Tube pre-amp with ss amp?

[JoeE SP9]

One of the reasons I've stuck with ARC preamps is they support every piece of equipment they've ever made. You can send one of their earliest pieces back to them and they will fix, repair, overhaul or simply upgrade it. With ARC there is no such thing as it's too old to fix.

[E-Stat]

One of the reasons I've stuck with ARC preamps is they support every piece of equipment they've ever made. You can send one of their earliest pieces back to them and they will fix, repair, overhaul or simply upgrade it. With ARC there is no such thing as it's too old to fix.

ARC is currently highlighting the "C" update to the early 70s icon, the SP-3.

SP-3

If you were so inclined, my guess is that you could still get the MKIII update or the remote gain control for your 9.

rw

[JoeE SP9]

ARC is currently highlighting the "C" update to the early 70s icon, the SP-3.

SP-3

If you were so inclined, my guess is that you could still get the MKIII update or the remote gain control for your 9.

rw

I've been thinking about the update for my SP-9. It will have to wait until I get my new preamp. I kick myself frequently for getting rid of my SP-3. It was the first piece of ARC gear I ever bought. Selling it was one of the dumber things I've done. That's why I'm not selling my SP-9.

[jrhymeammo]

http://thetubestore.com/ru-6h6p.html
I just ordered some. They should work, but who knows.. If they do, then here is what I think. Since availability of these tubes are so scarce, people are keeping their mouth shut. After all, we all gotta lookout for ourselves first.
I'll post an update one I get them going.

PEACE.

[jrhymeammo]

http://thetubestore.com/ru-6h6p.html
I just ordered some. They should work, but who knows.. If they do, then here is what I think. Since availability of these tubes are so scarce, people are keeping their mouth shut. After all, we all gotta lookout for ourselves first.
I'll post an update one I get them going.

PEACE.

Nope, they do not work. In last 2 weeks, I've invested over 100 bucks on tube. Man, hope they'll take them back. They better.

[jrhymeammo]

Hey Bernd. how about these for you? http://www.audiotriodes.com/en/shop/...oduct/253.html

[Bernd]

Thanks for the tip, but I don't use 6N6 tubes. I will keep this one in mind though in case the question comes up again.
And you're right we need to share info like this one.
Hope the new ones you've ordered work for you.

Peace

Bernd

[WILLIAM C WALDECKER 3RD]

I have been intrigued by the tube sound for a while (I remember what they sound like from my childhood years), but I only upgraded to a Musical Fidelity amp driven by a Rotel pre-amp a couple of years ago. On the whole, I'm happy with this set up, but for some types of music, ie classical vocal, violin etc, I wonder if I would get a warmer sound if I introduced tubes? I don't have the money to change the whole set up, or to set up an alternative system, but thought I might experiment with a tubed pre-amp just for certain uses.

Has anybody else mated a ss amp with a tube pre-amp? Is this a successful comination?

Thanks.

Hey Stanley, i am currently using a Balanced AudioTechnology VK 3i tube preamplifier with a pair of Odyssey mono extreme SE monoblock power amps that are solid state and in my opinion the combination offers the best of both Worlds. thanks....WCW III

[StanleyMuso]

This has certainly turned into a very interesting discussion, and certainly encourages me to try it out.

How complicated is it to keep things balanced? Someone told me it keeps constant fiddling to keep tubed amps running properly because tubes don't wear out at the same rate. Is this true?

And it certainly appears that it is hard to find replacement tubes at times.

Sorry to be such an ignorumus, but one more question. What sort of life expectancy can I expect from a set of tubes?

[Bernd]

This has certainly turned into a very interesting discussion, and certainly encourages me to try it out.

How complicated is it to keep things balanced? Someone told me it keeps constant fiddling to keep tubed amps running properly because tubes don't wear out at the same rate. Is this true?

And it certainly appears that it is hard to find replacement tubes at times.

Sorry to be such an ignorumus, but one more question. What sort of life expectancy can I expect from a set of tubes?

Good on you.
The signal tubes in a pre-amp (if not the obscure type) are plentyful and easy to source. As for fidling with tubes your someone most likely talked about power tubes. Different to the small signal tubes in a pre.
Life expectancy depends on many things. New stock I would say anything up to 2000 hours. Often much longer. NOS (new old stock) between 2000 and 10000 hours. Harder to find, but often sound nicer.
Good luck and welcome to the warm glow.

Peace

Bernd

[Mr Peabody]

I haven't had my gear long enough to be sure about the balance question but it sounds like bunk to me. A light bulb stays lit until it goes out. I personally plan to replace all the output tubes if one goes out because they went in at the same time. This would seem to limited any imbalance problems as well. If you stick with a known manufacturer who stocks the tubes you shouldn't have any problem finding them. I'm not sure on single ended tubes but my manual estimated 5000 hours or so on tubes. If you buy ARC or BAT which uses the Russian 6922, they are said to last about 10,000 hours. If that tube is the reason the new ARC gear sounds like it does, I'd avoid it like the plague.

[E-Stat]

If you buy ARC or BAT which uses the Russian 6922, they are said to last about 10,000 hours. If that tube is the reason the new ARC gear sounds like it does, I'd avoid it like the plague.

I think you are referring to the 6H30 tube, not the venerable 6922.

rw

[Mr Peabody]

E-stat, you are correct sir, thanks for pointing that out. I double checked the BAT and ARC preamps use the 6H30. This is the one called the "super" tube. I haven't heard any BAT but the ARC preamp I auditioned I would not keep as a gift.

[JoeE SP9]

E-stat, you are correct sir, thanks for pointing that out. I double checked the BAT and ARC preamps use the 6H30. This is the one called the "super" tube. I haven't heard any BAT but the ARC preamp I auditioned I would not keep as a gift.

What was the model number of the ARC you didn't like? Just curious. If it was one of their SS models I can understand.

[Mr Peabody]

The ARC preamp I listened to was the LS17. I brought it home with their 150 wpc solid state amp, I forgot the model, it was the digital switching amp. The sales guy actual let me try his out. He uses it with a SP-9.

[E-Stat]

The ARC preamp I listened to was the LS17. I brought it home with their 150 wpc solid state amp, I forgot the model, it was the digital switching amp. The sales guy actual let me try his out. He uses it with a SP-9.

Did you happen to listen to the LS-17 with your C-J amps?

rw

[Mr Peabody]

No, I only listened with the ARC power amp. My disappointment with the ARC kept me searching for tube gear which eventually led me to C-J, and after that I stopped looking. I really find the C-J musically satisfying.

[E-Stat]

No, I only listened with the ARC power amp. My disappointment with the ARC kept me searching for tube gear which eventually led me to C-J, and after that I stopped looking. I really find the C-J musically satisfying.

Perhaps what you didn't like about the ARC stuff was the SS switching amp, not the tube line stage.

rw

[Mr Peabody]

Possible, but I have my doubts. I also listened to their integrated and a few other pieces, not at home, and some of the same characteristics existed. The sales guy uses the SP-9 and the solid state amp, I was going on his recs and what I could possibley afford. The ARC sound gives me the impression of gray and industrial. I've heard older ARC that didn't give me that impression. I know ARC has a good rep, it would be interesting to see what their fan base thought of the new sound. Have any of you had the chance to hear either of these pieces?

[E-Stat]

Possible, buI've heard older ARC that didn't give me that impression. I know ARC has a good rep, it would be interesting to see what their fan base thought of the new sound. Have any of you had the chance to hear either of these pieces?

Actually, the SP-6C preamp from 1981 was the first model to crossover to the "yang" side as HP would say. I bought one having heard his SP-6B originally. It was a tad on the lean and cool side. The later SP-6E, SP-8, and SP-10 models "fixed" that. The first SP-9 was likewise a cool character. I had an SP-9MKII and had the factory update it to the MKIII which added some apparent lower midrange output or warmth along with a bit more resolution.

FYI, all of C-J's new designs also use the 6H30 tube. Starting with the flagship ACT2 and including various models of the CT (composite triode) family.

rw

[Feanor]

Perhaps Geoffcin would back me up on this. Anyway, I'm getting on very well with my Adcom GFP-750 used in passive mode in combination with a pair of Monarchy SM-70 Pro's.

The viability of a passive preamp / power amp comb depends on the preamp output power amp input impedances -- or so I' given to believe. Short interconnects are desireable, though in my case I'm using 6 foot, balanced interconnects with no problems I can hear. (The Monarchys used as monoblocks prefer balanced inputs for optimal operation; there again I can't say I understand the techincal explaination).

How other than the impedance thing, my question is: how could a tube preamp be better than "no" preamp? My pet theory is that tubes added enough pleasant, low-order harmonic distortion to mask the unpleasant, high-order harmonic distortion that S/S cause, especially those that use a lot of feedback. This means that the tubes are actually adding distortion to produce their euphonic effect.

[E-Stat]

The viability of a passive preamp / power amp comb depends on the preamp output power amp input impedances

This is the first of three factors that determines compatibility. Low output impedance of the source is also desirable to provide a suitable input to output multiple. See attached link for calculator to determine potential HF rolloff.

DACT calculator

Short interconnects are desireable, though in my case I'm using 6 foot, balanced interconnects with no problems I can hear.

Balanced or not, the second factor is cable capacitance. The lower the better.

How other than the impedance thing, my question is: how could a tube preamp be better than "no" preamp?

The final factor is gain. Some folks say they lose dynamic "punch" with passives. I think they simply don't have enough gain. My CDP has a 4 volt output driving 1.3 volt sensitivity amps. I can clip them at will.

rw

[Feanor]

This is the first of three factors that determines compatibility. Low output impedance of the source is also desirable to provide a suitable input to output multiple. See attached link for calculator to determine potential HF rolloff.

DACT calculator

Balanced or not, the second factor is cable capacitance. The lower the better.

The final factor is gain. Some folks say they lose dynamic "punch" with passives. I think they simply don't have enough gain. My CDP has a 4 volt output driving 1.3 volt sensitivity amps. I can clip them at will.

rw

Perhaps I'll try some of the math sometime. I do know that the Monarchys' input impedance is supposed to be a good match for passive preamps but I can't quote the spec offhand.

I find the "punch" of the Monarchys at least as good as their predeceasor, a Bel Canto eVo. And I never use a volume knob setting higher than 3 o'clock, necessarily less than unity gain. As for HF roll-off, maybe I just don't hear it as I'm deaf much above 10kHz.

[E-Stat]

Perhaps I'll try some of the math sometime.

All the calculator needs to display response curves is:

1. Amp input impedance (kohm)
2. Cable capacitance (pf)
3. Attenuator resistance (kohm)

edit: Unless I'm playing a particularly low level recording like a Telarc, I usually get full output at around -12 db.

rw

[Feanor]

All the calculator needs to display response curves is:

1. Amp input impedance (kohm)
2. Cable capacitance (pf)
3. Attenuator resistance (kohm)

edit: Unless I'm playing a particularly low level recording like a Telarc, I usually get full output at around -12 db.

rw

So ...

• Monarchy SM-70 Pro amp input impedance is 100kOhms;
• Blue Jeans balanced cables are 13pF/foot, hence 78pF for 6 foot
• Attenuator resistance is -- what? my Adcom GFP-750's output impedance, presumably at 0 dB attenuation, is 1.2kOhms, which is much lower than the calculatior allows.

It would seem there is essentially zero attenuation any where in the audible range. Right??