Lampizator Big 7

[wisnon]

Yes, accept no (Psvane) substitute! LoL
They are pretty robust too and will last longer than the Psvane average. Not bad looking either, but cant compare to the "supermodel" EML mesh 300b for drop dead goargeous looks!...but then what can?

I have no problems with the 300b sound, except the slow/mechanical ones.

 

[bonzo75]

I wouldn't spend money on any 300b except possibly the RK which I haven't heard properly and too because they were a special voiced valve for Lampi

 

[wisnon]

I have all those mentioned 300bs Ked...
Lukasz is the one who put me on to the UK Design 300b some 3 years ago!

 

[Wookii]

OK, so yesterday I acquired a second hand set of KR 242's. Put them in my B7, waited half an hour for warm up, and then started playing some music. It was instantly obvious that they reveal more detail and have a more palpable 3D effect than the 101D's but . . . on some tracks (seemingly those high with higher peak output) louder higher frequency sounds were distorting quite badly.

I have read throughout the various Lampi threads that the 242's output is an issue, and can overdrive the input on a pre-amp - is this what might be happening here? I did have to reduce the preamp volume from about 38 to 30 (max is 80), but that volume was otherwise fine at that level.

The input overload limit on the ML 585 I was using is 5.5v (44k Ohm input impedance). Is it likely that the 242's in the B7 (which has a 600mV output with KR 45's installed as per the Lampi measured spec sheet) is over-driving the input on the 585, or could there be an issue with the tubes? If it was an issue with the tubes would they distort on all tracks, rather than just the dynamic peaks of certain tracks?

Once I secure a new power amp, I can revert back to my ML 326S, which has a max input of 13.2V (100k ohm input impedance), which should give more headroom for the 242's, if that is the issue.

I do have some 20dB inline XLR attenuators - not something I would want permanently in the signal path, but would they allow me to reduce the signal from the B7 into the 585 to see if it eliminates the distortion?

Another option is to engaging headroom management in Roon to reduce the input level of the tracks going into the DAC - or is this unlikely to affect the output from the B7 into the 585?

Any thoughts from technically minded folks who can calculate such things? Is there a way for an end user to test the output voltage of the B7 with various tubes installed?

 

[Alrainbow]

To test the output on your dac is not that hard
You would need a test cd that has simple freq sounds. 1khtz is good.
A digital DVM and a means to access the conductor of the output line
Set the meter to AC
You would then attach one lead to the Chasse or Shield of interconnect and the other to the center pin.
Measure both with the preamp connected and without.
As for the 242 tubes. I own them and two lampi dacs.
My big 7 has a lower output and loves the tubes
My head dac has a higher output and does not
Neither of the dacs distaorts like yours do. But the virtues of the 242 are not as previlent as on the B7. The tak is a great recti as well and Miles ahead of the eml recti.
Finding a way to make the 242 tubes sound great is a worthwhile venture.
Another great tube is the we275 it is like a baby 2A3. I use them and the eml mesh 2A3 in my head dac and a cheap CHINESE 274B soujds best with them.
Lampi dacs are extremly well adaptable for any system if one reads and tries tubes.
I also have on loan a pacific dac too that is also
A very versitle dac with tube rolling to.
Feel free to post I am others will reply to help.

 

[Zero000]

It will be overloading the preamp. There's no way earlier standard B7s were ever designed to take 242. The same thing happened when I tried Keds in mine.

If you want to use it, you'll have to send it back to Lampizator for a modification.

Personally I wouldn't bother. There are plenty of other great valves out there for it not to be worth the effort. Ked won't agree, but hey.

My own advice is to ignore anything anyone says about any valve (well, almost - it is impossible not to be influenced), and try some older NOS triodes as well as some of the more recent manufacturers. Each will change the sound in their own way, and that change simply isn't related to their cost. It is a voyage of personal discovery for you, and you definitely should not follow the advice of anyone. The best valve in one system won't be the best valve in another, and factoring in personal preference on top of that means there is no best valve.

 

[Wookii]

To test the output on your dac is not that hard
You would need a test cd that has simple freq sounds. 1khtz is good.
A digital DVM and a means to access the conductor of the output line
Set the meter to AC
You would then attach one lead to the Chasse or Shield of interconnect and the other to the center pin.
Measure both with the preamp connected and without.
As for the 242 tubes. I own them and two lampi dacs.
My big 7 has a lower output and loves the tubes
My head dac has a higher output and does not
Neither of the dacs distaorts like yours do. But the virtues of the 242 are not as previlent as on the B7. The tak is a great recti as well and Miles ahead of the eml recti.
Finding a way to make the 242 tubes sound great is a worthwhile venture.
Another great tube is the we275 it is like a baby 2A3. I use them and the eml mesh 2A3 in my head dac and a cheap CHINESE 274B soujds best with them.
Lampi dacs are extremly well adaptable for any system if one reads and tries tubes.
I also have on loan a pacific dac too that is also
A very versitle dac with tube rolling to.
Feel free to post I am others will reply to help.

Thanks for the reply Al. I have a DVM, but the connection is balanced - so on a balanced cable where do I put the meter probes? Red to pin 2 (hot) and black to shield (ground)?

 

[Alrainbow]

Why would you post in absolution when there are so many variables in ones system and even the dacs. I am proof that your post is wrong mine is a late 2016 B7 with the plastic top.
Don’t inform people to conclusions that are not true I all cases it’s rude. Also how many tubes have you tried ? I won’t tell you how many own but lampi is about tube rolling to get the perfect sound for each of us.
Kedar has boasted of the 242 and until I heard them played well twice now they are a tube to chase. The aquired fruit well amazing.

 

[Alrainbow]

No shield is used in bal use both pins inside not the shielded one.
This yields the signal alone. Is your B7 bal ?

 

[Zero000]

Thanks for the reply Al. I have a DVM, but the connection is balanced - so on a balanced cable where do I put the meter probes? Red to pin 2 (hot) and black to shield (ground)?

The test signal will be meaningless unless you know what level it was recorded or synthetically generated at. You want something that corresponds to full amplitude output throughout the entire test.

 

[Alrainbow]

https://www.google.com/search?clien...30j0i22i30./3K52T3bTfk=#imgrc=YsbOP2wsZbqkbM:

 

[Wookii]

It will be overloading the preamp. There's no way earlier standard B7s were ever designed to take 242. The same thing happened when I tried Keds in mine.

If you want to use it, you'll have to send it back to Lampizator for a modification.

Personally I wouldn't bother. There are plenty of other great valves out there for it not to be worth the effort. Ked won't agree, but hey.

My own advice is to ignore anything anyone says about any valve (well, almost - it is impossible not to be influenced), and try some older NOS triodes as well as some of the more recent manufacturers. Each will change the sound in their own way, and that change simply isn't related to their cost. It is a voyage of personal discovery for you, and you definitely should not follow the advice of anyone. The best valve in one system won't be the best valve in another, and factoring in personal preference on top of that means there is no best valve.

Thanks for the reply. When you say 'earlier standard B7's', mine is not the older point-to-point wired version, but the newer PCB version (if that is a defining difference) - the tube toggle switch on the rear certainly has a "45/242" setting labelled on it.

I'm keen to get the 242 working if I can, as it has such high praise bestowed on it. If I then exclude it as my own personal preference/voyage of discovery, as least I will know I tried it. Certainly on the few tracks that did play without any distortion, they did sound excellent.

 

[Alrainbow]

It’s not meaning less of it’s distorted it shows the output is too hot of course this is not an accurate method in design

 

[Alrainbow]

Let me find out what is the best means to fix your output voltage issue. Need a few hours to post back. But those tubes are well worth chasing
Magical when they are playing well.
Mine is a PTP not Board. It’s also been revised a few times at Poland

 

[Zero000]

Thanks for the reply. When you say 'earlier standard B7's', mine is not the older point-to-point wired version, but the newer PCB version (if that is a defining difference) - the tube toggle switch on the rear certainly has a "45/242" setting labelled on it.

Yup that's different. Obviously the output should be OK as it has been designed to use the 242. Definitely try and do the voltage check.

 

[Alrainbow]

NORMAN said the same thing when I told him
How great the tubes souded.
Here is a little tidbit the new pacific plays them at levels I never heard before the tube is truly an amazing sound scape

 

[microstrip]

(...) My own advice is to ignore anything anyone says about any valve (well, almost - it is impossible not to be influenced), and try some older NOS triodes as well as some of the more recent manufacturers. Each will change the sound in their own way, and that change simply isn't related to their cost. It is a voyage of personal discovery for you, and you definitely should not follow the advice of anyone. The best valve in one system won't be the best valve in another, and factoring in personal preference on top of that means there is no best valve.

Wise words. But many audiophiles love absolute rankings ...

 

[Alrainbow]

Worlds that have some truth and some misconceptions too.
Each tube has a base sound and it’s sound will not change drastically. Example a 101d is thin but has air a gteat tube for classical or live. Bad for rock or poor recordings.
As for system synergy this is the isllusive sound we all chase and All matters

 

[microstrip]

(...) Example a 101d is thin but has air a gteat tube for classical or live. Bad for rock or poor recordings.
As for system synergy this is the isllusive sound we all chase and All matters

I think you are indirectly agreeing with User211 - IMHO dependency on system can be much stronger than on the recording type. BTW, I can not understand how a "thin" sounding tube can be adequate for classical.

 

[Zero000]

Worlds that have some truth and some misconceptions too.
Each tube has a base sound and it’s sound will not change drastically. Example a 101d is thin but has air a gteat tube for classical or live. Bad for rock or poor recordings.
As for system synergy this is the isllusive sound we all chase and All matters

Well they are measurably different using a test mic on your speakers - I've done that test. But the variations in FR are relatively small compared to the in room difference of say using the same speakers in different rooms.

Plus Lampis have changed a lot in spec over the years so one DAC naturally doesn't sound quite the same as another, as you know.

Actually I would agree that if all Lampi owners had the same spec Lampis, and all where given say 10 different triodes and 10 different rectis to try, a pattern of preference would emerge, as some valves really are relatively poor.

But basically the gist of what I said does have more than a measure of truth to it, so I'll stick by it to a fair extent.

Personally I find my preference alters almost on a daily basis depending on what I am listening to and what sort of mood I am in.