Cheap valves on RS anyone tried them yet?

[coopzone]

they have these:

RS Product Codes
678-4101 12AT7 ECC81 Double Triode, B9A base
678-4105 12AU7 ECC82 Double Triode, B9A base
678-4114 12AX7 ECC83 Double Triode, B9A base
678-4120 EL84 EL84 Output Pentode, B9A base
678-4108 6L6GC 6L6GC Beam Pentode, octal base
678-4117 EL34-B EL34 Output Pentode, octal base
678-4127 EL34-B-1 EL34 Output Pentode, octal base, matched pair set
678-4111 EL34-B EL34 Output Pentode, octal base, matched quad set
678-4123 KT88-98 KT88 Beam Tetrode, octal base
678-4136 KT88-98-1 KT88 Beam Tetrode, octal base, matched pair set
678-4139 KT88-98-2 KT88 Beam Tetrode, octal base, matched quad set

The EL84 costs £9.76 including vat and postage, thats better than most second hand ones! They appear to be china imports (one of the photos of the ECC85 shows the word china on the valve)

So anyone tried them yet?

Derek

[Refugee]

I have looked at them a few times but have not bought any yet..

[PsychMan]

Yes, I have bought and use very regularly 2 x EL84s from RS. They say "China EL84" on them. They run in my Bush SRG86 radiogram in single ended mode.

They sound undistinguishable to mullard ones to me. The radiogram is used nearly every day for many hours at a time, and has been for around 9 months now. It has a few times been on all night playing music.

No issues at all yet, the EL84s would get my seal of approval

I must add the SRG86 is a very good sounding radiogram, and is capable of pretty good fidelity

[Half a Mullard]

I seem to recall reading that some Chinese valves can draw more anode current? Although KT66's are not specifically mentioned I wonder if this could be an issue in something like a Quad II where transformers are run close to the limit? Just a thought.

[julie_m]

It's certainly worth bearing in mind. I would expect anyone changing the valves in a Quad II to check the anode currents as a matter of course, though -- and adjust the cathode resistor if necessary.

If I had just bought a pair of Quad IIs (a gal can dream, right?) then I would give them a thorough going-over with my trusty multimeter anyway, since I would have no idea what the previous owner might have done with them!

P.S. Was "ECC85" a typo, or is this possibly good news for owners of AM/FM sets?

[buggies]

I bought a couple of EL84s when rebuilding an MA12 (still to do its mate).
They provide the specified output in the amp and test to spec on Sussex tester - but have no yellow paint...

[cmjones01]

I bought one of these valves from RS a couple of years ago - it was a 12AX7/ECC83. It was a replacement for one in the power supply of a Tektronix 549 scope. It worked absolutely fine. No complaints from me.

Chris

[tri-comp]

Originally Posted by cmjones01

I bought one of these valves from RS a couple of years ago - it was a 12AX7/ECC83. It was a replacement for one in the power supply of a Tektronix 549 scope. It worked absolutely fine. No complaints from me.

Chris

And I bought the same and it lasted about 2 weeks in the pre-amp circuit of a guitar-amplifier.
Then the heater broke.
That's usually the very last thing to give in a valve so go figure.

/Torben

[kalee20]

Originally Posted by tri-comp

And I bought the same and it lasted about 2 weeks in the pre-amp circuit of a guitar-amplifier.
Then the heater broke.

Do they have the 'traditional' 90-day guarantee?

I'm sure RS would send a replacement.

[Scimitar]

Originally Posted by kalee20

Do they have the 'traditional' 90-day guarantee?

I'm sure RS would send a replacement.

When purchased as an individual, Consumer Regulations 2015 applies.

[M0FYA Andy]

It's certainly not fair to draw any conclusion on the basis of a single sample having failed after two weeks IMHO.

[tri-comp]

Originally Posted by M0FYA Andy

It's certainly not fair to draw any conclusion on the basis of a single sample having failed after two weeks IMHO.

I'm not drawing any conclusions on the basis of one sample failing.
I'm just saying that the picture isn't just rosy-red.
The valve was pulled from my stock to repair the amplifier.
It was delivered from RS more than a year ago so there's no hope of them replacing it for free.

[Scimitar]

Originally Posted by tri-comp

It was delivered from RS more than a year ago so there's no hope of them replacing it for free.

Unless you bought it in the course of business, you have six years in which to bring a claim for an inherent fault. Whether it is worth the bother or not is a different argument.

[MrBungle]

Yes they work. My Heath VTVM has one of the 12AU7's in it and has done for about a year now.

As for the returns from RS, they are really helpful and would replace that no questions asked. I have returned and replaced lots of stuff over the years with them and had no problems.

There is a "failure bell curve" for any device that is put on the market. Some people are unlucky enough to get the early failures. It happens.

[Herald1360]

Isn't the "bathtub" curve more applicable here- relatively high infant mortality followed by relatively long period of low failure rate then rising again for wear out?

Even if these valves are not up to the standard of historical Mullards or the like, they may still be "fit for purpose" to keep old equipment running within specs.

[vidjoman]

I've used several 6L6's in Jukebox amps and all have been to spec and lasted, some must be about 4 years older now. Have got some EL84's but have only subbed for a short time to check amplifiers working correctly.

[Refugee]

I have found RS to be pretty good on returns.
I had peltier chip fail during a drink cooler experiment and they replaced it for me without any fuss.

[MrBungle]

Originally Posted by Herald1360

Isn't the "bathtub" curve more applicable here- relatively high infant mortality followed by relatively long period of low failure rate then rising again for wear out?

Yes you are correct. I was half asleep when I wrote that clearly!

[PaulR]

Pity they don't do ECC807s !

[Andy Doz]

I've used RS's EL84 and ECC83 with no issues.