[Goosepond]

In my adventurous search here and on Audiogon for an appropriate amp for my mini's, I have come upon a funky looking retro styled Atma-Sphere OTL 30 W amp that supposedly doesn't like low impedance speakers at all.

So my question is, what kind of impedance curve does the 87db 8 ohm mini's have and are they considered to be easy to drive speakers?

Thanks,

Gene

[bhobba]

From what Bob has written they don't have any wild impedance dips etc so they so they should be an easy drive.

Thanks
Bill

[phoenix_rising]

In my adventurous search here and on Audiogon for an appropriate amp for my mini's, I have come upon a funky looking retro styled Atma-Sphere OTL 30 W amp that supposedly doesn't like low impedance speakers at all.

So my question is, what kind of impedance curve does the 87db 8 ohm mini's have and are they considered to be easy to drive speakers?

Thanks,

Gene

Hi there,

It largely depends at what volume you want to drive them. I had a look at the specifications for the amplifier you are considering and it will drive the mini, the mini is a relatively easy load to drive but it is not super efficient so as long as you don't want really loud (volume wise) you will be fine with it.

If you were using a SS amp I would have said feed it a minimum of 100 watts. I am purchasing the mini's as well and I will be feeding mine with a 250 watt SS amp.

Phoenix

[Goosepond]

Thanks phoenix,

It seems there are watts and then there are watts. One amp's watts don't seem to be the same as another amp's watts, if you can believe all the hype.

Nelson Pass talks about the importance of that 1st watt.

That Atma-Sphere amp only has 30 watts and another amp I am considering is Vinnie's Sig 30.2 which is also 30 watts. While both are quality amps, I wonder if at any time they would come up short. I'm not one to to try to knock the walls down. I'm too old for that. But for the few times when I do want to crank it up, it would be nice to know that I could do it. I've got a small listening room so it shouldn't take too much.

I don't know what's a nice reserve. I look at a lot of healthy McIntosh's and McCormack's on Audiogon.

And on Bill Baker's Response Audio site for his Jolida 801A modded integrated amp, he references Bob's comment about being really impressed with it's performance with the SP Tech speakers. And the Jolida is 70 watts.

Luckily I've got time to mull it all over. Actually it kinda fun anticipating what I'm in for as this will definitely be new territory for me.

Gene

[Aether Audio]

Guys,

Ooops...wrong thread.  Sorry.

By the way... the Minis impedance is easy to drive.

Take care,
-Bob

[opnly bafld]

Gene,
I heard my Mini's with a 25w PP in a med/small rectangular room.
They played fairly loud, but I'm not sure I would be happy with @25w/ch as my only amp.
IMO more headroom would be nice just in case.
Having said that, I could see where some people could be content as long as they had enough gain before the amp.

That really cleared things up didn't it? 

Lin

[Goosepond]

Thanks Lin,

What you didn't say is what you ARE driving your mini's with. 

Gene

[opnly bafld]

Thanks Lin,

What you didn't say is what you ARE driving your mini's with. 

Gene

When I first received them 100w/ch SS drove them well,
when I get them back (a friend has them now) I will try a 200w/ch hybrid amp. 

Lin

[yo2tup]

When I get the mini's (which should be soon according to Bob) I will try them with a couple tube amps..... a 50watt Bella Extreme 3205p and a 7watt 300B amp 


Bob, I responded to the emails you sent earlier.   Please check, thx. 

[Goosepond]

Well, by default, unless I buy something before the mini's get here (maybe in March), I'll use a Sony ES 90 wpc SS amp and also try my Moth 2A3 SET 3 wpc amp.

Gene

[bhobba]

Well, by default, unless I buy something before the mini's get here (maybe in March), I'll use a Sony ES 90 wpc SS amp and also try my Moth 2A3 SET 3 wpc amp.

Keep us posted Gene.  That SET combo sure sounds intersting.

Thanks
Bill

[Goosepond]

Well, I guess it's time for an update.

There's nothing like going overboard. I "settled" for a Spectron Musician III SE at 600W into 8 ohms. Talk about overkill. But I guess I'll never have to worry about coming up short. 

I got it this Monday and had no choice but to hook it up with what I've got now which isn't much. But at least it's making my 15 year old speakers sing for now.

I've also been looking for a good affordable preamp. I ran into the BAT lineup and while they are obviously good, most of their stuff is not affordable, at least not for me, at least not for now. So I've taken another tact. I decided to get something used that should do the job for now while I try to save some more pennies.

Yesterday I bought a PS Audio PCA-2 preamp on the Head-Fi forum and today it looks like I'll get the external power supply for it from a seller on Audiogon. Ain't the Internet great!

It's something called the HCPS (High Current Power Supply I think). Anyway, all that's left now is for Bob to finish making my mini's.

Lot's to look forward to. 

Oh yeah. I sold my Moth SET so that helps to ease the pain of this madness.

Gene

Well, by default, unless I buy something before the mini's get here (maybe in March), I'll use a Sony ES 90 wpc SS amp and also try my Moth 2A3 SET 3 wpc amp.

Keep us posted Gene.  That SET combo sure sounds intersting.

Thanks
Bill

[Double Ugly]

Congrats on the new amp, Gene.  If what I heard in Denver is any indication, I doubt you'll be disappointed with the pairing.

I hope to have a pair of updated Timepieces soon, at which time I can finally answer long-standing questions about how the Musician III SE sounds in my system.

So I guess the race is on, Gene.  Hopefully I can answer questions about the Spectron/Timepiece pairing before you're able to address those sure to come about the Minis.   

[konut]

This was originally posted on another SP thread and got lost in the shuffle.

Quote from: SP Pres on Yesterday at 08:54:09 am
  I don't know what the phase angle of the M&Ds are, but I can tell you that the Rev's never exceed -35 degrees at ANY frequency.  A difference of 10 degrees may not sound like much, but to an amplifier that's a lot.

 -Bob



 This begs the question, what is the phase angle of the Minis?

[Double Ugly]

This was originally posted on another SP thread and got lost in the shuffle.

Quote from: SP Pres on Yesterday at 08:54:09 am
  I don't know what the phase angle of the M&Ds are, but I can tell you that the Rev's never exceed -35 degrees at ANY frequency.  A difference of 10 degrees may not sound like much, but to an amplifier that's a lot.

 -Bob



 This begs the question, what is the phase angle of the Minis?

I'm sure Bob will answer soon, but if this post is any indication, it's probably similar.

There was a phase angle issue early in the Timepiece 2.1 production run, and Bob's been careful to minimize it since.