Eros vs. Reduction?

[alejon]

Good afternoon everybody,

I am about to decide which kit is going to be the right one for me, Eros or Reduction+Integration. I am using a LOMC 0.25mV cartridge with 1:20 SUT. In the future, I may think of going to MM 4.0mV cart.

I've got few questions and very thankful if somebody could take a minute to answer.

1) What topology these two phono amps are using? Like for example, two gain stages, or a gain stage+SRPP buffer etc.
2) What are your listening impressions (who had listened to both of them)?
3) Background noise level? - with the LOMC cart it is quite important.

OK, great thanks in advance!

Best regards,
alejon

[Paul Birkeland]

1) What topology these two phono amps are using? Like for example, two gain stages, or a gain stage+SRPP buffer etc.

Both are two gain stages, though that tells very little of the story.  (By the way, we haven't put SRPP in any of our products for close to 15 years now)  The reduction is two cap coupled 6922 voltage amplifiers with passive RIAA equalization.  The Eros is two stages directly coupled with an EF86 pentode driving a 6922.  The Eros comes stock with C4S loads for each stage and our hybrid shunt regulator.  The Reduction is restively loaded with an unreglated high voltage supply in stock form, with the integration each stage gets a C4S load, and the high voltage supply is afforded a high voltage solid state shunt regulator.

3) Background noise level? - with the LOMC cart it is quite important.

The Eros is better in this regard, though the noise picked up by a SUT will tend to be greater than the noise floor contributed by either preamp.

[alejon]

Dear Paul,

Many thanks for your reply!

OK, Reduction has two gain stages using two triodes whereas Eros has two gain stages with a pentode in the first stage and a triode in the second.

Please excuse my stupid questions, I am a newbie in tubes. I have just accomplished a Speedball Crack, that's all I know basically. It sounds beautiful, and the design simplicity impressed me a lot. The fewer components in the signal path the better is the sound, this is my firm understanding - valid for solid state stuff as well. The Crack sounds so good it made me think to purchase a Bottlehead phono amp kit.

BUT the most important is - what is the sonic difference between a triode and a pentode tube? I've heard mainly negative things about  pentode tubes. It may offer a higher gain but on the cost of other things. Is this correct or wrong?

Unfortunately, I can't purchase and evaluate both kits myself, Reduction and Eros, due to high cost. So I will need some help here.

Another thing, a bit off-topic, is there a particular reason NOT to employ SRPP in the Bottlehead designs? Some say the SRPP is the ONLY way to go, sound-wise... and these are not your competitors, if that matters.

OK, thanks in advance!

Regards,
alejon

[Doc B.]

The Eros and Reduction have the same family sound. The Eros has better resolution and a sense of better bandwidth, which can also be perceived as sightly better dynamics and a slightly more natural sound. There is a valid reason that the Eros costs more. The power supply is more sophisticated and this translates to better sound.

My advice is to disregard audiophile homilies like "fewer components, better sound". That's far too simplistic a statement to have any value. It implies that the best sound system is no system at all, so just quit listening to music.  I would suggest considering a quote often attributed to Einstein - "Everything should be made as simple as possible - and no simpler".

It is interesting to note that the closest documented statement by Einstein to this effect was actually not that simple -

"It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience."

[Paul Birkeland]

BUT the most important is - what is the sonic difference between a triode and a pentode tube? I've heard mainly negative things about  pentode tubes. It may offer a higher gain but on the cost of other things. Is this correct or wrong?

For small signal applications, the pentode will offer higher gain at the cost of increased design complexity and increased overall cost.  For an actual power amplifier, these generalizations become a bit different.  I find that the Eros is more resolving and more neutral, while the Reduction has a bit more of the traditional triode sound that's a bit rounder in character.

Another thing, a bit off-topic, is there a particular reason NOT to employ SRPP in the Bottlehead designs? Some say the SRPP is the ONLY way to go, sound-wise... and these are not your competitors, if that matters.

SRPP was huge in the 1990's (when we used it), but ultimately it did not take all that long to abandon it in favor of a current source loaded grounded cathode amplifier.  For reference, I think the SRPP driver stage lasted maybe 1-2 years in one product, while the CCS loaded voltage amplifier has remained ever since.  SRPP can be useful when you need a lot of drive current but don't have a lot of excess high voltage current (implied here - if you're using too small of a power transformer in your power amplifier).  In the early commercial designs, it is my opinion that SRPP was used as a way to mate a 12AX7 to a 2A3 or 300B, where some of the excessive gain was traded to buff up the underwhelming current available. 

I cannot think of any valid reasons to put SRPP into a phono preamp, but I can think of many, many reasons not to.

-PB

[alejon]

Dear Doc,
Dear Paul,

Many thanks for your replies! Yes, you are both right and I trust you on this one. For the Crack being SO GOOD you got unlimited credit here. Eros offers 10db more gain, I am going to evaluate soon whether I really need it.

While we are here anyway may I ask another question - what is the "headroom" of Eros? Would it work fine with 4.0mV MM cartridge or needs "attenuation"?

OK, many thanks again!

Best regards,
alejon

[Paul Birkeland]

4mV of signal level will work much, much better with the Eros than it would with a Reduction.

-PB

[Sugar Man]

EROS!

I just finished my Eros and it is REALLY good. With the Stereomour II/Seduction combo I didn't have enough volume for my Sumiko Blue Point Special High MC (2.5mV).  The Eros changed all that and was a BIG step up in sound quality - even the wife is raving about the sound. The sound is really balanced with AMAZING high and low end.  Finally feel like the Eros is allowing the RP 6 and Blue Point Special to deliver all they got. 

The Eros is worth every penny - and then some.  Super satisfied.  Well, might need to look at a Blackbird and some EML Meshplates...

[Rocketman248]

I was thinking about making the upgrade from the Reduction to the Eros, and the upcoming Leap Year sale has made that decision much easier.  I'll be ordering one on Monday. 

[alejon]

... and the upcoming Leap Year sale has made that decision much easier.  I'll be ordering one on Monday. 

Yeah, this and Sugar Men's wife finally got me to surrender. Ordered one now, hope it comes with the IERC shields.

[Rocketman248]

My Eros arrived last week, and I finished it yesterday.  I can happily report that it sounds amazing.  I was sitting in my living room with a big stupid grin on my face as Pink Floyd's Welcome To The Machine filled the room.  Another happy customer here.