Ostripper found that a combination of 220r emitter resistor and 220r collector resistor met his criteria for a "protected" VAS buffer.
You can try this if you have the same or similar criteria as Ost.
I prefer to use a higher value collector resistor and it's size is determined by the amount of power that the Buffer can dissipate during fault condition.
You can try this if you have the same or similar criteria as Ost.
I prefer to use a higher value collector resistor and it's size is determined by the amount of power that the Buffer can dissipate during fault condition.
Both resistors reduces current from colector to emitter
When you install higher resistance in the emitter you are also controlling base to emitter current...... all these things increases stage protection.
Enjoy your amplifier folks, as having your modifications you will now believe it will be much better and reliable....and this kind of peace in your mind is always very positive.
I tried here at my home and i found that 1K at the emitter results in worse sonics than 220 ohms...about colector i cannot say as i have not tried...but if you are satisfied with the results..well...this is what i want...to see you satisfied and happy.
regards,
Carlos
When you install higher resistance in the emitter you are also controlling base to emitter current...... all these things increases stage protection.
Enjoy your amplifier folks, as having your modifications you will now believe it will be much better and reliable....and this kind of peace in your mind is always very positive.
I tried here at my home and i found that 1K at the emitter results in worse sonics than 220 ohms...about colector i cannot say as i have not tried...but if you are satisfied with the results..well...this is what i want...to see you satisfied and happy.
regards,
Carlos
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The 220R emitter resistor is quite dependant on the B-E characteristics of the main VAS device. What would sound "better" or be more linear (THD) would depend on the device (MJE350 , 2sc3503, BC-xxx). The collector side resistor will just crudely limit current through the follower. A full active current limiter (Bob Cordell's Lin amp example - below 1) , is the only "100%" method.
PS - even if your output stage goes "up in smoke" , your VAS will survive !!
OS
PS - even if your output stage goes "up in smoke" , your VAS will survive !!
OS
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This was used a long time ago.... something not so different Ostripper
Was in the Precision 1 amplifier... several guys had boards from Nordic group buy, i do not know if this belongs to your time in the forum...i hope so...you started 2008 i think.
The problem is that this disturbs the sound...sound becomes awfull..something so bad alike V/I limiter, and this works more or less in the same style...i have used to be in the safe side, but i told builders to listen without the circuit, disconnecting the circuit and to test... some of them returned to me that would use the amplifier without this protection....i have used myself without this protection.
V/I limiters and this style of circuit is something i will never use (I did it once and i regret), unless i decide to make an amplifier to be huge to professional use, and low cost, as these protections allow us to use cheaper parts and less output pairs.... reducing production cost, increasing profit and using the belief that with all that power no one will be able to listen quality..so... sonics goes secondary in some cases in the name of profit...... i do not have profit...so...my case is sonics..only sonics.
I believe you have tested...the real trouble we have Ostripper, is that we have a lot of guys that defends these things and have never installed, switched it on and off...in other words...the "think"...or "believe"..but they do not really know what they are talking about...say...they understand the technicall side but have not perceive, or listened, a real good sound... and real good sound does not use any protection...as protections use to harm sonics..you see LM chip...this 36XX or 38XX series.... sound is good till 20 watts rms..them protection engage and all stuff turns awfull.
Well... this is all point of views..... mine is based in testings...i do think yours are made based in testings too..surprises me you defending this.
Please, take a look in the schematic...this was done... a long time ago..was listened, tested, discussed, tweaked, compared and people have made reviews about.... the old story once again...hehehehehe...as Hugh Dean told me once..this forum is ciclic.... now we are in this season once again... the season "do what books show"
We are living another cicle of illusion, there are several folks saying sonics depends on part's selection.... i have tested in my amplifiers and the sound is absolutelly the same with boutique parts and junk parts... differences are very small to say we can have advantage with one or other... these things are more religion than science...people believe.... even beeing non sense alike speaker audio cables and RCA special cables...only the ones have spent their precious money in these things defends ..... if they do different, they will have to accept they was fooled...so..it is better to believe it worth the money applied..... psychology explains these things...we believe following our own needs.
Example:
- "My wife is the best"....when people do not know others.
- "My son is the most clever young boy".... so, there are only most clever young boys..all daddies thinks the same.
- "My amplifier is the best one" (when the guy have never listened other..hehehehehhe)
Dx amplifiers will remain the same... the Dx amplifier, the HRII, the DHR Turbo, the Troyan, the Precision 1, the Trust and Dx Blame ES, Dx Blame ST, Dx Blame MKII and Dx Blame MKII Superchargeed...you will return to this forum in 5 years and you will see the same amplifier.. they were tested and approved and will not be modified.... sadly, the Precison 1 will have this protection that i regret so much to accept to include it in the Precision 1.
I will not continue with this conversation..because i feel deeply ashamed as i have used...i could say that i was drunk when i did...but as i have never drink more than a wine during christmas i cannot say i was drunk....i was never drunk to use this as excuse to by awfull decision about.
I did talked a little Ostripper as you are very important to the forum, you produce things and you publish what you make..so... a real DIY... and WE are rarity.
By the way...your circuit constituted by C6, C7 and R19 was tested using several different values....awfull sound i had...no way to try that once again.
We are constantly and daily evoluting Ostry..this depends on time and search and research... a lot of sweat on that.... some try and error, some frustration and some success...you realised you had bad speakers... and this turns your previous research not so precise...so..you see how much we learn...also, your next speakers may let you perceive other things about sonics too.
regards,
Carlos
Was in the Precision 1 amplifier... several guys had boards from Nordic group buy, i do not know if this belongs to your time in the forum...i hope so...you started 2008 i think.
The problem is that this disturbs the sound...sound becomes awfull..something so bad alike V/I limiter, and this works more or less in the same style...i have used to be in the safe side, but i told builders to listen without the circuit, disconnecting the circuit and to test... some of them returned to me that would use the amplifier without this protection....i have used myself without this protection.
V/I limiters and this style of circuit is something i will never use (I did it once and i regret), unless i decide to make an amplifier to be huge to professional use, and low cost, as these protections allow us to use cheaper parts and less output pairs.... reducing production cost, increasing profit and using the belief that with all that power no one will be able to listen quality..so... sonics goes secondary in some cases in the name of profit...... i do not have profit...so...my case is sonics..only sonics.
I believe you have tested...the real trouble we have Ostripper, is that we have a lot of guys that defends these things and have never installed, switched it on and off...in other words...the "think"...or "believe"..but they do not really know what they are talking about...say...they understand the technicall side but have not perceive, or listened, a real good sound... and real good sound does not use any protection...as protections use to harm sonics..you see LM chip...this 36XX or 38XX series.... sound is good till 20 watts rms..them protection engage and all stuff turns awfull.
Well... this is all point of views..... mine is based in testings...i do think yours are made based in testings too..surprises me you defending this.
Please, take a look in the schematic...this was done... a long time ago..was listened, tested, discussed, tweaked, compared and people have made reviews about.... the old story once again...hehehehehe...as Hugh Dean told me once..this forum is ciclic.... now we are in this season once again... the season "do what books show"
We are living another cicle of illusion, there are several folks saying sonics depends on part's selection.... i have tested in my amplifiers and the sound is absolutelly the same with boutique parts and junk parts... differences are very small to say we can have advantage with one or other... these things are more religion than science...people believe.... even beeing non sense alike speaker audio cables and RCA special cables...only the ones have spent their precious money in these things defends ..... if they do different, they will have to accept they was fooled...so..it is better to believe it worth the money applied..... psychology explains these things...we believe following our own needs.
Example:
- "My wife is the best"....when people do not know others.
- "My son is the most clever young boy".... so, there are only most clever young boys..all daddies thinks the same.
- "My amplifier is the best one" (when the guy have never listened other..hehehehehhe)
Dx amplifiers will remain the same... the Dx amplifier, the HRII, the DHR Turbo, the Troyan, the Precision 1, the Trust and Dx Blame ES, Dx Blame ST, Dx Blame MKII and Dx Blame MKII Superchargeed...you will return to this forum in 5 years and you will see the same amplifier.. they were tested and approved and will not be modified.... sadly, the Precison 1 will have this protection that i regret so much to accept to include it in the Precision 1.
I will not continue with this conversation..because i feel deeply ashamed as i have used...i could say that i was drunk when i did...but as i have never drink more than a wine during christmas i cannot say i was drunk....i was never drunk to use this as excuse to by awfull decision about.
I did talked a little Ostripper as you are very important to the forum, you produce things and you publish what you make..so... a real DIY... and WE are rarity.
By the way...your circuit constituted by C6, C7 and R19 was tested using several different values....awfull sound i had...no way to try that once again.
We are constantly and daily evoluting Ostry..this depends on time and search and research... a lot of sweat on that.... some try and error, some frustration and some success...you realised you had bad speakers... and this turns your previous research not so precise...so..you see how much we learn...also, your next speakers may let you perceive other things about sonics too.
regards,
Carlos
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You have the "trigger point" too low.Your R19, (DX precision -22R) is the same as Cordell's , setting the limiter to 26ma. CCS is set at 11-12ma on the "precision". Would be better to split R19 into 10R/10R ,the limiter threshold (52ma) would be much further away from normal operating currents. My CCS is at 6mA / threshold is at 26mA , limiter has nearly infinite impedance with even high power/voltage use. 4:1 limiter/normal ratio is best (26/6 or 52/11).
The TMC works the best on a CCS based amp(VAS) , NOT on a bootstrapped one. I came to the same conclusion as you , (bad sound) on my "strapped" amp (BX). The CCS based one (AX) , was greatly improved.
OS
OS
Hello Mr. DX Sir,
Here are the pictures of my second DX Blame MKII supercharged board. Both boards are now working!
Analog Multimeter was set to 0.1 vdc as the DC offset was actually less than or close to 1mV. This was the lowest DC offset I’ve ever seen on an amplifier. Rail voltage is at -/+ 33Vdc @ 6 amperes. I will be using -/+ 45Vdc @ 10 amps with 40,000 uf capacitor bank on each rail.
By the way, do you have any updates for the DHR Turbo? I want to build this one as well. I hope Sir Alex MM would be able to make a final PCB layout like the very first layout he did that has dual in line transistors with the VAS located on the other end of the board. The final one with the VAS on the center was ok but I like the boards having the VAS on the other ends and the output is on one side. This way I can mount them on one single heatsink. In our locality we only have one type of heatsink like the ones shown on the attached photos.
Thank you all for making this amp available to all DIYers!
Regards,
Blueice23
Here are the pictures of my second DX Blame MKII supercharged board. Both boards are now working!
Analog Multimeter was set to 0.1 vdc as the DC offset was actually less than or close to 1mV. This was the lowest DC offset I’ve ever seen on an amplifier. Rail voltage is at -/+ 33Vdc @ 6 amperes. I will be using -/+ 45Vdc @ 10 amps with 40,000 uf capacitor bank on each rail.
By the way, do you have any updates for the DHR Turbo? I want to build this one as well. I hope Sir Alex MM would be able to make a final PCB layout like the very first layout he did that has dual in line transistors with the VAS located on the other end of the board. The final one with the VAS on the center was ok but I like the boards having the VAS on the other ends and the output is on one side. This way I can mount them on one single heatsink. In our locality we only have one type of heatsink like the ones shown on the attached photos.
Thank you all for making this amp available to all DIYers!
Regards,
Blueice23
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Thank you by the kind support, the enthusiasm and the review
DHR Turbo is excelent for bass.... very good unit.... sounds warm and strong..sound comes from the Devil's throat from the deeps of hell... the earthquake sound, the thunder...all this things sounds very real and present.
Midranges and treble are fine too..but the best point is the bass...longer than usual, deeper than usual, not so perfect or so precise..but the bass is better than the Dx Blame ES, ST, MKII and Supercharged.
About Alex to modify boards...well...this is up to him...write to him and ask that...if he decide to change things i will accept as he is Dx Corporation's designer too....i will appreciate to take a look in advance, but really this is strongly needed as Alex does not use to make mistakes...he is very good in his job.
I am sure you will enjoy...go deep into it and be sure you have made a good decision about..... all my amplifiers where tested... they are not simulator amplifiers.... all them assembled and tested for monthes, under torture and built by several forum folks and no one of them have complained.
There's no updates to the DHR turbo.
Thank you by the pictures too.
regards,
Carlos
DHR Turbo is excelent for bass.... very good unit.... sounds warm and strong..sound comes from the Devil's throat from the deeps of hell... the earthquake sound, the thunder...all this things sounds very real and present.
Midranges and treble are fine too..but the best point is the bass...longer than usual, deeper than usual, not so perfect or so precise..but the bass is better than the Dx Blame ES, ST, MKII and Supercharged.
About Alex to modify boards...well...this is up to him...write to him and ask that...if he decide to change things i will accept as he is Dx Corporation's designer too....i will appreciate to take a look in advance, but really this is strongly needed as Alex does not use to make mistakes...he is very good in his job.
I am sure you will enjoy...go deep into it and be sure you have made a good decision about..... all my amplifiers where tested... they are not simulator amplifiers.... all them assembled and tested for monthes, under torture and built by several forum folks and no one of them have complained.
There's no updates to the DHR turbo.
Thank you by the pictures too.
regards,
Carlos
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Hello Mr DX Sir,
Thank you so much for the Information. My main purpose of building the DHR turbo is for bass units. I have built 2 3way crossover circuits and I will incorporate this with the DHR turbo. The mids and highs will be driven by the DX blame amps. I will be making four DX blame amps and two DHR turbo.
I have sent a request already to Mr. Alex MM. I am now waiting patiently for his positive response.
Regards,
Blueice23
Thank you so much for the Information. My main purpose of building the DHR turbo is for bass units. I have built 2 3way crossover circuits and I will incorporate this with the DHR turbo. The mids and highs will be driven by the DX blame amps. I will be making four DX blame amps and two DHR turbo.
I have sent a request already to Mr. Alex MM. I am now waiting patiently for his positive response.
Regards,
Blueice23
Live show from Brazil....forum friends invited to see now!
type:
YouTube - carnaval's Channel
regards,
Carlos
type:
YouTube - carnaval's Channel
regards,
Carlos
I suggest you folks, to build the Dx Blame ST amplifier
or any Dx Blame amplifier..... or any Blameless style amplifier...all them are fine as i could build some to listen.
You can etch by yourself your boards...all plans are here:
Greg's Web Site
And also here:
*
You have several threads that supports you... Dx Blame ES thread, Dx Blame ST thread, Dx Supercharged thread and you can come to me to talk about and to have some help at my personnal adress or in this same forum, this same thread:
nanabrother@hotmail.com
Here you have Mitchel's group buy... for a while closed:
http://www.diyaudio.com/forums/grou...i-mkii-supercharged-groub-buy-interest-5.html
Here the group by Rudi is the manager:
http://www.diyaudio.com/forums/group-buys/172901-dx-blame-group-buy.html
It is all DIY amplifiers.... Mitchel group by is closed (at least for a while)...Rudi group buy may produce second or third round soon and he has a lovely paper explaining details how to build....Rudi loves to help too...you can search Rudi and ask him whatever you want/need too.
It is for free.... no profit.... an amplifier for our community, as it started from Doctor Self Design, the published Blameless, and he is inside our community being one of the most highly skiled experts/engineers we may have.
The seed was planted to the forum produce boards...this is a plan, an idea..and the seed is in good land to grow up.... some time will be needed to se the plant grow...we gonna be waiting asking God to help us to allow forum to have good amplifiers (not only mine ones) offered to you by cheap price..having the designer/creator/modifier/copier or anything you may call or understand...present in our forum having the desire to help and to see people building, posting pictures and feeling happy.
Here you have a green board from the closed Brazilian group buy...around 100 boards alike that where offered and 35 percent already build their amplifiers or have started...the blue board, the supply board if from the Supercharged..it has not rectifiers in the board...a tiny board.
regards,
Carlos
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or any Dx Blame amplifier..... or any Blameless style amplifier...all them are fine as i could build some to listen.
You can etch by yourself your boards...all plans are here:
Greg's Web Site
And also here:
*
You have several threads that supports you... Dx Blame ES thread, Dx Blame ST thread, Dx Supercharged thread and you can come to me to talk about and to have some help at my personnal adress or in this same forum, this same thread:
nanabrother@hotmail.com
Here you have Mitchel's group buy... for a while closed:
http://www.diyaudio.com/forums/grou...i-mkii-supercharged-groub-buy-interest-5.html
Here the group by Rudi is the manager:
http://www.diyaudio.com/forums/group-buys/172901-dx-blame-group-buy.html
It is all DIY amplifiers.... Mitchel group by is closed (at least for a while)...Rudi group buy may produce second or third round soon and he has a lovely paper explaining details how to build....Rudi loves to help too...you can search Rudi and ask him whatever you want/need too.
It is for free.... no profit.... an amplifier for our community, as it started from Doctor Self Design, the published Blameless, and he is inside our community being one of the most highly skiled experts/engineers we may have.
The seed was planted to the forum produce boards...this is a plan, an idea..and the seed is in good land to grow up.... some time will be needed to se the plant grow...we gonna be waiting asking God to help us to allow forum to have good amplifiers (not only mine ones) offered to you by cheap price..having the designer/creator/modifier/copier or anything you may call or understand...present in our forum having the desire to help and to see people building, posting pictures and feeling happy.
Here you have a green board from the closed Brazilian group buy...around 100 boards alike that where offered and 35 percent already build their amplifiers or have started...the blue board, the supply board if from the Supercharged..it has not rectifiers in the board...a tiny board.
regards,
Carlos
An externally hosted image should be here but it was not working when we last tested it.
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Please builders... in especial the ones have etched their own boards
Post pictures please.
A good sound quality for you to test your equipment...use equalizer with loudness contour..increase low till 125 hertz (10db to 3 db) ..increase 4K, 8K ands 16K....a touch in 1K and 2K too:
YouTube - YouTube/Carnaval - Ivete Sangalo Ao vivo - Balakbak
http://www.youtube.com/watch?v=JOPaCeCyhq4&feature=feedlik
regards,
Carlos
Post pictures please.
A good sound quality for you to test your equipment...use equalizer with loudness contour..increase low till 125 hertz (10db to 3 db) ..increase 4K, 8K ands 16K....a touch in 1K and 2K too:
YouTube - YouTube/Carnaval - Ivete Sangalo Ao vivo - Balakbak
http://www.youtube.com/watch?v=JOPaCeCyhq4&feature=feedlik
regards,
Carlos
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Listen the Dx Blame recorded using microphone Panasonic
An electret condenser one:
YouTube - Dx Blame, excellence in audio amplifiers
regards,
Carlos
An electret condenser one:
YouTube - Dx Blame, excellence in audio amplifiers
regards,
Carlos
Here the Dx Blame best performance in youtube recordings
This was recorded by a friend using a Nokia cell phone... speakers are special, so listen the audio quality.
YouTube - MY DIY STEREO, DX BLAME ST, AIKIDO
Crank your volume all the way up and reinforce deep bass and some high end treble to compensate encoding and decoding losses.
regards,
Carlos
This was recorded by a friend using a Nokia cell phone... speakers are special, so listen the audio quality.
YouTube - MY DIY STEREO, DX BLAME ST, AIKIDO
Crank your volume all the way up and reinforce deep bass and some high end treble to compensate encoding and decoding losses.
regards,
Carlos
Nice videos, Carlos.
I finally have some spare time so I plan on finishing my DX Blame based on Rudi's beautiful red and gold PCBs. The only bits I need are components for the soft-start circuit and a suitable chassis. I'll probably use the soft-start offered with the Brazilian kit, but may use ballast resistors instead of a thermistor.
Regards,
Nikolay
I finally have some spare time so I plan on finishing my DX Blame based on Rudi's beautiful red and gold PCBs. The only bits I need are components for the soft-start circuit and a suitable chassis. I'll probably use the soft-start offered with the Brazilian kit, but may use ballast resistors instead of a thermistor.
Regards,
Nikolay
I have installed a Dx Blame ST to work as a subwoofer amplifier
Supply is 17 plus 17 volts supplies:
See these videos that will clarify the whole thing:
YouTube - Dx Blame ST as subwoofer amp. -17+17V supplies - chapter 1
YouTube - Dx Blame ST as subwoofer amp. -17+17V supplies - chapter 2
regards,
Carlos
Supply is 17 plus 17 volts supplies:
See these videos that will clarify the whole thing:
YouTube - Dx Blame ST as subwoofer amp. -17+17V supplies - chapter 1
YouTube - Dx Blame ST as subwoofer amp. -17+17V supplies - chapter 2
regards,
Carlos
My Blame ST
A few of photos of my completed BlameST. Based on Rudi's boards (which are a dream to work with.)
I am still trying with different pre-amp and speaker combinations but I really enjoy what I hear.
Thank you Carlos.
Ryan
A few of photos of my completed BlameST. Based on Rudi's boards (which are a dream to work with.)
I am still trying with different pre-amp and speaker combinations but I really enjoy what I hear.
Thank you Carlos.
Ryan
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Many thanks to you by your kindness to publish pictures and to write your evaluation
Nice work, beautifull construction, awsome boards dear RKH.
Keep the good mood, go enjoying forum nice amplifiers and share all them with us.
Needing anything, go to my direct email adress:
nanabrother@hotmail.com
regards,
Carlos
Nice work, beautifull construction, awsome boards dear RKH.
Keep the good mood, go enjoying forum nice amplifiers and share all them with us.
Needing anything, go to my direct email adress:
nanabrother@hotmail.com
regards,
Carlos
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