Would you buy an entry-level tube preamp.....?

[jjmatrix]

Apr 23, 2013 16:49:45 GMT -5 KeithL said:

What features do you consider really necessary, and what would you be willing to spend to get them?

Some features I'd like:
- 2 inputs max
- easily accessible bias control
- 20-30W power
- min 4 ohm load
- around $400 mark

Would you want to roll your own tubes, or would you want us to pick out good ones for you, or both?

Tubes included; matched the best you can.

Do you like a certain type of tube, or a certain tube number?

Nothing in particular; whatever Bob recommends for an entry-level tube amp ;D

Do you prefer NOS tubes, or modern Russian ones, or other modern ones?

Modern ones.

What kind of equipment would you be planning to use it with?

Source: Pro-Ject Turntable via Carver C2 preamp and digital files via PC>>JRiver>>UMC-1 (for now).
Speakers: Axiom M80 - 4 ohm with 95dB sensitivity.
Bi-Amping may be an option (Tube-amp for mids/highs and UPA-1s for low end)

I am currently evaluating a Sophia Electric Baby Amp (www.sophiaelectric.com/); I am very impressed. You better hurry ;D.

[Ref]

An entry level tube preamp would be nice, but a high-end one with Emotiva's pricing would be better.

[knucklehead]

My first receiver was a tube model from 1966 - a Sansui 500A. If this new tube powered preamp is cheap enough I might give it a try but I was pretty happy going from tubes to solid state. More power and more reliable.

[Chuck Elliot]

If you're going to go with a "tip-toe in the tulips" approach, a small integrated might be better. It could always be split-able to afford adding a bigger power amp later.

I like Boom's modular approach, but not for a simple product. When you provide the future expandability, you must supply the infrastructure and that doesn't come for free.

I think that most who are looking for a killer tube pre-amp want something that is way above Keith's proposal.

Me, I want a killer power amp, but look at this as a good starting point for Emotiva.

Chuck

[thompson12]

I'd be willing to give it a try, i seen tubes that light up blue that would be cool

[thorcorps]

I don't have any interest in an entry level unit. I have hybrids and solid state preamps already, but I think an entry level unit would still sell really well (just not to me). I think Emo should select the tubes.

If you can make it match aesthetically, it should be part of the Exec system/line discussed previously.

[DYohn]

I wouldn't personally be interested (although hit me with a high-end 2-channel valve pre and we can talk.) But to answer your questions, I believe most tube neophytes want something they can plug and play, but that they can roll if they decide to, so it should probably use relatively cheap and available tubes like 12AX7's or 6922s. I'd ship the pre with decent Chinese or Russian tubes but make them easily accessible for swapping. I suspect most users would want three or four inputs, and output designed to drive solid state amps. A nice mid-level pre might include a phono preamp or a built-in DAC input - although designing the pre so it is easily integrated with the XDA-2 and a stand-alone phono pre would both increase Emotiva sales and system flexibility.

[Golden Ear]

Tube preamp known to be sound smooth and diffuse sound field. I am interested!

[milsap195]

I had to role the cheap tubes in my Vincent. I went with the Grant Fidelity Ps Vane mk and it made a world of difference. I would pay more up front for better tubes. Emotiva has not skimped on any thing, don't start with cheap noisy tubes.

[guitarforlife]

I would be interested. For sure.

I would like a Phono stage as well as tone controls that can be bypassed if you do not want to use them.
But tone controls are for me.

YA,YA I know "true" audiophiles do not want them.
OK I'm not a true audiophile.

I would like tubes that are easy to get to like sticking out the top.

Three inputs would be fine including the phono.

A remote for volume is fine.

And I would say $800.00 to $1000.00.
Just let me know when it is done I'll get you the money.

[cheapthryl]

yes I would be interested . remote yes , Phono yes , ht bypass would be ok also. Let me know when .

[Axis]

Apr 23, 2013 17:55:53 GMT -5 hemster said:

Apr 23, 2013 17:49:21 GMT -5 Boomzilla said:

Preamp tubes are typically biased at the factory via resistors without any variable pot to change the tube bias.

I think axis is talking about self-bias versus fixed-bias (aka cathode bias). From a design features standpoint, BOTH design approaches may or may not have user controls provided to adjust circuit parameters, but fixed bias designs typically do have user controls, and cathode biased designs typically do not.

A number of cathode biased amplifiers provide an adjustment pot for adjusting the quiescent current of the output tubes. A Fisher X-100B is an excellent example of this. Conversely, a number of fixed biased amplifiers provide no means for adjusting the quiescent current at all. An early Scott LK-72 is an excellent example of this type of design.

Hemster, when I read the question "Would you want to roll your own tubes?" I was thinking it would need bias adjustment. It's been 30 years since I have had any tube gear and it was always McIntosh. My preamps were solid state and the amps were tubes. The McIntosh amps power tubes bias could not be adjusted. You could just replace a single bad tube because they did not need to be matched tubes. I was on easy street with all my tube gear. I was looking to get a Rogue Cronus intergrated before I got my Emotiva gear and it required manual bias adjustment. I have never rolled tubes for different tones and would love to do it with this new Emotiva tube gear. Bob Carver's gear has Auto bias and that's where these questions came off the top of my head. Now I know you can roll preamp tubes and not have to worry about bias. I'll wait for the Emotiva tube amp thread to see what they do there. I'm just going to have fun with this.

Thanks guys

Mike

[geebo]

Well, since you asked, I'd have to say I probably would not be interested in tube gear. I'm very happy with my Emo solid state equipment. I don't have anything against it, I just don't have an interest in it.

[hooked]

yes please!

[hemster]

Apr 24, 2013 6:58:15 GMT -5 Axis said:

Apr 23, 2013 17:55:53 GMT -5 hemster said:

I think axis is talking about self-bias versus fixed-bias (aka cathode bias). From a design features standpoint, BOTH design approaches may or may not have user controls provided to adjust circuit parameters, but fixed bias designs typically do have user controls, and cathode biased designs typically do not.

A number of cathode biased amplifiers provide an adjustment pot for adjusting the quiescent current of the output tubes. A Fisher X-100B is an excellent example of this. Conversely, a number of fixed biased amplifiers provide no means for adjusting the quiescent current at all. An early Scott LK-72 is an excellent example of this type of design.

Hemster, when I read the question "Would you want to roll your own tubes?" I was thinking it would need bias adjustment. It's been 30 years since I have had any tube gear and it was always McIntosh. My preamps were solid state and the amps were tubes. The McIntosh amps power tubes bias could not be adjusted. You could just replace a single bad tube because they did not need to be matched tubes. I was on easy street with all my tube gear. I was looking to get a Rogue Cronus intergrated before I got my Emotiva gear and it required manual bias adjustment. I have never rolled tubes for different tones and would love to do it with this new Emotiva tube gear. Bob Carver's gear has Auto bias and that's where these questions came off the top of my head. Now I know you can roll preamp tubes and not have to worry about bias. I'll wait for the Emotiva tube amp thread to see what they do there. I'm just going to have fun with this.

Thanks guys

Mike

Mike, you're correct. What I was talking about - cathode biasing - applies more to amps. It does limit the available current and therefore the power output. Most folks will be happy with self-biasing amp tubes. But not having to worry about matching tubes is nice. It'll be a fun ride with Emotiva, that's for sure!

[reaper60]

Ok, simplified approach here. I suggest you build a tube buffer that allows simple integration to other Emo equipment. Something like a 2RU (or even 1RU) chassis that has simple input and output with a HT bypass. I'm thinking something I can stack between my UMC-200 and my power amps and would allow me to have a more "tubey" sound for 2 channel listening but keep the direct bypass for the HT. Would be even better if connections were balanced or RCA so that when the XMC-1 is finally released I can run balanced from my XMC-1 to the Tube Buffer to the XPA-1's for a complete differential and balanced 2 channel stereo while maintaining my home theater as it stands. I think most people simply cannot afford 2 systems and make serious compromises when considering a complete package. This would certainly help that cause! It would be very cheap to produce and you could sell it at ~$150/$200 and sell them regularly. As mentioned previously, it would be nice to have it be built with real sized components so it could be easily modded as opposed to surface mount.

On a side note, I recently acquired a Jolida JD-9 phono. Very similar design to this (but phono of course). It is one of the most popular and widely selling phono stages due to upgradeability, sound quality, and design. Can you just build me a JD-9 replacement with Emo parts and pieces and include HT bypass so that I can include it in my HT?

[goat1981]

Just built a tube line stage that I love, but would love to see Emotiva build a tube preamp (at any level, entry -- higher end)

[Boomzilla]

OK - Chiming in yet again - Tube buffer? Noooooooooooooooooo!!! Once you've got the buffer circuitry, you're only a volume pot away from a preamp. The preamp CAN be used as a buffer, but the buffer CAN'T be used as a preamp.

Additionally, ABSOLUTELY NO TRADITIONAL TUBE SOUND! We don't need no syrup on our music. The Emotiva tube device must have tight bass, extended highs, and only a touch of tubes in the midrange. Anyone who wants "traditional tube sound" has their pick of antique gear on eBay for cheap. Use the Audio Research (or better Chinese) preamps as models for the voicing.

Now I'll shut up. - Boomzilla

[jmasterj]

Hi Keith,

Yes I would buy a entry level tube preamp from Emotiva. I had already looked into the $386.00 Xiang Sheng 728A tube preamp on sale on ebay.

The only drawback was what to do if the unit needed service. I even went so far as to contact a local shop to see if he would service the unit if I purchased it. He said that he would not.

I like the features on that preamp, it has tone controls, balance, and a bypass switch. The only thing I would like added is a remote and built in headphone amp. The price point was spot on for me.

If Emotiva sold a nice tube preamp to go with their power amps I would definitely buy that over a solid state preamp.

I'm currently on hold waiting to see what Emotiva and Bob Carver come up with. I already know that I will be purchasing something from Emotiva. I just don't know what yet. Your Move...

[monkumonku]

Apr 24, 2013 9:31:01 GMT -5 Boomzilla said:

OK - Chiming in yet again - Tube buffer? Noooooooooooooooooo!!! Once you've got the buffer circuitry, you're only a volume pot away from a preamp. The preamp CAN be used as a buffer, but the buffer CAN'T be used as a preamp.

Additionally, ABSOLUTELY NO TRADITIONAL TUBE SOUND! We don't need no syrup on our music. The Emotiva tube device must have tight bass, extended highs, and only a touch of tubes in the midrange. Anyone who wants "traditional tube sound" has their pick of antique gear on eBay for cheap. Use the Audio Research (or better Chinese) preamps as models for the voicing.

Now I'll shut up. - Boomzilla

But if you don't want "traditional tube sound" then what is the point of Emo making a tube preamp? It'll sound close to solid state.