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jandl100
11-05-2010, 09:15
I'd like to try some valves with my low efficiency new speakers (83dB/W, 4 ohm).

So something(s) with a bit of sensible power on tap (50wpc minimum probably).

Up to £2k considered ... but happy to spend £5.79p. :eyebrows:

What Have You? :)

... or suggestions welcome.

Oh, and nothing humungously large, please!

StanleyB
11-05-2010, 09:19
I'd like to try some valves with my low efficiency new speakers (83dB/W, 4 ohm).
If we don't hear from you again after that experiment, it will answer my question on whether it would work or not :scratch:.

Stratmangler
11-05-2010, 10:27
Tough job - those MBL speakers are astonishing to listen to, but they really do need some grunt.

http://cgi.ebay.co.uk/AUDIO-RESEARCH-D70-MKII-VALVE-POWER-AMP-/110526932447?cmd=ViewItem&pt=UK_AudioTVElectronics_HomeAudioHiFi_Amplifiers&hash=item19bbeb25df - is this enough ?

DSJR
11-05-2010, 10:43
Audio Research is fine as long as you know a good service agent locally..............

What's the impedance of the MBL's? if it's 4 ohms I'd forget valves altogether and look for a decent high power ss amp - the Cambridge 840 power amp has good driving ability, no harshness apparently, costs what an amp of this ability should and should maintain good damping and control into a low impedance load, something valves just cannot do if they have output transformers (why 16 Ohm speakers were the norm back then). An amp with low damping/too high an output impedance driving low impedance speakers, has been shown to mess up crossover points..

If yu must have valves for this, I'd probably go with a trusted and reliable one like an EAR 509 pair, the Graff I think you mentioned doesn't have any valviness at all, except for the glowing bottles and hot running....

Stratmangler
11-05-2010, 10:49
What's the impedance of the MBL's?

First post in the thread Dave http://theartofsound.net/forum/showpost.php?p=122315&postcount=1

jandl100
11-05-2010, 11:11
What's the impedance of the MBL's? if it's 4 ohms I'd forget valves altogether and look for a decent high power ss amp

I have one already - an AVI Lab Series integrated. Really good.

I fancy trying valves. :)


If yu must have valves for this, I'd probably go with a trusted and reliable one like an EAR 509 pair,

I've had a pair of EAR 509/2 monos ... not the most exciting sound in the world,imo

the Graff I think you mentioned doesn't have any valviness at all, except for the glowing bottles and hot running....

Tee hee - we'll see if Dave is right. I've just succumbed and bought the Graaf 5050 :eyebrows: I should get it next week. The salesman guy at KJ West One said it would have no probs into 4 ohms. :ner: Of course I believe him!


Pretty, ain't it. :)

http://www.graaf.it/5050eng.htm

Rumours are around that Graaf has died, but according to the KJ guy they have been bought out by Audio Analogue.

DSJR
11-05-2010, 11:22
The Graff has output trannies and this automatically means a high output impedance!!!!

The KJ guy (Arif, Richard or the other one?) wouldn't perhaps even know as long as he gets your dosh..... ;)

Of course a valve amp will drive a 4 Ohm load. It's what it does to the speaker while it's doing it that matters..

By the way, AVI stopped making separates largely because of the likes of the current Cambridge amps, which are at least as good in design and far cheaper to buy because of the Chinese manufacture. AVI used Allner-Hamblin (my generation) and now LS-Designs (current electronic production) in the UK for their circuit assemblies.

jandl100
11-05-2010, 11:29
Actually, it's Graaf, not Graff ... see! - ya don't know everything! :eyebrows:

Ali Tait
11-05-2010, 11:31
Plenty valve amps around with 4 ohm taps on the output trannies..

Jerry,how about KEL80? A WAD design with parallel push pull EL34's I think it was-80w per channel.I'm sure someone on the WD forum was selling one recently.Might be worth a post there.

Spence
11-05-2010, 11:33
Pretty, ain't it. :)

http://www.graaf.it/5050eng.htm


Very nice ..

jandl100
11-05-2010, 11:35
Plenty valve amps around with 4 ohm taps on the output trannies..

Jerry,how about KEL80? A WAD design with parallel push pull EL34's I think it was-80w per channel.I'm sure someone on the WD forum was selling one recently.Might be worth a post there.

Hi Ali, EL34 choobs? Hmmm ... I'm not a fan. I've yet to hear an EL34 amp that can maintain my interest.

We'll see how I get on with the Graaf's KT88's. :)

Ali Tait
11-05-2010, 12:00
I think it was,I'm not certain.

Tarzan
11-05-2010, 13:59
Prima Luna Dialogue Two , 38w but supposed to be a little powerhouse Jerry.

jandl100
11-05-2010, 14:43
Thanks Andy - but the Graaf 5050 is on order now. :)

I've heard a couple of Prima Luna stereo integrateds at a friend's place and a pair of PL monoblocks at home ... I was unimpressed really. No pizzaz or joi de vivre to my humble ears.

John
11-05-2010, 14:57
You should enjoy the Graaf Hope it works out

Spectral Morn
11-05-2010, 17:41
These run very hot and need a lot of ventilation. We had problems with one particular graaf amplifier that kept blowing power supply caps (output transformerless)

I would suggest Bat a VK 60 or 75 but they are physically big, very big and you need to run them balanced for the best sound.

MBL use solid state amplification and that is the only way I have ever heard them run. However valves would bring something very interesting to the MBL speaker party, very interesting. I for one am very keen to read how Jerry gets on as MBL speakers (the ones I have heard) did impress me, though it was a full MBL system on dem; which makes it hard to say what was doing what.........


Regards D S D L

Jonboy
11-05-2010, 18:55
Hi Jerry,

You could come and borrow my Beard kt88 p100 for a play if you want, it worked quite well with esl 63's

It weights around 30 kg so quite a lump

The offer is there but i will not post it

Themis
12-05-2010, 19:30
Pretty, ain't it. :)

http://www.graaf.it/5050eng.htm

Rumours are around that Graaf has died, but according to the KJ guy they have been bought out by Audio Analogue.
A real beauty, Jerry, congrats. :)