amp suggestions for Beepre?

[Jamus]

I took advantage of the generous Black Friday sale to score a Beepre. I recently built a Crack w/speedball and have been having withdrawals from the solder fumes. Time for another build!

I'm struggling a bit to settle on a power amp. I'm looking to spend under $1k for a solid state amp. Are there some general guidelines for the spec sheet that I should be focused on in order to make sure the amp plays nice with the Beepre? I'm aware the input sensitivity should be over 10-20k ohms. I'm lost on the sensitivity and db gain specs I should be looking for.

Currently looking at Emotiva XPA-2 and Parasound a23. Not sure if these would work and open to all recommendations.

I should add the current speakers are Energy RC 70s but I will likely upgrade within the next few years (recommendations welcome here too). I'm leaning towards Ascend Sierra towers or Salk Songtowers so I want to be sure the amp choice is good for the long range goals as well as short term needs.

Thanks in advance!
Jamus

 

[Paul Birkeland]

The big mismatch that we see often with the BeePre is a very high power amplifier with very efficient speakers.  This is completely eliminated if you purchase a power amplifier with input level trim controls. 

The input impedance of the amplifier should be greater than 600 Ohms. 

The RC-70's are a 92dB sensitive speaker with a couple of 4 Ohm dips.  A 100W amplifier will produce enough SPL to drive you out of the room, and 50W is likely to still be an absurd amount of power.  Putting a 300W amplifier on 92dB speakers would not be a good match, though you could use -12dB inline attenuators at the inputs of the power amp to mitigate the issues you'll face.  I would personally go for a Gainclone until you find the next pair of speakers that you want.  A gainclone should work nicely with the monitor speakers that you are interested in, and ought to be fine with those transmission line towers also in a room that isn't too big.

 

[Jamus]

Thanks Paul. I'm definitely not married to the idea of any of the amps I mentioned. I had it stuck in my head that a tube pre and ss amp would be a "best of both worlds scenario" but maybe that's off base too. I'm really just interested in getting the most out of the Beepre. Perhaps a more appropriate question is what amp (either tube or ss) would you recommend between the Beepre and 92db speakers for under $1k?

 

[Paul Birkeland]

I would see if you could borrow a Stereomour from a Bottlehead in your area.

-PB

 

[Jamus]

Is there a major advantage to running the Beepre with the Stereomour vs the Stereomour alone?

 

[Paul Birkeland]

Yes, we have had several customers use this configuration, and they all are unanimous about the positive effects of having the BeePre in the chain. 

The Kaiju would solidly meet your needs, but it's a fair ways out of your budget. 

 

[denti alligator]

What about the Seductor?

 

[Jamus]

Thanks for the suggestion! not sure why I didn't consider that earlier. I suppose you could even run 2 as monoblocks if the speakers are not very sensitive. would that be necessary with 92db sensitive speakers?

 

[Paul Joppa]

Thanks for the suggestion! not sure why I didn't consider that earlier. I suppose you could even run 2 as monoblocks if the speakers are not very sensitive. would that be necessary with 92db sensitive speakers?

Yes they can be bridged to monoblocs to double the power.

There's a current thread in the Kaiju forum with a similar question about how much is enough power. Bottom line, 92dB speakers usually want 2-10 watts, depending on how loud you want to listen and what your music is like and your room and a few other variables.

 

[Jamus]

The input impedance of the amplifier should be greater than 600 Ohms. 

Did you mean "input sensitivity, less than 600mV"? 600 Ohms seems low, I was thinking i needed 10x the output impedance of the pre. For input sensitivity I've seen others on this board recommending -12db attenuation for amps that are 550mV sensitive.

 

[Jamus]

Thanks Paul (Joppa)! I was shocked to read that figure of 2-10 watts. Why in the world would anyone want/need a 300 watt amp in their system?

To answer your questions my room is approx 12'x15' with speakers on a short wall and listening approx 9' away from speakers. I usually listen on low-moderate volume (subjective I know but I certainly wouldn't say loud). Musical taste is all over the map from female singer/songwriter to 60's soul to indie rock to electronic dance music.

 

[Paul Birkeland]

Did you mean "input sensitivity, less than 600mV"? 600 Ohms seems low, I was thinking i needed 10x the output impedance of the pre. For input sensitivity I've seen others on this board recommending -12db attenuation for amps that are 550mV sensitive.

600 Ohms is very low, but there are some amps with 600 Ohm input transformers, though this is fortunately not that normal these days.  10K is generally as low as you'll find, and the BeePre is well suited to drive such loads.

Input sensitivity has a fair amount to do with gain, an amplifier with a 600mV input sensitivity is likely a terrible choice. 

-PB

 

[Paul Birkeland]

Thanks Paul (Joppa)! I was shocked to read that figure of 2-10 watts. Why in the world would anyone want/need a 300 watt amp in their system?

To answer your questions my room is approx 12'x15' with speakers on a short wall and listening approx 9' away from speakers. I usually listen on low-moderate volume (subjective I know but I certainly wouldn't say loud). Musical taste is all over the map from female singer/songwriter to 60's soul to indie rock to electronic dance music.

When you hear a 300B amp on your speakers, you'll start to understand.  Your room size isn't particularly large (unless you have very high ceilings), so 4 Watts isn't unreasonable.  The Seductor isn't a bad choice, but the Stereomour sounds a bit better.

-PB

 

[Jamus]

Thanks again. I appreciate your time and patience as I stumble my way through all of this.

 

[Jamus]

I thought I would close the book on this in case anyone is interested. I ended up going with the Kaiju (sucker for a good sale). Going all in with the 300b tubes! I've also decided to go with the Blumenstein Orca system based on reviews here. Should be a sweet system! Now just need to finish my Beepre...

 

[Doc B]

Thank you for the order! The Kaiju will rock with the Orcas.

 

[marco08]

just a word on my journey :

on both ends, i got a beepre and a fairly efficient unfiltered wideband speaker (DIY Davis MV ONE clone, 94db sensitivity), and I used to have a Coda S12 amp. Nice amp, balanced and running in class A for the first 20w, but a bit to analytical for me, even with the 'pre in front of it.

i realized a dream, bought and refurbished a 1962 Mc225 and.... almost magic !!

on the usability side, power is plenty enough for a 4x10m room, and the gain adjustment allows to fine tune the noise floor issues between the two tube elements, even with sensitive speakers.

i find the lower and mids to die for. best combination and musicality of  the various setups ive tried in 25 years.

I still have a small issue with the top end of the range, some "ringing/sibilance" on high pitched female voices. I do feel it has something to do airborn microphonics, even if my bottles are equipped with herbies'rx. I'll try and put additional weight on them, using teflon coated brass brushings and see if it helps (couldn't find the vinyl covered lead rings in europe at a decent price)

but what a combination !!!