tag:blogger.com,1999:blog-8044784353067686026.post5197180940310797653..comments2024-02-25T10:43:28.969+00:00Comments on m0xpd's <i>'Shack Nasties'</i>: Analysis of the Tube Screamerm0xpdhttp://www.blogger.com/profile/13241728975907453128noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-8044784353067686026.post-16773362886354218212016-11-25T13:32:36.041+00:002016-11-25T13:32:36.041+00:00I already got my answers! Your article was very he...I already got my answers! Your article was very helpful! Thank you for that.<br /><br />I also found very interesting information on the diodes in this page: http://www.bteaudio.com/articles/TSS/TSS.html<br /><br />Having read that same page i now understand the question related to the mix of the original input signal with the clipped one that you talked about in this article:<br /><br />"Various commentators have spoken of the action of the Tube Screamer being largely derived from the fact that the clip stage passes a mixture of the un-processed guitar sound plus the distorted sound - this is seen in the sum in the square bracket of the equation above. I confess that I'm not sure how useful this distinction actually is to understanding the system - particularly as Zf/Zin > > 1."<br /><br />As the diodes turn on Zf/Zin will not have the full impact since the output of the the op amp will be limited by the diodes. Therefore it really makes a big diference that the input unclipped signal is mixed with the ouuput of that stage.<br /><br />Again, thank you for this article! I now developed my simulation.gackrull28https://www.blogger.com/profile/12690236523500853153noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-10935111897532838902016-11-24T19:38:01.680+00:002016-11-24T19:38:01.680+00:00Notice (in line two of the post) that this was adv...Notice (in line two of the post) that this was advertised as a SMALL-SIGNAL analysis.<br /><br />The whole concept of 'Frequency Response', in the sense used here (Laplace / Fourier analysis, etc) breaks down as soon as the signals are large enough to cause the diodes to switch. Then you're forced to measure (as reported in the last part of the post) or simulate (as you are doing - in LTSpice or similar) or use higher-order methods of 'analysis', well outside the scope of this blog.m0xpdhttps://www.blogger.com/profile/13241728975907453128noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-61564253086129409202016-11-24T15:34:57.873+00:002016-11-24T15:34:57.873+00:00Hi!
I have been analyzing this circuit and i foun...Hi!<br /><br />I have been analyzing this circuit and i found the diodes (of the clip stage) role hard to interpret!<br />I simulated the circuit using ltspice and they have a big impact since it is hard to keep the voltage obtained by the product of the input and the op amp gain under the forward voltage.<br />They will have impact on the frequency response when such voltages are reached!<br /><br />I would love some help on this!<br /><br />Thank you.gackrull28https://www.blogger.com/profile/12690236523500853153noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-45591464056804157182016-11-24T15:30:07.287+00:002016-11-24T15:30:07.287+00:00Hi!
I have been analyzing this circuit and i foun...Hi!<br /><br />I have been analyzing this circuit and i found no information about the clipping diodes! I noticed you discarded them of your analysis since the forward voltage is not reached. But what if it was? What impact would it have? I simulated the frequency response in LTSpice and the diodes have a big impact since it is hard that not to reach their forward voltage...<br /><br />Glad for some help!gackrull28https://www.blogger.com/profile/12690236523500853153noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-65909565263865661792015-01-15T11:44:09.115+00:002015-01-15T11:44:09.115+00:00Sorry Lukas - I will not be publishing the MATLAB ...Sorry Lukas - I will not be publishing the MATLAB code.m0xpdhttps://www.blogger.com/profile/13241728975907453128noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-12850566757735306672015-01-13T15:41:37.824+00:002015-01-13T15:41:37.824+00:00Hey m0xpd,
I'm working on a little project at ...Hey m0xpd,<br />I'm working on a little project at my university, where I have to emulate the TS808 with MATLAB and I really need a little help there...<br />Would it be possible, that you could send me your MATLAB-codes? I especially need the transfer function in the correct form (so that MATLAB can work with it)<br />I hope you can help me!<br />Best regards!!Anonymoushttps://www.blogger.com/profile/18298571170362622227noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-78193957892886708042014-11-05T08:49:37.358+00:002014-11-05T08:49:37.358+00:00Simulation was done in LTSpice, Measurement was do...Simulation was done in LTSpice, Measurement was done using an Audio Frequency Analyser made by 01dB and Analysis was done on "pencil and paper", resulting in Laplace-domain expressions which were evaluated in MATLAB. The Graphs were produced in MATLAB. m0xpdhttps://www.blogger.com/profile/13241728975907453128noreply@blogger.comtag:blogger.com,1999:blog-8044784353067686026.post-36996155571638615892014-11-04T08:37:02.059+00:002014-11-04T08:37:02.059+00:00which program you use to simulating, analysing and...which program you use to simulating, analysing and measuring this circuit Anonymoushttps://www.blogger.com/profile/01912920415105711645noreply@blogger.com