Tube Integrated vs. Tube Amp

hochpt21

I don't know if there is a short answer to this, but I am wondering if there is a benefit to buying a tube amp vs a tube integrated.

As I've been looking, a lot of tube integrateds are close in price to either the stand-alone preamp or amp from the same series. Wouldn't the integrateds be much more? What is the benefit of paying almost double for separates?

I am specifically now looking at a PrimaLuna Prologue 5 amp. I have the ability to connect my phono stage directly to the amp. Would the Prologue 5 be a much better amp than the Prologue 2 integrated? (Which the 5 amp is based off of?)

Is a stand alone amp in general a better amp than an integrated?

Just trying to figure out if it would be wise to purchase the amp and run it off my phono stage, or if there would be a benefit to the preamp stage in the integrated.

Thanks all...

mhardy6647

Well -- you're paying for two power supplies and two cases in the (heh-heh) case of separates, relative to an integrated. The former's probably a good investment. You're also buying flexibility -- you may not want the same manufacturer's preamp and power amp. Or you may be happy with (or able to afford) push-pull EL84 now, but -- I dunno -- maybe push-pull KT150 later.

I still haven't found an active line-level preamp that I really, really liked -- vintage or current production. I have heard some DIYs I could live with -- but I cannot afford them.

Oh -- I'll also add that sometimes the preamp sections of the integrated amplifiers is limiting.

mhardy6647

Oh, I forgot to mention -- in the early days of hobby hifi, it was not uncommon for preamps to obtain their power from a companion power amplifier via an umbilicus. There's one good reason to "outboard" the power supply, of course (isolation of the AC induced power supply hum from the preamp's circuits), but obviously there's that much more draw on the power amp's P/S when it has to feed a preamp, too. Not that even vacuum tube preamps require all that much power, but it's still incrementally more.

Here's a Heathkit power amp with outboard P/S. The P/S had octal connectors to supply power to the power amp, and the power amp had a 'slave' octal connector to power a companion (mono) preamp.

Heathkit 1958 W3 by Mark Hardy, on Flickr

hochpt21

Thanks for the info Marky Mark. I'm really close to pulling the trigger on the PrimaLuna 5 amp and just running it off my PS Audio GCPH.

I just want to be fully sure before I make the purchase ya know!!

mhardy6647

I am no expert; I am surprised that better informed folks than I haven't chimed in yet.

hochpt21

DSkip wrote: »

If all you need is an amp, then just get an amp. However, also consider the thought that the tube preamp in the integrated will give you more flexibility for tuning the sound AND will likely be a better preamp than the GCPH on its own.

Makes sense on the preamp, but conversely, in your opinion, would a dedicated amp be better than an integrated amp from the same line/family of amps.

Also why would the primaluna dedicated amp and the integrated amp run the exact same tubes? 4 power tubes plus 2 12AU7's and 2 12AX7's?

Just trying to get my brain around everything.

mhardy6647

It may be that the preamp section is completely passive, and that the four tubes are voltage amplifiers (drivers) and phase splitters in the design.

If (?!?) the Prima Luna integrated has a phono preamp, though -- I am clueless.
I guess I can look 'em up.

Much easier to tell with a schematic, of course

Passive preamps aren't unknown even in storebought (or semi-storebought) amplifiers. The Dynaco SCA-35, e.g., has a completely passive preamplifier section -- except for a mediocre MM phono preamp stage. Of course, the preamp is the SCA-35's weak link -- but that's pretty much irrelevant to the present discussion

DSC_6212 by Mark Hardy, on Flickr

mhardy6647

Looks like, perhaps, they just added a source selector switch and a level attenuator (volume control) to the power amp design(?): http://www.primaluna-usa.com/prologue-two/

EDIT: although several of the specs are different So -- who knows?
http://www.primaluna-usa.com/prologue-five/

EDIT^2: from Kevin Deal's site:

The ProLogue Five starts with the same basic topology as the award-winning ProLogue Two integrated amplifier. Further improvements are realized from new driver and phase splitter circuitry. The result is no need for any negative feedback. This means even more natural tonality and better overall musicality.

https://www.upscaleaudio.com/products/primaluna-prologue-five-power-amplifier

tonyb

Makes sense on the preamp, but conversely, in your opinion, would a dedicated amp be better than an integrated amp from the same line/family of amps.

No really straight answer on that....it depends. Like already said, the int. will give you some flexibility with connections and one less component in the rack. Downside is your stuck with that pre. Primaluna makes some really nice sounding stuff so I wouldn't be too worried about the int. purchase.

tonyb

mhardy6647 wrote: »

I still haven't found an active line-level preamp that I really, really liked -- vintage or current production. I have heard some DIYs I could live with -- but I cannot afford them.

huh ? You've been in this game a long time Mark, what do you mean you haven't found an active pre you like ?

mhardy6647

They all make things sound a little worse than the passive front end. A little more veiled; a little more distant. I would like to have more drive -- the darned "Simple 2A3" amplifier topology needs more drive... but every preamp I've tried (except a constant-current source loaded DIY from Carroll Conklin that wasn't for sale) has cost something sonically to get some more oompf.

... so far...

I am still lookin' -- anyone who wants to bring a good two-channel preamp over to taste-test is welcome, any time! Just call first

Back to the PrimaLunas (PrimaLunae?): Were I the OP, I think I'd call Kevin Deal & ask him about the differences between the Two & the Five

mhardy6647

I think the preamp thing is a good topic for another thread, so I think I'll start one!
Sorry for the temporary hijack!

hochpt21

mhardy6647 wrote: »

I think the preamp thing is a good topic for another thread, so I think I'll start one!
Sorry for the temporary hijack!

All good information!

mhardy6647

preamps are an interesting subject -- way harder to get right than a power amplifier, IMO/IME.