This is an upgrade and modification thread. Yes I do have a buzzing problem. The troubleshooting thread for that is here
Hence my ideas on the filtering and sheilding are - as simon says - to do with sound quality only. Simons comments are to do with what he thinks I should concentrate on in terms of improving SQ.
If indeed the right filter can at least not worsen SQ would it serve well to isolate noisy comonents when they are running their own dedicated supply?
PS: 5-1 !!!!!!
Hence my ideas on the filtering and sheilding are - as simon says - to do with sound quality only. Simons comments are to do with what he thinks I should concentrate on in terms of improving SQ.
If indeed the right filter can at least not worsen SQ would it serve well to isolate noisy comonents when they are running their own dedicated supply?
PS: 5-1 !!!!!!
Stream said:Hi all. I'm planing to move into your discussion and make some little tweaks to my 340
1. Swap Opamp to LM4562. It has normal price (about 5$) and doesn't need any adapters. Maybe some time later, i'll offer some BD Adapters and put AD8066 There.
2. Change input Cap to lower value polypropilene (about 1uF).
[optional]: change all decoupling caps to polyp. (no so pricey as Mike's Mundorf,but something cheap as Epcos or our russian k73-17)
3. [Optional]: Tune tone_Control section. Maybe change bass frequency and bandwidth. This part is optional, because i don't use tone all the time, but sometimes I want to set bass pot to about 3 o'clock... I think it's my speakers fault , but as soon as have them, tone controls section is usefull for me.
So who has any ideas how to count bass freq ?
4. Change Main PS Caps to Mike's Stock Caps
[optional] change diodes.
5. [optional]. Insert small +5V powersupply for source_selector section. Do You think that separate small trafo (5VDC 1A) + 78T05 VR + Rubicon MBZ litycs and some small-size polyprop... will slightly improve sound?
P.s. sory for my "broken" English
Simonty, see this thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=130909&pagenumber=1
Hi Stream.
If your using LM4562 the DC offset is so low (im pretty sure) you can get away with just a single decoupling cap per channel but 1uF is probably too small. I plan to replace all the caps in the signal path with wire links exept 2 which will have the Mundorfs somewhere between the input buffer and pots. Aparently pots hate DC. You will need to check for DC at the output to be certain this is ok.
Definately fit my caps when you get them. I would slap those diodes in too. Peter Daniel and Carlos FM both did a lot of testing to find a good diode to work with this family of power chips.
As for the other ideas you have Im not really experienced enpugh to advise you. The transformer idea seems god to me but its a case of doing it to hear what difference it makes. Im going to try it so you could just wait for my report.
What sort of price are Panasonic FC caps in Russia? I read that they are just as good as Blackgate and will be a big improvement over the stock caps. Change the local decoupling at the Lm3886 for sure and change the feedback cap too. If your unsure about changing values just use the same but change to a better quality cap. I would also do the caps either side of the +/- 15v regulators.
Mike.
PS: Post plenty of pics and good luck!
Hi Mike,
What is the purpose of your link? It lead to Greg Ball's commercial site, so I did remove it. He got himself removed from here, so I can hardly allow a link to him and his products. Now it comes back here.
What is the purpose of your link? It lead to Greg Ball's commercial site, so I did remove it. He got himself removed from here, so I can hardly allow a link to him and his products. Now it comes back here.
As I mentioned previously, not the solution I would recommend. However, it is your project and it is once again suffering greatly from "feature creep". Try to pull back and reassess what you actually want to accomplish with this particular amplifier.
This might help actually, depending on what else you do here. Remember that low frequency stuff is dead easy to get rid of, it's the higher frequency stuff that gives us all headaches.
anatech said:Hi Mike,
What is the purpose of your link? It lead to Greg Ball's commercial site, so I did remove it. He got himself removed from here, so I can hardly allow a link to him and his products. Now it comes back here.
Hello Chris,
DIYaudio permits links to many commercial sites/enterprises. Are you saying links to Greg's site are not allowed because of a disagreement that occurred ages ago? Seriously?
I'm on good terms with Greg, by the way, and have heard his angle. However I really couldn't care less - it's history. All that matters now is that Greg produces well engineered, high performance products that many DIYers benefit from. His technical support is also excellent.
He also allows talk about DIYaudio on his site - and why wouldn't he? To do otherwise would be incredibly childish.
Dan
Hi Mike,
What are you telling Stream to do? Buy one of Greg's products? Greg has had his problems at another web site as well, very similar to his troubles here. We will not tolerate having his products pushed - again.
Hi Dan,
Greg and I went through a rough patch. Let's just say that his version of reality and what actually happened are usually very different. I know what he is capable of, but I am not here to air this issue. Nor will I talk about what was in confidence between us. I already know some of what he has said to others though. He has not been truthful from things I've heard from other people.
You know, I dislike very few people. I did not dislike Mr. Ball either, until he pulled some beauties here. I was working hard to keep him a member in good standing too! Anyway, now I am distrustful of him.
Now for what is known. Greg had the problem of always pushing his designs and ideals, no matter what a thread was discussing. Endless salesmanship. This was the root of his troubles. Now, we are too finicky? Well, DiyHiFi had to get rid of him too - for the same reason.
Now check this out. Greg cried when we were going to confine his sales pitches to a free vendor thread. He refused. So he goes over to DiyHiFi and what do we see later on? He's in his own vendor thread, the same thing we wanted! True to form, he then pushed his amp whenever he could to a point where he wore out his welcome there as well.
The upshoot of all this is simple. We will not allow the forums to be used as a sales tool for Greg, or anyone else. He was not persecuted here in any way, but he did take advantage of people's normal kindness. That includes mine.
Look, you want to see someone who supports DIY? Nelson Pass comes to mind. How about everyone else who has developed amplifiers here on this site? Those people support DIY by helping people learn, free of charge.
The claim that Greg Ball is a boon to DIYers does not ring true at all. Re-evaluate the reality by looking around. The man only has a commercial interest, wake up people!
Notice that I never did say he didn't make a good sounding amp. However, it is not the best amp either. I don't know if there is a "best amp" in existence to be honest with you.
Now Dan, if you feel I've been unfair to Greg or his products, please feel free to contact me. The email button is right there. I will not think any less of anyone who does disagree with my views on this. Just as long as everyone is truthful. Greg also has my email address and can contact me directly at any point.
Let's move on to the topic at hand. No more linking to Greg's web site. That will not serve any purpose but to advertise. Any more links to his site will be deleted. That will include links to threads here contain posts that link to his site.
Notice that the DiyHiFi links to Greg are dead now. Seems like someone else had the same issues.
-Chris
What are you telling Stream to do? Buy one of Greg's products? Greg has had his problems at another web site as well, very similar to his troubles here. We will not tolerate having his products pushed - again.
Hi Dan,
Greg and I went through a rough patch. Let's just say that his version of reality and what actually happened are usually very different. I know what he is capable of, but I am not here to air this issue. Nor will I talk about what was in confidence between us. I already know some of what he has said to others though. He has not been truthful from things I've heard from other people.
You know, I dislike very few people. I did not dislike Mr. Ball either, until he pulled some beauties here. I was working hard to keep him a member in good standing too! Anyway, now I am distrustful of him.
Now for what is known. Greg had the problem of always pushing his designs and ideals, no matter what a thread was discussing. Endless salesmanship. This was the root of his troubles. Now, we are too finicky? Well, DiyHiFi had to get rid of him too - for the same reason.
Now check this out. Greg cried when we were going to confine his sales pitches to a free vendor thread. He refused. So he goes over to DiyHiFi and what do we see later on? He's in his own vendor thread, the same thing we wanted! True to form, he then pushed his amp whenever he could to a point where he wore out his welcome there as well.
The upshoot of all this is simple. We will not allow the forums to be used as a sales tool for Greg, or anyone else. He was not persecuted here in any way, but he did take advantage of people's normal kindness. That includes mine.
There was no disagreement, and our guidelines have not changed. Time is entirely irrelevant here.
That is completely unknown. His designs are a heavenly secret and he did not see fit to assist DIYer's to benefit from the knowledge. He only wanted to sell a product. Period. BTW, some people have gone back to other DIY amps and commercial amps.
That, I have no problem with. But this has exactly zero to do with DIY. The man is selling a kit and will not divulge any details unless you buy one and promise not to talk about the design. Even commercial designers will make this information available.
Look, you want to see someone who supports DIY? Nelson Pass comes to mind. How about everyone else who has developed amplifiers here on this site? Those people support DIY by helping people learn, free of charge.
The claim that Greg Ball is a boon to DIYers does not ring true at all. Re-evaluate the reality by looking around. The man only has a commercial interest, wake up people!
Notice that I never did say he didn't make a good sounding amp. However, it is not the best amp either. I don't know if there is a "best amp" in existence to be honest with you.
Now Dan, if you feel I've been unfair to Greg or his products, please feel free to contact me. The email button is right there. I will not think any less of anyone who does disagree with my views on this. Just as long as everyone is truthful. Greg also has my email address and can contact me directly at any point.
Let's move on to the topic at hand. No more linking to Greg's web site. That will not serve any purpose but to advertise. Any more links to his site will be deleted. That will include links to threads here contain posts that link to his site.
Notice that the DiyHiFi links to Greg are dead now. Seems like someone else had the same issues.
-Chris
Stream said:
Stream said:
Are you aware that changing the input capacitor to a lower value will move your lower f(-3) up? This may be welcome to relieve your speakers from energy at frequencies they cannot reproduce. On the other hand this might bring your bass performance even further down.
"Hi Mike,
What are you telling Stream to do? Buy one of Greg's products? Greg has had his problems at another web site as well, very similar to his troubles here. We will not tolerate having his products pushed - again."
Chris.
Like I said, I was trying to help Stream with a possible soloution to his bass problem.
Now please stop ruining my thread with politics and nit picking. Whos moderating you?
Sincerely,
Mike.
What are you telling Stream to do? Buy one of Greg's products? Greg has had his problems at another web site as well, very similar to his troubles here. We will not tolerate having his products pushed - again."
Chris.
Like I said, I was trying to help Stream with a possible soloution to his bass problem.
Now please stop ruining my thread with politics and nit picking. Whos moderating you?
Sincerely,
Mike.
I completely disagree with the Moderator's actions in censoring any and all links to products and services proferred by Greg Ball.
Either we ban ALL links beyond DIYaudio addresses or we ban none, with the exceptions of illegality and pornography. These and other reasons are probably already adequately covered in the Forum's rules.
Past history and behaviours between individuals on this Forum should not influence censorship policy.
Can we have a view from ALL the Moderators on censorship policy?
Does this collective view vary from the published "rules"?
I am starting a new thread to open up this topic.
I wonder if the Moderators will close it or even remove this post to Texas?
Either we ban ALL links beyond DIYaudio addresses or we ban none, with the exceptions of illegality and pornography. These and other reasons are probably already adequately covered in the Forum's rules.
Past history and behaviours between individuals on this Forum should not influence censorship policy.
Can we have a view from ALL the Moderators on censorship policy?
Does this collective view vary from the published "rules"?
I am starting a new thread to open up this topic.
I wonder if the Moderators will close it or even remove this post to Texas?
Hello Chris,
I'd assumed that you wouldn't want to drag up what happened with Greg, yet you've chosen to revive your issues with Greg, and very publicly criticized him and his character. You've also said a number of things about him that I know not to be true.
Fact: Greg offers loads of help to other people with design insights gained through his experience. He has done it here, at DIYhifi and at his own forum. I'm talking about helping people develop their own designs as well as modify Greg's own. I could post links to numerous examples, but there's no point as they would just be taken down.
Chris, being a mod, you can do whatever you feel like. But whatever has happened between the two has caused you to have a very coloured view of him. Your policy of banning links to his site is unfair and inconsistent.
By the way, DIYhifi has plenty of it's own issues, and I'm disappointed that you so very freely throw around half-truths with the intent of damaging someone's character.
Dan
I'd assumed that you wouldn't want to drag up what happened with Greg, yet you've chosen to revive your issues with Greg, and very publicly criticized him and his character. You've also said a number of things about him that I know not to be true.
Fact: Greg offers loads of help to other people with design insights gained through his experience. He has done it here, at DIYhifi and at his own forum. I'm talking about helping people develop their own designs as well as modify Greg's own. I could post links to numerous examples, but there's no point as they would just be taken down.
Chris, being a mod, you can do whatever you feel like. But whatever has happened between the two has caused you to have a very coloured view of him. Your policy of banning links to his site is unfair and inconsistent.
By the way, DIYhifi has plenty of it's own issues, and I'm disappointed that you so very freely throw around half-truths with the intent of damaging someone's character.
Dan
there is a point in extending the frequency response of the amplifier to far wider than you might expect the speaker to be able to reproduce.
It sounds more natural.
I use F-1dB~=3Hz.
This seems to work for me.
The formula for the high pass filter (DC blocking cap) is
F-3dB = 1 / 2 / Pi / RC timeconstant.
RC time constant is the product of the series cap in Farads and the grounding resistor that follows in ohms.
i.e. 1uF and 20k gives F-3dB=7.96Hz.
F-1dB ~=2 * F-3dB ~= 16Hz.
The rest of the amplifier must be designed to pass this frequency. i.e. the input filters must limit the bandwidth.
It sounds more natural.
I use F-1dB~=3Hz.
This seems to work for me.
The formula for the high pass filter (DC blocking cap) is
F-3dB = 1 / 2 / Pi / RC timeconstant.
RC time constant is the product of the series cap in Farads and the grounding resistor that follows in ohms.
i.e. 1uF and 20k gives F-3dB=7.96Hz.
F-1dB ~=2 * F-3dB ~= 16Hz.
The rest of the amplifier must be designed to pass this frequency. i.e. the input filters must limit the bandwidth.
Hi Mike,
What the bassXT is is a simplified version of what is found in even inexpensive car power amps. Nothing special, although it's not the best for ported speakers. You need to be aware that below the speaker systems resonant frequency, the woofer becomes unloaded and increasing the bass below that point is ill advised. This will work great with sealed boxes. I had a look at it on Greg's site.
There was no reason to respond the way you did however.
Hi Andrew,
I can accept that you disagree with me on this. I fully expected this response from you. The entire reason I will not allow links to Greg is that he tends to get people to do his advertising for him these days. You are fully aware that this was the main issue he had with this place. There are other vendors of kits and information around. Regardless of how your friendship is with Greg, even you have to agree that we have to keep the forums clear of focused commercial interests. Anyway, allowing Greg to advertise here by any means goes against our previous efforts to stop this.
-Chris
What the bassXT is is a simplified version of what is found in even inexpensive car power amps. Nothing special, although it's not the best for ported speakers. You need to be aware that below the speaker systems resonant frequency, the woofer becomes unloaded and increasing the bass below that point is ill advised. This will work great with sealed boxes. I had a look at it on Greg's site.
There was no reason to respond the way you did however.
Fully agree. I've done this in the past. The trick is to be able to control the impedances so your cutoff is where you expect it and stable. Often that means swamping the normal impedances with lower ones or buffering the input to a point where your impedance can be controlled.
Hi Andrew,
I can accept that you disagree with me on this. I fully expected this response from you. The entire reason I will not allow links to Greg is that he tends to get people to do his advertising for him these days. You are fully aware that this was the main issue he had with this place. There are other vendors of kits and information around. Regardless of how your friendship is with Greg, even you have to agree that we have to keep the forums clear of focused commercial interests. Anyway, allowing Greg to advertise here by any means goes against our previous efforts to stop this.
-Chris
Hi Dan,
Guys, my only intent is this. Greg Ball had problems here, mostly due to his use of his membership was to advance his own commercial interests. The one and only reason I object to links pointing to his web site and products is that in effect, this allows him to continue to abuse our site to advance his own interests as before. There is no personal agenda or vendetta involved.
Now, the case is closed. We can argue about this via email if you so desire. Finally, I know you all disagree with me on this. That's okay too.
-Chris
I've only said what was in fact true. You obviously don't know him as well as you think. I have not revealed some other things that would be less palatable as they were between Greg and I.
Where in public has Greg revealed any details of his own designs? That was one of the problems we had. He maintained his designs were superior to all others and always refused to discuss his circuit. His "help" to others had a steep price attached. That was constant advertising of his own "superior" products. Most members here are far more helpful that Greg ever was. And they don't sell anything.
Actually, no I can't. The moderating team is something we all have to answer to, including myself. What I am doing here is in fact very consistent. He was not banned, his account is disabled. This was a decision made by the entire moderating team, not me. Sadly, I was working to keep Greg. Imagine that! Greg forced our hand in the end. I guess he didn't tell you how hard I was working to keep him eh? I guess my view is coloured. Just not the way you assumed. If you did hear differently, other moderators here can confirm this and you were misled. I would not be surprised.
So what half truth did I put forward? Did Greg have his own little selling spot over there? I know for a fact that he did. In fact, links here pointing to those threads at DiyHiFi are now dead. Check. Please. Is Greg still a member there? I don't know what the exact issues were, but I also know he isn't a member. I will accept that I might be mistaken on something, but the intent was not malicious at all.
Guys, my only intent is this. Greg Ball had problems here, mostly due to his use of his membership was to advance his own commercial interests. The one and only reason I object to links pointing to his web site and products is that in effect, this allows him to continue to abuse our site to advance his own interests as before. There is no personal agenda or vendetta involved.
Now, the case is closed. We can argue about this via email if you so desire. Finally, I know you all disagree with me on this. That's okay too.
-Chris
You should expect people to be annoyed when their gunuine attempt at helping somone find a soloution, is made out to be somthing else by a third party. You made me wrong for helping somone - that is not ok. Regardless of the argument between DIY audio and Greg, Im annoyed by that. Now what if somone else who owns a 340A finds this thread and begins to enthisiastically read on? Do you think they will feel the same way after reading through? My viewpoint is that they will be less likely to post due to the 'overpolicing' here.
I must admit you seem to really know your stuff. You have made several interesting and enlightening posts here. Im gratefull for that. However, you also are very quick to shoot down other peoples ideas. Wheteher right or not, people deserve to know that 'what is real for them - is real for them'. Cast your mind back to the last time you thought you were right about something and somone made it wrong. how did you feel? Now imagine (as an example) if all of your concepts and ideas on one particular subject were picked apart and invalidated? Wouldnt you feel sort of supressed on the subject? Would you want someone else to feel that way?
Of course while writing these words I am aware that you are genuinely trying to help, and my words above could be considered to make you wrong. Well, no. I am simply asking that you consider holding back on the 'dont do this' or 'that would be pointless on this project' type of comments. Instead encourage people to try their ideas, regardless of your own opinion. What is true for you - is true for you. And so it goes for everyone else on this planet. If a suggested mod proves to give no benefit or indeed worsens the item, then at least the member has learnt this from his own experince. Which gives him far more certainty than somone else's advice or opinion ever could. On the other hand the said mod could be a raging sucess! You would never really know for sure wothout trying it with the very same peice of equipment would you?
At the end of the day you can see that I am very enthusiastic about modding Hi-Fi and my approach is far from conservative. If I blow the thing up, so be it, its mine to blow up. If I waste money on boutique parts, so be it, its my money to waste. If I have an idea that 'this tweak' I thought of will work, then so be it if it does or it dosent. Its my idea and you should NEVER supress someones ideas.
My comment "Whos moderating you?" was meant utterly. If you read and consider my thoughts above you will see what Im getting at. Also, now that you know my viewpoint you might better understand why I got annoyed with you earlier in this thread.
Lets keep things positive!
Much love.
Mike
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