handheld oscilloscope Help!!!

[noeg]

Just started to seek for a handheld oscilloscope ($300 usd max).Just needed for gain adjusting on my amps,testing resistors,capacitors etc.rather than using a digitalmultimeter...I have come across with a Velleman hps40 and tpi 440 scopeplus ,both handheld.Need input from you guys,kinda newbie here,any suggestions?

[ttocs]

just out of curiousity, have you considered seeing if your local audio shop has a meter and what they charge to tune a system with it? Your not going to be using it to measure resistors or caps and it is something that unless you have a die-hard need you will only pull out 3-4 times before you do not need it anymore.......

[oldskoolmseriesfan]

just out of curiousity, have you considered seeing if your local audio shop has a meter and what they charge to tune a system with it? Your not going to be using it to measure resistors or caps and it is something that unless you have a die-hard need you will only pull out 3-4 times before you do not need it anymore.......

It would still be cool to have one on hand

[noeg]

Just happy to have one handy,im allways trying other amps and would like to have them set just right,other forums and you tube point to an oscilloscope for best gain results and avoid amp clipping,im also considering an owon 5022s digital oscilloscope,im not to hot about the old school big box oscilloscopes.I have a UEI dmm if i need to test transistors,etc.

[Eric D]

If you buy a non hand held style, I suggest you get a differential probe for it is well. If you end up connecting the ground on the scope to an active lead on the amp, you will likely kill the amp.

[ttocs]

I am happy to see someone going the extra mile to make sure it is done right but there have only been a few occasions that dictated the need for a sillyscope to the point that I have never bought one. On the few occasions I needed one I have a buddy that has one. I am willing to bet if you ask any pro installer how many times he has needed to use one you would be suprised the answer would not be much different.

your ears are really your most valuable tool in this biz.

[Eric D]

I am happy to see someone going the extra mile to make sure it is done right but there have only been a few occasions that dictated the need for a sillyscope to the point that I have never bought one. On the few occasions I needed one I have a buddy that has one. I am willing to bet if you ask any pro installer how many times he has needed to use one you would be suprised the answer would not be much different.

your ears are really your most valuable tool in this biz.

Maybe if your "biz" is working at Best Buy...

[ttocs]

the shops I worked at in phoenix did mainly high-end systems. They were not too much into the competition scene but they had more then a few crazy audiophiles with checkbooks.

I have tuned all of my systems by ear and I guess that makes them just barely above bby's quality ......

[Eric D]

So prove it then...

All you have proven is you don't know how to use an o-scope, and therefore you are completely against them. I don't understand how you can be so against something you don't even understand without ever trying it.

It is senseless to spend $600 on a deck, $150 on a line driver, $400 on an EQ, and who knows what on amps, then expect to actually get it right setting it by ear.

Sure you can adjust a deck and single amp by ear like you did back when you worked for Best Buy, but this is not Best Buy. People here want to get what they pay for and they want things set right. Go back to the big box stores where you belong.

[ttocs]

wow, dude chill the heck out. I have a degree in electronics and worked in some of the most state of the art semi-conductor manf facilities of the time as a technition so I am not sure how you expect me to show I know how to use a scope. Between school and two different careers that used it I am willing to bet I have had my hands on them just as much if not more then you if you want. I am also not sure why you think him with 6 posts would know how to use one to be effective, or have the system that needs one to use. He said he wants to check caps and resistors with it.............. I have learned the difference between what is needed and what is not and 99% of the average systems(maybe %50 on this site) have no need to tune their system with a scope.

I am just trying to tell the guy that depending on what he has, $300 can often be spend on SOOO many other and better things if it is audio or not. I don't hate scopes but I have no idea what yer deal with me is.

[gbody805]

Spelled -Technician- man.

Sorry my bad.
Carry on

[ttocs]

you would be well off for me to do your math homework or hook up your system or type something for you(50wpm) but don't cheat on me on a spelling test . When I care about something enoug to make sure it is spelled properly there is a tool for that that I also know how to use. You are welcome to keep correcting each of my spelling posts if you want, hope you have time on your hands.

Have I said welcome to the forum Gbody? strange huh

Feel free to spell check this one and consider that your welcome.

[Eric D]

wow, dude chill the heck out. I have a degree in electronics and worked in some of the most state of the art semi-conductor manf facilities of the time as a technition so I am not sure how you expect me to show I know how to use a scope. Between school and two different careers that used it I am willing to bet I have had my hands on them just as much if not more then you if you want. I am also not sure why you think him with 6 posts would know how to use one to be effective, or have the system that needs one to use. He said he wants to check caps and resistors with it.............. I have learned the difference between what is needed and what is not and 99% of the average systems(maybe %50 on this site) have no need to tune their system with a scope.

I am just trying to tell the guy that depending on what he has, $300 can often be spend on SOOO many other and better things if it is audio or not. I don't hate scopes but I have no idea what yer deal with me is.

You have nothing to back any of this up. You could be just making this stuff up.

Your track record establishes only two things I can think of...

1) You don't really understand what an o-scope is for or how to use it.

2) You think any amp made is Asia is automatically junk, no mater what its specs, measurements, reliability or SQ is.

Point 2 just reinforces point 1. If you realized where something is made has nothing to do with how it performs, you would realize that test equipment is more accurate than human ears can ever be.

Hell, I bet in your wonderland of "golden ears" you don't need a RTA either? Sure, you just set your 30 band EQ by ear and go win trophies.

[stipud]

I guess the issue here is that we can't really tell if your claims are true or not because we can't hear your stereo. Claiming you have golden ears that can set gains to the same tolerance as an oscilloscope would take quite a leap in faith to believe otherwise. And it's not like you're the only one who claims to have golden ears either, there are plenty of ignorant folks online who do the same thing. This only adds to my skepticism.

What I disagree with the most is that you argue against the use of DMMs and Oscilloscopes by OTHER PEOPLE, who may be totally deaf. Even if you did have golden ears, this would still not apply to other people. So anecdotally you MAY be right in your own case, but objectively there's little substance to your claim. On the contrary, using a DMM or even better, an Oscilloscope to set your gains is something that is an objectively repeatable and measurable way to do it properly, regardless of the circumstance.

I would be curious to see you set the gains by ear on music, and then test them afterwards with an oscilloscope or DMM to see how far off you are. If, on several different installs, you came within 5% of full RMS power, I would be ok with you having your own personal bragging rights about how good your ears are. This still wouldn't validate your claim that other people should follow suit as well.

[ttocs]

ah fuck it buy a scope and enjoy using the 5-6 times you get the opportunity. I am sorry that you are not able to hear my my system through my "golden" ears but lets go back over the key points here.

Noeg got on here wanting advice on which scope to buy so he can,"adjust amps and test resistors and capacitors" after 6 posts with out giving any info no the sytems he is wanting to tune. I simple tried to let him know that you can have all the equipment in the world but if you do not know how to use it, what good will it do you? I simple wanted to know a lilttle more about him and his system and what he does to find out if he reall needed a scope. I think that the average stereo person who has no idea how to use a scope or really what it is for will do much much more damage to a system then setting it by ear. If they do not understand what clipping sounds like how the hell are they suposed to understand it on the scope? You do not just throw the leads on there, push a button and BOOM you have magically tuned your system better then A TRAINED PROFESSIONAL WITH 15 YRS EXPERIENCE......... I am sorry you guys are so jeleous of my "golden ears" as you put it but I can't help that. Keep up the good work, practice practice practice and maybe you will get there one day and be as good as me

Now why you put my thoughts that the asian amps are not as reliable as the old made in america amps just reinforces that you do have something aginst me because of a stupid opinion(two actually, yours and mine ). I actually recieved a pm about your comments and in support of my thoughts on this matter but I guess your "I am right and you are always wrong" attitude has kept him from posting on here. I have no issues with you even though you like asain amps and seem to have some sort of personal issue with me. I question here if your personal issues with me are clouding your judgement on the question asked but I could care less really.

so I will end it by giving up and telling EVERYONE one here that you every person that has ever hooked up ANY stereo will benifit from spending at least $300 on a scope not matter what the circomstance.

Feel free to spell check for me as I did not.

[Eric D]

There is little point in arguing with you when you have so little grasp for what you are talking about.

Average people (not you with your golden ears) cannot hear clipping until they hit 3 or more db of gain overlap. If this clipping starts at the head unit, and makes its way all through the signal chain they will never get their system tuned right.

As for Asian amps, I never said I like them. I like amps that work and perform well. I don't care where they are made. You specifically have posted in the past that the Xenon amps are junk because they are Asian. I feel they are junk due to design flaws, not the location of where they are manufactured. We both agree they are junk, but for two totally different reasons. And I think your reason is pretty ignorant.

If you have 15 years of audio experience, it is clearly 15 years sweeping the floor at your local stereo shop, not actually installing, tuning, or being involved in installing anything.

[ttocs]

wow, just wow. I am not sure why you keep attacking and belittleing me when I have not done anything to deserve it but that is behind me now. You are right, I answered phones, swept the floors and took out the trash for all those years in the shop. I never actually touched a wire, scope or even a toolbox. I have a degree in electronics but never actually read a book or understood anything about it because I was blessed to sit next to a person like you that could walk on water. I am a hack compaired to your holy ability to know EXACTLY what is going on everywhere with out asking any qualifying questions. I am ignorant in your shadow and a tool on top of it that would just be lucky to sweep your floors and take our your trash. And if you believe all of this you are 10x more ignorant that anyone that has ever come on here and that is only belittled by your ability to be a complete and total ass but I am sure you have not heard that before huh? I guess I will stoop to your level and let the insults fly, the other approach just seems to have got you all riled up.....

Since you must know what qualifies me to have an expert opinion in this area I will go ahead and do it as long as you post yours. I would be happy to start a post were we can compair and see who's audio dick is bigger if that is what you want but to be honest I could care less as I KNOW that while I know alot, I do not know alot. You on the other hand know everything and we are just lucky that you can bestow your knowledge on us. So if I post my resume, and you then get to call all my references would that mean anything to you? I want to call yours as well...........

I just think that the "average people" that you mentioned above would be 10x better off trusting their ears then another piece of equipment they do not understand how to use and will not read the manual to understand. I am not saying that he should not buy one or will not have a need for one but just that we do not know enough about him or his needs to say that he should go blow $300 on one. I was trying to find out before you started calling me names.........

Maybe we can get a group buy together since the average person needs one! You again made reference to the average person but I will say that the "average person" has no need for a scope to tune an "average system". I was trying to find out if he was above average before I made any recomendations.

Next time you want to pick a fight with me just take it over to a pm, I am done with this pissing match since I have now stooped to your level and started calling names. I am better then this for sure but when I need to call a spade a spade I will.

[stipud]

Eric, I have to agree that you are pushing a few boundaries here. I don't want to see this get into strawman arguments and personal attacks; that would be a waste of a good discussion. Belittling your opponent rather than attacking their argument is a poor foundation for debate, and only weakens your point.

On the same token your point also lacks substance Scott. You use your electronics degree, shop experience, etc. in support of your argument, without much else to back it up. Basically what this comes out as is "I am more educated than you so I know better", which is exactly what you are accusing Eric of doing as well.

So let's not lose our cool here, and keep the debate civil and on topic.

Now I can count the number of times I have needed to use my RTA on one hand. But I still consider it a worthwhile investment, because I can measurably set my EQ properly, and visibly see the results of my modifications. Sure, you could tune it by ear, and you might somehow through luck or damn good ears be able to tune it as well as the RTA can, but odds are very high that you can't.

Same thing applies for the oscilloscope/multimeter. Maybe you can hear clipping at 1dB, and get your gains set perfectly every time. But with a multimeter or oscilloscope, anyone can see and measure your changes. Clearly you can see this HAS to be the superior method, ignoring things like cost, education, etc.

I think we should come up with a list of the pros and cons of each option. Then we can weigh them out.

Setting gains by ear
Pro:
- Cheapest
- Works ok if you have good ears and know what a good system actually sounds like
Con:
- Most people don't know what a reference system sounds like, and can't hear clipping until it is way over the limits
- Will almost always be a margin over or under the output limit of the amp, which would shrink depending on your tuning skills

Setting gains by DMM
Pro:
- Cheapish
- Sets gains very accurately to a certain point
Con:
- If the output rating is overrated, you could clip
- Doesn't maximize the possible gain level, assuming your amp is underrated. However, this will always be at a SAFE level, and within the margin of headroom, so I don't consider this a big con.

Setting gains by Oscilloscope
Pro:
- Sets gains perfectly and measurably every time
Con:
- Expensive

Feel free to add or discuss points as you see fit.

[ttocs]

where have I ever said that I can tune a system better then a scope, or an RTA(which is new in this discussion now)? I am saying that after tuning hundreds of amps over my years that I can do it better then the average person. If eric is the average person and takes offence to that the screw 'em.

We have had the multi-meter conversation many times and I still bite my lip when it is mentioned as I think there is too much variance between the average meter and a good one and again it is only as good as the tool using it.

I am once again saying that the average music person, and maybe %50 of the people that call themselfs audiophiles will do just fine setting them by ear. Do you think that if I was able to tune it with in %5 of perfect, that you would be able to hear the %5 after the tune? I would argue that the average person would not have any idea till well after %10 and alot of us would not be able to tell either.

[ttocs]

On the same token your point also lacks substance Scott. You use your electronics degree, shop experience, etc. in support of your argument, without much else to back it up. Basically what this comes out as is "I am more educated than you so I know better", which is exactly what you are accusing Eric of doing as well.

do you realize how funny that statements is since he was asking me to prove how I know what I am talking about? my years spent in the install bay and in the classroom is what allows me to say my words do not lack substance. If I need to post my grades to show get the substance I am requesting I can show that I graduated with honors near the top of my class but otherwise I am not sure what it takes to get any respect here or show you know anything.


"I am more educated than you so I know better" - while this is not always the case, wouldn't we agree that more often then not the educated person does know more as long as the discussion is about the topic one is educated in/on?
I am not sayin I am harvard educated but I have studied this stuff literally and been tested on it so maybe that is why I feel like I know what I am talking about.....

[Pillow]

... Damn this is rough thread! Peace guys.

IMO for the average joe, the DMM is the best way. Tom's thread on the proper procedure is golden. The flaw with this is that if the HU is clipping... Everything downstream is effected negatively. I have heard mixed reviews on manufactures specs for RCA output voltage, which makes it impossible to test with a DMM due to bad data.

Here is what I would recommend for an average joe. Go to a local shop or find a friend that has an O-scope and pay them for the service. Depending on your area some local clubs will have a test-n-tune weekend.

If you actually plan to use an o-scope regularly then buying one is a good option. I think BCAE site has a good article on what is needed for CA use, which is fairly low rent compared to the Cadillac models for scientific use.

[ttocs]

I agree with almost everything that has been said above and I am sorry that I was part of this negative post. I sent eric a pm to try and work it out......

[stipud]

where have I ever said that I can tune a system better then a scope, or an RTA(which is new in this discussion now)? I am saying that after tuning hundreds of amps over my years that I can do it better then the average person. If eric is the average person and takes offence to that the screw 'em

I was using the RTA as similar example of how a tool can be used to help. A DMM and Oscilloscope is no different; they all allow you to measure what your stereo is doing.

So only after tuning hundreds of amps, you think you can do it better than the average person. Why, then, do you suggest that average people tune their stereo by ear? Clearly this contradicts your point of having years of experience necessary to do so.

We have had the multi-meter conversation many times and I still bite my lip when it is mentioned as I think there is too much variance between the average meter and a good one and again it is only as good as the tool using it.

The calibration can be confirmed on a reliable source, like a power outlet or battery. Regardless I think the possiblity of cheap instruments being out of calibration is besides the point of which one is superior for measurement of your speaker gains. The question we are trying to answer here is WHAT IS THE BEST TOOL TO MEASURE GAINS? Is it your ears, a dmm, or an oscilloscope?

I am once again saying that the average music person, and maybe %50 of the people that call themselfs audiophiles will do just fine setting them by ear. Do you think that if I was able to tune it with in %5 of perfect, that you would be able to hear the %5 after the tune? I would argue that the average person would not have any idea till well after %10 and alot of us would not be able to tell either.

No, people can't make out a 5% difference in gains. That only bolsters my point that a DMM is a worthwhile tool because it always puts you in a good, safe range. It's not "perfect" like an oscilloscope, but it usually gets you so damn close you would not have heard the difference in the first place. Where an oscilloscope is vastly superior compared to a DMM is when the power ratings are inaccurate (and if overrated, tuning by ear is probably better too).

I thought you needed 15 years of experience tuning amplifiers to be able to do them by ear? Now you suggest that 50% of people can do this just as well as you? I highly doubt that. Most installs I have heard where some newbie decided to tune it themselves had cranked gains and severe clipping. Is this contrary to what you have seen? Do you really have that much faith in the ignorant consumer who thinks the gain is a volume control?

[stipud]

do you realize how funny that statements is since he was asking me to prove how I know what I am talking about? my years spent in the install bay and in the classroom is what allows me to say my words do not lack substance. If I need to post my grades to show get the substance I am requesting I can show that I graduated with honors near the top of my class but otherwise I am not sure what it takes to get any respect here or show you know anything.


"I am more educated than you so I know better" - while this is not always the case, wouldn't we agree that more often then not the educated person does know more as long as the discussion is about the topic one is educated in/on?
I am not sayin I am harvard educated but I have studied this stuff literally and been tested on it so maybe that is why I feel like I know what I am talking about.....

If you are an expert, use your expertise to argue facts which bolster your point. Don't use your degree, grades or job experience in defense of your point, because on their own they have nothing to do with the debate. You must use the knowledge, which you gained through your experience, to back up your point. This argument sums up as... I have 15 years of install experience and a degree in electronics with honors, therefore using your ears is the superior way of measuring gains. Do you see what I mean about lacking substance?

The problem is your claim of using ears as a measuring tool is not something that can be objectively or empirically proven to be accurate, while a DMM and Oscilloscope can be. A deaf person would not be able to set gains by ear, but they could use an Oscilloscope just fine.

You have claimed that your years of experience is what allowed you to be able to set gains by ear. I have no problem with that. The only thing I disagree with is that you frown upon other people using DMMs and O-scopes, when they in all likelihood cannot set gains by ear as accurately as you claim to be able to. With 15 years of installing under your belt you should know that the average joe consumer should not be trusted with his own stereo. Hell when I started I probably did more harm than good with my gains as well. By learning how to set gains properly with a DMM I started to learn what proper tuning sounds like. Without that knowledge you are just making a stab in the dark at "what sounds best", but that is not necessarily accurate.

[ttocs]

I believe that the average person hardly knows how to hook up his amp, and barely understands the gain and x-over functions of said amp. I have this opinion after watching one person after another come into my shops saying that they know everything and I should hire them only to find that they made their connections with band-aids(true story). Now again I do not believe we have alot of people like that but I think we have a few that might qualify and just need to sit and listen a little more both to the music and to what we say.

Now we expect everyone that comes on here is above that standard, and I think we are expecting too much. Again I was trying to feel out his experience and the system involvled before this was turned around to me proving what I know........

Now the meter thing, great lets beat this dead sucker if you want ok? I have bit my lip long enough. Take into account a cheap meter(they are all the same right?) where we do not know if it is measuring rms or peak voltage, where we do not know if the leads on the meter were worth .02 cents or if they can take an accurate reading. Take into account that this person that does not understand his amps settings but now suddenly understands the meters settings and readings. Take into account that when the peak is reached and it starts to clip that the reading on the RMS meter will only change a small amount so you really do not know. Take into account we are measuring down to the mV most of the tiem and a connection that isn't perfect will be off and just wiggling the leads on the connection can cause it to drift. Take into account that once again the average person can't take the time to read the manual to understand what is going on but is now supposed to do calculation on what the meter will read. Take all of these into account and I think that the average person would be better off saving the cash on the meter and scope and JUST FUCKIN LISTEN TO THE MUSIC FOR CHRIST SAKES.......... they have just as much of a chance of blowing their equipment after spending the cash on a meter or scope if they can't understand that when it starts to sound bad, bad things happen. You guys make it sound to the "average person" that after doing these dances that they will not blow anything and we all know that is wrong.

I do not understand how average person or everyone for that matter cannot hear when a signal is distorted to the point it is doing damage to something and if that give me golden ears then I will keep my sig. You think that the average person has a meter/scope or at a bare minimum will be able to push the power button and off they go.......