two boards for a balanced Squarewave.
Rossliew Posted March 3, 2019 Report Posted March 3, 2019 Sorry how does this amp sound compared to the dynalo?
grawk Posted March 3, 2019 Report Posted March 3, 2019 19 minutes ago, Rossliew said: Sorry how does this amp sound compared to the dynalo? mostly the same
jose Posted March 3, 2019 Report Posted March 3, 2019 The Squarewave does not sound bad but IMHO dynalo is superior: More balanced, more musical ...
Rossliew Posted March 4, 2019 Report Posted March 4, 2019 Thanks. Thought the Squarewave would be a nice complement to the Dynalo.
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