Quad 303 any good?
- Thread starter bourney
- Start date
Hmn . . .keep that Quad. I bought one from a pal who'd just had it recapped in Britain. It is driven by a Croft Vita and although it's now 40 years old I wouldn't part with it for love nor money. You can change the way it sounds by rolling tubes for the pre-amp - 6SL7GTs made a big difference for me. Enjoy . . .
Bokway
Bokway
DSJR
Between us and them
A bad 33 is a dog, but a good one can sound enchantimg in its carefully band-limited kind of way..
IIRC, the 34 inverts the phase and in some systems this can be disastrous. I also found it a bit "limp wristed" on driving rock or post-punk stuff. They wear out their supply caps too and leaky ones can damage the mother-board if left unattended. Love the FM4 though and while FM is still alive, they make great general purpose tuners.
IIRC, the 34 inverts the phase and in some systems this can be disastrous. I also found it a bit "limp wristed" on driving rock or post-punk stuff. They wear out their supply caps too and leaky ones can damage the mother-board if left unattended. Love the FM4 though and while FM is still alive, they make great general purpose tuners.
Hi guys.
The Quad 33 control unit (notice I didnt call it a pre-amp
) was in production for over a decade. The early ones will sound a bit muted and dull if they have not been refurbished but I have a late 70s unit that sounds quite good. Also if you want to use it to its fullest potential you may was to get all the electrolytic caps replaced as these will have dried out and will be in need of replacement.
LPSPinner.
Radfordman
pfm Member
As many have said, a well serviced but standard 303 is a very good sounding amp. I agree in making one change, increasing the output capacitors in value (standard 2000 or 2200 uF) to about double that figure or even to 10000uF. This is especially effective if low impedance speakers are used. This will probably help the bass on some speakers
I have four 303's, all of them sound better than my Quad 405-2 with Burr Brown op amps.
However, I think I still prefer the sound of my Quad II's
And the best amp I have is the Radford STA25 III
If only I could find a solid state amp with the quality of sound of the STA25. It may be possible, but probably not with anything that I can afford.
I have four 303's, all of them sound better than my Quad 405-2 with Burr Brown op amps.
However, I think I still prefer the sound of my Quad II's
And the best amp I have is the Radford STA25 III
If only I could find a solid state amp with the quality of sound of the STA25. It may be possible, but probably not with anything that I can afford.
DSJR
Between us and them
A CB NAP160 sounded at least as good as a ten year old STA25 as I replaced my Radford with one back in 1980 or 81, the Radford re-locating to Budapest.. I suspect a Cambridge 840 series power amp would eat both of them and for not that much money. The Quad 909 is good too IMO, having power and grace aplenty.
Radfordman
pfm Member
Well, when we were making and selling high quality speaker systems, our preferred demonstration amplifier was the Radford STA25 III, our customers always rated it. I have not tried many Naim amplifiers, but some of our customers returned their amplifiers to Naim for unacceptably poor sound quality and bought Quad, and were happy. We designed and built the speakers for the home of the Sales Director of Audax UK, his amplification was Quad.
I am not familiar with newer amplifiers, but will certainly look into the Cambridge 840.
Robert
Tapehead
Many moons ago I visited a friend who said he'd just picked up a pair of power amps dirt cheap to try with his Epos ES14s.
Turned out they were a mint pair of Radford MA15s.
Back in those days I thought that valves were the work of the devil, so passed up the opportunity to buy them for about £200 - stupid me!
They did sound excellent, if underpowered for ES14s.
Turned out they were a mint pair of Radford MA15s.
Back in those days I thought that valves were the work of the devil, so passed up the opportunity to buy them for about £200 - stupid me!
They did sound excellent, if underpowered for ES14s.
Radfordman
pfm Member
MA15 22 Watts RMS and STA15 22 Watts RMS per channel, so more power that one might expect from the model numbers.
Pair of MA15's dirt cheap, lucky friend.
Robert
Tapehead
Still a bit light for ES14s, they really need something fairly potent and with plenty of grip.
How do you find the Quad II compares to your Radford when the former isn't being stressed?
Radfordman
pfm Member
Both are very good, difficult to do a proper A/B so a little difficult to say. It would also depend a lot on which speakers are used. The Quad II is euphoric and flowing. Not to say that the Radford isn't. Oh I hate trying to describe sound quality.
The dynamics of the Radford may be greater, we are talking of small differences though.
I am happier with these two amps though, more than most other amps and can listen for hours using these without listening fatigue.
Back to the 303, this amp works particularly well with Quad ESL57's, well one might expect this.
The dynamics of the Radford may be greater, we are talking of small differences though.
I am happier with these two amps though, more than most other amps and can listen for hours using these without listening fatigue.
Back to the 303, this amp works particularly well with Quad ESL57's, well one might expect this.
DSJR
Between us and them
I would dearly love to hear an STA25 again, one which was in fully fettled condition (mine was in need of a service to caps etc). There's nothing hugely wrong with the basic circuit Naim uses (Avondale seem to have shown this) but they did seem to need careful setup when new and almost certainly another tweaking after a few months of good use, otherwise they sounded hard toned. As the years have gone on, Naim seem to have improved their output devices and the current range is different again and, it seems, far more stable.
The Quad II's, whether original, or Croft re-built like mine (sacrilege to some) do have a wonderfully coloured euphony to them. into speakers like ES14's, one could suspend (musical) disbelief with ease and come away from the music session with a huge grin..
I've curently got so many odds and ends around and about I cannot justify a Quad 33/303, but I do remember good, well looked after ones sounding very good, as long as the speakers didn't need huge damping factor and you used music led by the midrange (not drum-n-bass or techno...
)
Radfordman
pfm Member
I would dearly love to hear an STA25 again, one which was in fully fettled condition (mine was in need of a service to caps etc). There's nothing hugely wrong with the basic circuit Naim uses (Avondale seem to have shown this) but they did seem to need careful setup when new and almost certainly another tweaking after a few months of good use, otherwise they sounded hard toned. As the years have gone on, Naim seem to have improved their output devices and the current range is different again and, it seems, far more stable.
The Quad II's, whether original, or Croft re-built like mine (sacrilege to some) do have a wonderfully coloured euphony to them. into speakers like ES14's, one could suspend (musical) disbelief with ease and come away from the music session with a huge grin..
I've curently got so many odds and ends around and about I cannot justify a Quad 33/303, but I do remember good, well looked after ones sounding very good, as long as the speakers didn't need huge damping factor and you used music led by the midrange (not drum-n-bass or techno...
The Naims that I was referring to were many years ago. I was lucky with my Radford STA25 II, I got it second hand and it was like new. I visually check the electrolytic capacitors (occasionally) and they seem fine. I guess that they have lasted so long due to the good ventilation in the amp and that it is not in a cabinet.
I suppose that most would say replace the electrolytics, I know the consequences of the more critical ones failing.
My Quad IIs are completely original apart from replacing the dual PS smoothing capacitor with an identical type in one amp. Not sure that I would call the sound of a Quad II as coloured, but I agree with the term euphony .
I agree with your statement about the Quad 303 and speakers that didnt need a huge damping factor but when I replaced the 2200uF output capacitors with 10000 uF, there was a big difference in the way it controlled the bass of some speakers. I was not expecting such an improvement. Through Quad ESL57s or 15 Ohm Tannoy DCs, I would not expect any real change.
Just picked up on this... it seems that the 33 and 44 preamps and 303 and 405 power amps are inverting.
Tried it this evening in my setup (303 with passive pre) and it has made a huge difference. I have dipole radiating speakers (small Magneplanars) and the difference is probably not as significant with enclosed speakers.
Perceived difference is cleaner, smoother mids and treble.
Tried it this evening in my setup (303 with passive pre) and it has made a huge difference. I have dipole radiating speakers (small Magneplanars) and the difference is probably not as significant with enclosed speakers.
Perceived difference is cleaner, smoother mids and treble.
Yeah, had Andy831 round last week. The 34/405.2 sounded broken, so flipped the speaker cables round & well, you know how much batter it sounds IN phase
.Then fed the SB directly to judge the effect of the Pre (which was shown to be a bit dull) & had to switch them right back.
Then tried both 303s & found them to be the same.