Amp upgrade with Canton speakers: Feasibility study

[Asit]

That's an interesting suggestion, arj. Thanks. I may try that out, but may be , after a few days. However, I have not understood the working principle. The nominal impedance of my speakers is 4 Ohms, and the tap at the amp is set at 4 Ohms too. Setting the tap at 6 Ohms will only increase the demand on the amp. Isn't that true?

Regards.

 

[arj]

That's an interesting suggestion, arj. Thanks. I may try that out, but may be , after a few days. However, I have not understood the working principle. The nominal impedance of my speakers is 4 Ohms, and the tap at the amp is set at 4 Ohms too. Setting the tap at 6 Ohms will only increase the demand on the amp. Isn't that true?

Regards.

Oops..mine were 8 ohms and so the 6 ohms works..yours will not. the bass may only go worse. sorry..should have checked.

 

[Rajiv]

Hi,

Oops..mine were 8 ohms and so the 6 ohms works..yours will not.

Arj,have you tried the 4 ohm tap with your speakers?

Regards
Rajiv

 

[arj]

rajiv i did that..the change from 6-4 was not something i could make out as a difference

 

[Asit]

Here is a quick update on the new power tubes.

When I wrote the last post,the tubes had about 3 hours on them. Now they have about 8 hours, and they are now really beautiful sonically.

A few points:

1. The whole presentation is really smooth, no rough edges in any frequency regime. At the same time, the sound is really open, and very natural, much more than the previous Sovtek tubes. I have especially tested with a CD which I am very familiar with (I was present in the studio when this recording was made with old Studer equipments, the mastering was done wrong the first time, and then it was corrected).

2. I do not think I can complain any more about the bass. It has become very musical and well paced.

3. There is an air around each sound which is quite remarkable.

4.The top has now opened up. I do not know how to describe it in words, but it has become better controlled, yet with openness and smoothness.

5. The dynamics is incredible.

6. Could it be that these tubes have bigger gains? Because I am now playing my amp at lower volume levels.

In short, very happy with these tubes. They work marvelously in my system. If my recommendations count for anything, I strongly recommend them to whoever looking for EL 84 tubes (especially the performance to price ratio is very very high).

Yet to try the Telefunkens. Do not know what they will do to the sonics. Should I try them now? Or wait a little longer?

Regards.

 

[Rajiv]

Hi,


Asit,have you tried the BEL EL84 tubes?


The Telefunken 12AX7/ECC83 tubes will have 30% higher gain than the 5751 tubes.

Regards
Rajiv

 

[Asit]

Rajiv,

I have not yet tried the BEL tubes. I first wanted to try out a set of closely matched tubes. Even though, as Sridhar pointed out, the Leben has auto-baising and therefore do not need matched tubes, I would think, the auto-biasing must have some limits, by that I mean there has to be some limits beyond which the amp will not be able to adjust the bias. Please correct me if I am wrong. Since you said, the BEL tubes that you sent me a long time ago are matched to about 10%, I need to find out if the amp will work perfectly upto 10% imbalance. Consider me a novice in this business, and I am usually very very careful when handling or changing anything with my audio gear. But this approach has stood me in good stead as you know that I still have many of my 3 decade old stuff perfectly functioning. Still now whenever I put in a new CD or vinyl, I start from zero volume setting.

In my previous post, when I said, the gain seems to be more, I was talking about the power tubes alone (since I am yet to try out the Telefunken 12AX7 pre tubes). Does it make sense to you that these power tubes may have more gain? But they really appear to be that way. Or, is it because, these are really quiet tubes, and hence they have better signal to noise ratio and therefore I can listen to music with these tubes at a lower volume setting?

I'd also like to have the opinion of experts like you on this issue of the tubes settling in after a few hours. Since my knowledge of tubes is very limited, at present I have no clue on this subject - I have just described whatever I am listening. I hope my observations are not too subjective. But I am sure, the bass was a bit loose in the beginning. But I suppose I also need to keep in mind that the first time when I listened to these new tubes, the amp was warmed up to a max of 5 minutes, because I could not wait any longer to hear the effect of changing the tubes.

Regards.

 

[arj]

Asit my amp takes at least 15 to 20 min for warmup...


Sent from my iPad using Tapatalk

 

[Asit]

Hi all,

Last evening I could not wait any longer, and finally replaced the stock pre tubes (GE 5-star 5751) by the newly acquired matched pair of NOS Telefunken 12AX7 ribbed plates. For those who may not know, 5751 and 12AX7 are fully compatible tubes, the 5751 has about 70% of the gain of 12AX7.

The very first impression? - Aweful!!! The sound was really harsh for the first 10 - 20 minutes. I thought what an waste of a lot of my hard earned money (because they are really expensive). Either, the Telefunkens do not fit well in the Leben circuit (indeed there is no report on the net of TFK 12AX7 being used in Leben CS 300 family), or all the rave reports I read on these tubes were not true, or my ears are not at all good.

However, gradually in a quick span of time (in an hour I'd say), the tubes started singing. And sing they did - I kept on listening till 1:30 AM, and again this morning for about a couple of hours before coming to office a bit later than normal.

Impression on them now in a couple of words : Precise and beautiful - everything is right about them. Worth every penny I spent - and I am so happy I did. They easily beat my stock tubes (GE 5 star 5751 and BTW they were no slouch either, the GE 5751s are among the most respected tubes of their kind).
In the process, I am again rediscovering my speakers - they can sound this good!

My heart is revolting against dissecting the music, so I will not go into much details; but let me just give a few points which I find interesting. For example, the presentation is not as forward as the 5751s, they are actually a bit more laid back and relaxed, but this happens without hurting the pace of the music, actually enhancing it. Imaging and staging is perfect and more 3D than in the 5751s. Tonality is just right. In the middle of a soprano-like female vocals, if there is a deep bass needed, they produce it perfectly. I can go on and on, but words are only limited.

When I lived in Germany (1988-92), there was a place I knew where one could get Telefunken tubes for approx 1 Deutche Mark each. At that time I did not care much about tubes, but I should have.

One message for all Leben CS 300, CS 300 XS and CS 300 X owners: you can surely consider the Reflektor 6P14P-EB (or EV) and Telefunken 12AX7 tubes in combination for these amps (there are no reports of this combo being used in the Leben CS 300 family, as far as I know). If you want confirmation, please come down to Kolkata to have a listen.

Regards.

 

[Dr.Bass]

This is interesting Asit !! Nice to see that all these tube experiments have worked in the right direction. Just to give you an heads up, I used to have a pair of Raytheon 5751, Black plate with Windmill getter. This I was using with my Acoustic portrait preamp. Here in Singapore I no more saw a need for it so decided to sell it. It is an expensive tube btw. The buyer happened to be a Leben 300 owner and interestingly he was using a Telefunken 12AX7 tube. After putting in the Raytheon 5751 he was so happy that he sent me 5 SMSes in the same evening only writing about how beautiful his amp is sounding and how big an upgrade it is over the Telefunken . I have not heard his system but just to give you an idea, if you happen to find a Raytheon with Windmill getter, please dont miss it. They have super long life btw.

 

[Asit]

Dr. Bass,

Thanks for your encouragement. The Raytheon 5751s are good and many use them (and RCA 5751s as well) as driver tubes (in the pre section) in these Leben CS 300 family amps with very good results.

Two comments about the Telefunken tubes. To start with, a general comment. There are many many fake Telefunken tubes around, all potential buyers should be careful. All genuine Telefunken tubes have a diamond mark engraved at the bottom of the tube (encircled by the connector pins). Some people on the net say that the ribbed plates do not have the diamond mark, but that is not true, all TFKs have it (I have ribbed plates and they have the diamond marks). The other signature of a genuine TFK tube is that the name label on the glass is almost erasable, and so many genuine TFK tubes will not have a proper name label. With a bit of rubbing one can easily get the label off. The chinese fakes have very firm labeling that does not wear out easily. Many genuine TFK tubes also have other OEM labels, but one easy way to identify them as TFK is to look for the diamond mark at the bottom. I am not sure if the guy you sold your Raytheon 5751 to had a genuine TFK, because the fake ones are reportedly very bad.

The other comment is about system matching in general (including cables) and tube matching between the pre and the power section. For example, with a very neutral amp and other components (as neutral as possible), if one has TFK both in the power and the pre section, the sound may be thin, quite bright and generally not very bearable. The signature of the TFK tubes (especially the 12AX7) is very accurate sound with almost infinite amount of details. Since the Leben is a reasonably accurate amp itself, I had to keep in mind the signatures of the rest of my system and also to work extra hard to ensure a proper match for the power tubes. This is also the reason (besides them being cheaper) I chose ribbed plates instead of the smooth plates - the ribbed plates are equal to the smooth plates except that the mid and especially the lower mid is warmer than smooth plates and they have a fuller bodied sound. The output tubes I chose have warm mids and a wonderful airy top, but perhaps gives up a tiny bit in the bass precision (as I said their sound signature is NOS Mullard-like), but they also have wonderful resolution (which perhaps is not the forte of the NOS Mullards). However, the bass gets very tight contribution from the TFK pre tubes, and hence the end result is nice, at least in my estimation. I have no idea what the other tubes or the rest of the chain was, for the Singapore guy to whom you sold your 5751 and hence cannot say anything on why he did not like the TFK in his system.

You should certainly visit my place next time you are in India, because when you came last time, there were many imperfections in my system (The CDP had problems, so did the amp with the volume pot).

Regards.

Note added later: Forgot to add one more thing about fake TFKs. Some of the Chinese fakes have golden pins. As far as I know TFK never made any tube with gold pins, not even with their highest grade tubes for medical use.

 

[Entry_Level]

Hi Asit,
I'm a Canton owner. I posess a pair of entry Level floorstanding speaker from this manufacturer (le 207). Lately, i was thinking of upgrade speakerwise. My research on the web brought me here. For the passed two weeks, i've read all 54 pages of this thread. I've been looking into products mentioned, concepts suggested, reviews and experiments involved. This should be sent to a publisher as a guide.

Also, as you are a proud owner of Canton Karat, i was wondering if you still have them? First, because all Karat owners, i've met, had upgraded everything but the Karat. All owned different models from also different eras. Secondly, because maybe this might be one of my choices as an upgrade.

My setup goes as follow:
Arcam A65 +
Arcam DV78
Canton Le207
Tributaries interconnect
AudioQuest speaker cables

Cordialement

 

[Asit]

Hi Asit,
I'm a Canton owner. I posess a pair of entry Level floorstanding speaker from this manufacturer (le 207). Lately, i was thinking of upgrade speakerwise. My research on the web brought me here. For the passed two weeks, i've read all 54 pages of this thread. I've been looking into products mentioned, concepts suggested, reviews and experiments involved. This should be sent to a publisher as a guide.

Also, as you are a proud owner of Canton Karat, i was wondering if you still have them? First, because all Karat owners, i've met, had upgraded everything but the Karat. All owned different models from also different eras. Secondly, because maybe this might be one of my choices as an upgrade.

My setup goes as follow:
Arcam A65 +
Arcam DV78
Canton Le207
Tributaries interconnect
AudioQuest speaker cables

Cordialement

I am really sorry to be very late in replying. As you can see, I am not very active in forum these days. Just busy with work, or busy listening to music, or both. Ha ha.

Thanks for your appreciation of the thread. I agree, it has accumulated a lot of wisdom and experience at one place, all this is due to the generous contribution of the forum members to whom I am forever grateful.

You have a good amplifier in Arcam A65. I have heard this amp a few times, and I have liked it. In fact I have liked nearly all Arcams I have heard so far. This is a brand I respect. The biggest virtue of the amp is that it is simple and clean. It does not try to do a lot of things, it does the basics well. That means, it gives you a clean uncluttered sound with good tonality. Now, you need to keep all these qualities when you choose speakers for this amp. Hence it needs to be a clean speaker (that is, low noise floor), open sounding, tonally neutral and an easy load so that the little amp (with its power rating) can drive it effortlessly. Easy load does not necessarily mean high sensitivity, one needs to look at the impedance versus frequency plots. The impedance should not drop to low values for a reasonable frequency range, preferably above 40 Hz or so. High sensitivity always helps.

You have not mentioned your budget and musical preference. Hence the choice is very open.

I still have the Karat 60s. They are now almost 25 years old and still performing flawlessly. I wish they last as long as I live.

I have no idea about the current Canton speakers, or Karat series. I guess they may not have a Karat line of speakers any more. They have a Vento series, I believe, comparable to the present-day Karats. And then they have the reference line speakers which have been praised very highly by a lot of people, including Stereophile magazine. I suppose my Karat 60 speakers are something equivalent to some of these current reference line speakers. My Karat 60 as well as the current Reference series are hand-crafted with all drivers and crossovers made by Canton themselves.

Regards

 

[Entry_Level]

Hi Asit,

Thank you very much for your answer, also sorry that i've reply Late my self too. Gratefull too that all those members indeed had participante to such a great body of work.

To answer your questions, firstly my taste on the music matter goes from acoustical folk, western classical, all periods of jazz, electronica and even metal...just to give you a general picture. Budgetwise...well i have a tendency to shop around a lot. So i very often turn to used market. I made huge savings going this way. In the course of my reading, i've checked almost every product mentionned (depending on the giving review ). Checked : reviews, retail value and used market value...was very enjoyable!

My understanding of your post is : since my amp is a low power integrated amp i should not look for speakers which have a frenquency response lower than 40 Hz. Also, something around the 90ish dB, otherwise my little guy (A65) will have a hard time pumping the demand. The le207 are 40hz - 20khz with 86 dB. Maybe i should first look into a power amp first? So this might open up my options. Since Dynaar made some interesting experience on that path. The only thing, which i part with Dynaar concerning his experience, is that i'm not sure about Monitor Audio find them not as pleasant in the hi-freq., as the Canton are. Back when i bought the Cantons, the Karat were still in the lineup. The Vento were the flagship series and back then they were selling from nearly 5k to 25k CAD. Never seen Vento on the used Market. Now concerning the Reference series, it seems like a fairly new line. Based on my experience with Canton users, i won't those used anytime soon!!!!!

As you said, my setup has a clean sound, actually a very clean one. When i listen to it, i strongly feel it could generate a larger stage. Also, somehow i feel it could produce a lower bass...with a little more muscle! So that is why : i'm here writing to you.

Thanks again for your input on this.

Regards