Oh you just can't imagine how fed up I am with this thing and how impatient I am to see it go out the door...
No high volume for me ! The buyer will find out.
I test at low levels, that I can stand. How many 303 sellers bother scoping the output, measuring the amplification and check the waveform ?
None that I saw. I am already well above the average seller here, I don't feel guilty ! Sorry !
100mVpp and that gives me 4.0Vpp at the output,and it's already quite loud as it is to be honest !
I don't see why anyone would try to use anywhere near the max power of this amp, unless he wants to lose his hearing, it's pure madness.
You are missing the point.
No high volume for me ! The buyer will find out.
I test at low levels, that I can stand. How many 303 sellers bother scoping the output, measuring the amplification and check the waveform ?
None that I saw. I am already well above the average seller here, I don't feel guilty ! Sorry !
100mVpp and that gives me 4.0Vpp at the output,and it's already quite loud as it is to be honest !
I don't see why anyone would try to use anywhere near the max power of this amp, unless he wants to lose his hearing, it's pure madness.
The real loudness will vary of course depending on the sensitivity of the speakers being used. Most true Hi-Fi speakers will require a relatively high output wattage to deliver much volume, whereas speakers from a say a average domestic music system are high sensitivity, because they are designed to make the most in terms of sound level from very low output wattage amplifiers. This why such systems normally steer well clear of giving any real specifications that mean something. Normally they will quote output power with either Peak watts or Music Power Watts and Hi-Fi will always quote it in terms of RMS watts with low level of distortion, but other sound system have a far higher level of distortion and noise levels.
You are missing the point.
Really ? Your probe point missed its mark, did it not ?
Better tools and better techniques save us all immense amounts of grief and time.
However I am not too sure what these two 0.3R do.
Thanks Spec !
OK I went for the 3x0.1R in series option. Just soldered that in place, quick test..... driver board is back alive !
NO MORE PROBING on this amp now !
Tomorrow I will order the transistors.
The smell of victory is getting stronger ans stronger !
Whatever money I get for this 33/303 pair, it will be well deserved !
Oh, forgot... it goes without saying that I don't feel comfortable playing around with low value WW resistor and NOT even be able to actually meeasure them accurately !
A 4 wire capable bench DMM is on the cards, has been for a long time.
For now I make do with my Fluke 11. Has a 0.1 ohms resolution, and I know for a fact that it's voltage and resistance measurements are way more accurate than it's advertised spec of... horrible %.
So I short the leads, get a solid / stable 0.2 ohms, then when I measure my 0.1 resistors I get a solid 0.3 ohms reading on the display, which is better than no test at all, but still I dream of 4 wire measurements in the lab, regularly !
...
Interesting. So you mean a 100W hifi speaker will actually be much less efficient than a 100W cheap speaker ? It will convert less of that 100W into actual sound pressure, and more into heat dissipated in the speaker coil ?
Interesting. So you mean a 100W hifi speaker will actually be much less efficient than a 100W cheap speaker ? It will convert less of that 100W into actual sound pressure, and more into heat dissipated in the speaker coil ?
Interesting. So you mean a 100W hifi speaker will actually be much less efficient than a 100W cheap speaker ? It will convert less of that 100W into actual sound pressure, and more into heat dissipated in the speaker coil ?If you check out the magnets on the speakers, you will notice that cheap speakers will have far smaller and less powerful magnets than those on decent quality Hi-Fi speakers. This means that Hi-Fi speaker requires more wattage to produce enough energy in the voice coil to overcome the effect of the strong magnet.
If you check out the magnets on the speakers, you will notice that cheap speakers will have far smaller and less powerful magnets than those on decent quality Hi-Fi speakers. This means that Hi-Fi speaker requires more wattage to produce enough energy in the voice coil to overcome the effect of the strong magnet.
The large speakers used in the late 1950s & '60s had very large magnets, & were efficient, plus were used in massive, efficient enclosures.
Boooooo.
I'm trying to get sticky labels to label all the 3.5" floppy disks I'm using for my test gear and retro PC, BUT.... Of the two Japanese brands of labels that are advertised for floppy disks (one being a 3M brand...) BOTH turned out to be complete crap and do their best to peel themselves off the disks within minutes of sticking them down. Turns out the adhesive is 'temporary adhesive for easy removal', completely the opposite of what you want for labelling disks..... Complete crap.
So, a check of Amazon.com found me some Avery 2" x 2-3/4" sticker labels with strong adhesive, and says they will ship them to Japan, and even gives a shipping cost (not terrible), perfect I'll get those.
Nope! Amazon says they'll ship these to Japan in the search results page and in the actual listing but when I go to pay, it says NOPE, no shipping to Japan for YOU!. BOOOOOOO!
Anyone want to do me a shipping favour?
You don't need to have 4 wire capability, all you need is a decent 2 wire meter with a Null function, short the leads together, press the null button and it will reset the display to read zero, then measure your .3ohm resistor and your meter will display .3ohms. A 4 wire meter is just spending more money, unnecessarily.
Else it would be crystal clear that everyone should have at least one desk multimeter with 4 wire capability AND that the requirement to measure resistances below 1 Ohm is a perfectly good reason to aquire a milli/micro-Ohmmeter!
You don't need to have 4 wire capability, all you need is a decent 2 wire meter with a Null function, short the leads together, press the null button and it will reset the display to read zero, then measure your .3ohm resistor and your meter will display .3ohms. A 4 wire meter is just spending more money, unnecessarily.Ok, the URL seems to suffer from malignous redirection and some flunkie is posing as our friend Specmaster here!
Else it would be crystal clear that everyone should have at least one desk multimeter with 4 wire capability AND that the requirement to measure resistances below 1 Ohm is a perfectly good reason to aquire a milli/micro-Ohmmeter!
You don't need to have 4 wire capability, all you need is a decent 2 wire meter with a Null function, short the leads together, press the null button and it will reset the display to read zero, then measure your .3ohm resistor and your meter will display .3ohms. A 4 wire meter is just spending more money, unnecessarily.Ok, the URL seems to suffer from malignous redirection and some flunkie is posing as our friend Specmaster here!
Else it would be crystal clear that everyone should have at least one desk multimeter with 4 wire capability AND that the requirement to measure resistances below 1 Ohm is a perfectly good reason to aquire a milli/micro-Ohmmeter!Nope it is I alright , but I was under the distinct impression that Vince was looking to raise some Euro's not spend some, and for measuring resistances of the value that he was looking at, there is no need for a 4 wire meter. I have 3 such meters myself and I can't recall ever having to use them in such fashion, 2 wire has always been good enough, especially once the lead resistance has been nulled out of the readings. I like to only really buy what I need, but then again, I'm not in the same position of a lot of friends here who are single, I have to keep SWMBO happy as well
On another note, some good news : after much delay and fear of getting lost or damaged... I finally, finally received my Rochar Niksee DMM type A.1466 !!!
It was well packaged but still there is some minor metal work needed : front top right corner of the top cover (see close-up shot below) is out of shape. It's totally inconsistent with a shipping damage, given the way that it was packaged. Still, didn't notice it in the sellers pictures.... but for 10 Euros the thing, complete and in good overall nick other than being super dirty.... I am still over the moon, so happy to have secured this puppy !
Will make it look as good as can be of course.
At the back we have a pritner output, cool... especially since this meter has good resolution, 20,000 counts I think, so probably a decent accuracy to match that as well. So would be cool to use it for some data logging.
Also at the back, we see stickers from the " CNES " institute. It's French for " Centre National d'Etudes Spatiales ", the public body that does research related to space stuff.
So pretty cool ! This meter has a nice history.... these stickers are there to stay
One thing that shocked me with this meter, is the big range switch on the right side / plugin.
It is VERY hard to turn and VERY loud ! CLUNK CLUNK CLUNK !!
It feels solid and indestructible for sure !
Either it's intentional or it needs some lubrication.... the truth probably lies somewhere in between...
Sadly I can't play with this thing just yet as the bench is full of QUAD Stuff which I want to 100% finish before I can work on anything else.
So since it will take quite some time before I get to play with it, I wanted to post a quickie about it just to say the drama with the courier is over and I finally got it, and in one piece.