What are they made of and will paint adhere well? Those would be the two main questions I would have. If the outer part could be primed and painted then that looks like the only viable option. You'll never match the paint so go for something that gives a good contrast and doesn't look out of place.
Volvo paint 468, Lavasand Pearl, would be a reasonable match:
https://theaudiostandard.net/thread/833/quad-33-colour
I went to a local paint shop with the cover and they mixed a very good match, metal paint in a spray can.
I believe the knobs are a slight bit darker than the case, if i’m not too mistaken.
https://theaudiostandard.net/thread/833/quad-33-colour
I went to a local paint shop with the cover and they mixed a very good match, metal paint in a spray can.
I believe the knobs are a slight bit darker than the case, if i’m not too mistaken.
No. I found that dedicating one amp to the bass L + R and the other amp dedicated to the mids and treble L + R, is the golden ears combo -Did you go for two monoblocks?
Less distortion from the bass and low mids affecting the upper mids and treble.
Soundstage imaging would be the 'pay off' sort of, but since the treble and mids are driven separately...you get what I mean?
To answer your second question, see attachment:
Third Q. Yes, which also means you have half power. but i cant say crosstalk is a perceptible issue,
the one other thing in my mind was to separate the wiring loom to rid oneself of residual crosstalk, but I did't get round to that!
Attachments
Do you think my 4311's would benefit from monoblocks? My grandpa would be proud 😆
What is better than a 303? Two of them of course.
Now that I'm a little familiar with it I think I could buy one cheap to repair.
What is better than a 303? Two of them of course.
Now that I'm a little familiar with it I think I could buy one cheap to repair.
Great tip! In my monitor that looks like the darker tone of the knobsVolvo paint 468, Lavasand Pearl, would be a reasonable match:
Probably, but match impedances.Do you think my 4311's would benefit from monoblocks?
There are other aspects to that Quad Mono blocking attachment above and the 4Ω 16Ω loading.
Those JBLs are >4Ω
JBLs are 8ohms. Can it be done?
I always loved the idea of having monoblocks but never thought about doing it with the quad.
The downside is you can't use the 33 to power up two 303, maybe use it to trigger a relay.
I always loved the idea of having monoblocks but never thought about doing it with the quad.
The downside is you can't use the 33 to power up two 303, maybe use it to trigger a relay.
What do you mean by that?Probably, but match impedances.
Matching the Impedance of the loudspeakers, to the impedance of the outputs from the amplifier.
They should be the same/similar.
Essentially you are tying to match the loudspeaker and amplifier so that they are 'in tune' so to speak.
JBL's 8Ω, there were different version of that loudspeaker. Have you measured across the inputs pins with an Ohmmeter?
Is is around 4.6Ω? This wont give you the 'live' measurement but is will give you a rough idea.
The two methods in the Quad digram are a parallel 4Ω loading and a series 16Ω loading.
They should be the same/similar.
Essentially you are tying to match the loudspeaker and amplifier so that they are 'in tune' so to speak.
JBL's 8Ω, there were different version of that loudspeaker. Have you measured across the inputs pins with an Ohmmeter?
Is is around 4.6Ω? This wont give you the 'live' measurement but is will give you a rough idea.
The two methods in the Quad digram are a parallel 4Ω loading and a series 16Ω loading.
Exactly. The output impedance of a 303 is practically zero and doesn’t need matching to anything.
The statement applies to amplifiers with output transformers.
The statement applies to amplifiers with output transformers.
Yes, but he's asking about how it relates to the Quad Monoblocking attachment produced by Quad, in post 103.
OK. I can never see the point with 303s. They are already optimal into 16 ohms, and with MJ15003s you can double or even triple the current limiting diodes to get more into 4 ohms.
I measure 5.3ohm across.Have you measured across the inputs pins with an Ohmmeter?
If it can be done and I find a cheap one for repairs I might just do it.
Completely off topic:
With the system came also this mixer and equalizer. I don't want to introduce a bad link in the chain so I took some pics of the insides for you guys to take a look. An eq seems like a good thing to have, the mixer I could use as a way to get more inputs to the tape input of the quad. Bonus points for the Vu meters 😆
Don't know if the Phono1 and 2 are pre amplified or not. If not I could use this as a 4 way selector. The mic has to have a pre right?
It looks kinda cheap but the insides look decent.
You have nothing to lose having a play with the equaliser but its not really something I would want in that form. There were equalisers available from many big name manufacturers years ago. The mixer as a way to get more inputs isn't a great idea either I'm afraid. Having said that have a play and see what you think 🙂
I never liked that thing, I was curious to see if it made any sense/was well built. It is from a portuguese manufacture, very rare and umwanted 😆
What do you thing is the best way to get multiple inputs to the Quad?
I see some 4 to 1 rca selectors on amazon, they seem good. I thought it would just be a 4 way switch but they seem to have condensers and resistors in them 🤔
What do you thing is the best way to get multiple inputs to the Quad?
I see some 4 to 1 rca selectors on amazon, they seem good. I thought it would just be a 4 way switch but they seem to have condensers and resistors in them 🤔
I thought you had the 33 preamp, does that not give you enough inputs?
It would be normal practice to AC couple and also include high value resistors to terminate the caps to ground. Nothing wrong with that approach.I see some 4 to 1 rca selectors on amazon, they seem good. I thought it would just be a 4 way switch but they seem to have condensers and resistors in them
It is my only system so I'll be connecting everything to it.
For now I have R2R, PC and projector. I will add CD in the future.
Disk/Phono is for the Thorens and Radio1 for FM3. It leaves me Radio2 free but without mod it is only a 100mV input.
For now I have R2R, PC and projector. I will add CD in the future.
Disk/Phono is for the Thorens and Radio1 for FM3. It leaves me Radio2 free but without mod it is only a 100mV input.
Some loudspeaker manufacturers reduced the impedance to around 5.5Ω to make the speaker 'apparently' more efficient with a cheap 8Ω amplifier, this has the effect of premature amplifier clipping toward full power but easy going on the amplifier up to that premature clipping. It may be noticeable on transient peaks, as distortion.I measure 5.3ohm across.
The 303 outputs 45W into 8Ω with higher current 'dumping' that it's know for.
Live or dynamic impedance measurement is complex, involving phase relations and crossover complexity.
The general guide is to stay within +/- 20% of the impedance rating.
However, you could try your 303 with the 4Ω parallel bridging arrangement to test one speaker to see if it distorts early in the volume range, that way you would know if it's worth pursuing. It's important to have both amplifier modules functioning correctly throughout the power output range, matched components and matched bias on both modules. Run it loud for a few days if you can, then check the bias again to see if it's drifted, re calibrate the bias. Then do the above experiment.
Generally 8Ω systems sound better.
I don’t know what this means. The 303 isn’t known for current dumping, and the current at 45W into 8 ohms is defined by those numbers, not by the 303. And what is it higher than?The 303 outputs 45W into 8Ω with higher current 'dumping' that it's know for.
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