which tubes for Demeter vtbp-201s?

BiigM · #1 09-02-2010, 05:47 AM

Hi guys.

I just put my vtbp-201s in a rack with a Crest CA9. First up I have to say that it sounds awesome. And definately something else than my aggie db750.

I like the bass and mid area, but the treble is a little too much. I usually turn the treble down to 9 o'clock and even cut a little tone on my bass sometimes depending on style. presence and bright switch are offcourse off.

I have to say that even though I've owned both a svt and the aggie for a long time, I'm a complete newbie when it comes to tube swaps and differences in theyre sound, so please educate me :-)

I was wondering if I could put in some different tubes to tame it a bit? I checked what was in and this is what i found, seen from front of preamp:

Right: ElectroHarmonics 12ax7EH (made in Russia) 0406

Left: JJ ECC 83 s

I saw one guy here saying that 5751 tubes was good and warm in there.

Any opinions appreciated

tombowlus · #2 09-02-2010, 07:57 AM

Here is a link to an old thread which is right on point and which you should find useful.

If you are trying to tame the highs, then a pair of Mullards may help. Telefunkens should smooth things out, but would retain a similar amount of overall high-end content, most likely.

Tom.

BiigM · #3 09-02-2010, 11:55 AM

Thank Tom. Good link, I missed that one in my search.

Anyone else has anything on this.

The 5751 tubes sounds like they would be cool, but I don't know if the gain would be too low?

jeffjones · #4 09-04-2010, 09:41 PM

With the CA9, you don't need to worry about gain! I used to use this exact set up, and I really liked the sound of Raytheon 5751s.

Ben Clarke · #5 09-04-2010, 11:54 PM

In my experience, anything made before 1980 or so will be an improvement in some way. On the other hand, if it sounds good with the Treble @ 9:00, who cares?

I pulled Teles out of my McIntosh Mc30s for my old VTBP-201 and am happy I did. I like their overall sound in absolutely everything I've dropped them into.

Ben Clarke · #6 09-05-2010, 12:04 AM

also, if the Presence circuit works like my old version, it's boost only.

BiigM · #7 09-05-2010, 02:34 AM

Yeah the presence is boost only on mine too :-)

I bought some different tubes to try out. I didn't wanna start with with the most expensive so the NOS Telefunkens has to wait a bit :-)

Here's what I got, all are new except for the GE's:

electro-harmonix 12AX7/ECC8
TUNG-SOL 12AX7/ECC83
SOVTEK 12AX7LPS
NOS JAN GE 5751
TAD-Tubes HIGHGRADE Selected 7025 S -Mullard style-

I don't know if these are the right choices for new tubes, but I'm a newbie in the tubeswap game so I was buying based on what I could read on talkbass.

I thought that the stuff i don't use in the Demeter, I could try out in the DB750 i have.

What would you start with?

Ben Clarke · #8 09-05-2010, 11:24 AM

I'd start with the GE or TAD. I've never liked Sovtek or EH 12AX7, but have only used them in hifi and guitar applications. Haven't used any of the new Tungsol...

mbrancalion · #9 09-05-2010, 11:28 AM

I've been using chinese tubes (came with my unit) since 1997.

I had a short experience with Sovtek LPSs, which i didn't like (too "soft").....

Recently, after advice from a competent friend, i put 2 Sovtek WB tubes on.
I'm very satisfied. They took many hours to break in, but after that they opened up in the high frequencies. The lows are much more controlled and tight than before, too.

Ben Clarke · #10 09-05-2010, 09:29 PM

Like strings, there's no right or wrong when it comes to tube selection. I remember back when I was changing out the crossovers in my stereo speakers - the new ones used completely different types of capacitors and also sent more HF energy to the midrange horn. I ended up changing a very sensitive tube slot in my amps. Point is that it all matters, including upstream and downstream equipment.

Try not to obsess about it - it's not worth it. Like I said, if it sounds good and you are satisified, don't worry where the knobs are pointing. Have fun, but if stops being fun and becomes a distraction, take a step back.

tombowlus · #11 09-07-2010, 07:33 AM

Quote:

Originally Posted by Ben Clarke

I'd start with the GE or TAD.

+1, and then I'd probably roll in the Tung-Sol, next.

But, to the extent possible, try them all with an open mind, and don't let other people's opinions sway your own. And don't expect huge, in-your-face changes. We are talking subtle differences, here, for the most part.

Tom.

laklandplayer · #12 09-07-2010, 09:21 AM

Call James Demeter, ask him. He is a wealth of info and has done extensive research on what works best in his preamps and why. I blew a lot of money trying to find the "right" tubes before I talked with him. James has helped me re-tube my vintage '85 201, and it still sounds great, the best investment I ever made.

BiigM · #13 09-07-2010, 09:57 AM

Thanks for the advice guys.

I did write Demeter, and they answered quickly, but there wasn't much advice on tone :-)

I'm gonna try out the GE and the Tad first as you recommend. I'm looking forward to see if I can even hear a difference :-)

Based on the fact that I would like a little less high end would still start with those?

I'm offcourse aware that any difference will be subtle :-)

Oh by the way, I got a mullard reissue too. Someone mentioned in another thread that they might be the thing for me.

James Simonson · #14 09-07-2010, 10:05 AM

The Demeter is a killer pre! Probably the fastest, clean, bright (good bright) pre out there.

GE tubes were incredible in my SVT. I had it "freshened up" and it lost all the vibe. >:/

Vintage prices are high but pre tubes should last you a long time.

JJ Mullard makes a great reissue. I threw two in my mesa walkabout and it was a little dirtier with more mid character.

BiigM · #15 09-08-2010, 12:50 PM

just a little update.

I tried some of the tubes today.

First I have to say the differences are really subtle. So this is what i think I heard :-)

I was only changing V1

I tried the Tad 7025 first. Treble was still as pronounced but it didn't sound quite as harsh as with the JJ that was there.

Then the GE 5751. This was what I ended up with. The treble was similar to the TAD but it had a bit more warmth and fattness in the bassfrequencies.

I also tried the Sovtek 12ax7LPS. This one had maybe a bit less treble. But the bass where not nearly as defined as with the two others. The Demeter will never sound muddy, but compared to the other tubes this was anyway the feeling.

So I ended up putting the ge5751 in both v1 and v2, and i'll live with turning down the treble a tad :-)

I hooked up my DB750 right after. Different world. I'm not good at describing sound, but to be the difference is not just in the bassfrequencies but also in the middle. It has this hardness in the mids that the demeter is without. I threw in the Tad in the V1. It didn't make a huge difference, But I thought it sounded overall a bit better. Probably just in my head :-)

Rick Blanc · #16 10-05-2010, 12:47 PM

Any one have a link to a good place to buy tubes?

tombowlus · #17 10-05-2010, 01:12 PM

Doug's Tubes
Tube Depot
The Tube Store

Rick Blanc · #18 10-06-2010, 09:11 AM

Sweet. Thanks

Rick Blanc · #19 10-07-2010, 05:12 AM

Which one of these options, if any, should I choose?

tombowlus · #20 10-07-2010, 06:49 AM

Quote:

Originally Posted by Rick Blanc

Which one of these options, if any, should I choose?

I would probably just roll with the standard, but I suppose there may be some value in the low noise & microphonics test. You don't need high gain, though, and they don't need to be matched.