Amplifier for alnico super 6

sugbob21 · « **on:** 26 Sep 2015, 06:27 pm »

Hi,...I know this ha been probably asked before but I have a Decware pre amp and am currently using a Crown 1500 as an amp. Although I am quite happy with this setup, what alternatives are there to replace the Crown that would be worth the investment. Budget would be $1000 area......FYI I need to have the Crown volume set at 3 PM and pre amp about three quarters of the way up to get decent volume. It gets a bit noisy (humming,buzzing) with both having to be set so high.

Dsaldivar · « **Reply #1 on:** 26 Sep 2015, 07:49 pm »

I'm surprised nobody recommends a Musical Paradise MP-301 MKIII. With upgraded tubes is about $400. Great amp! Highly recommended! I replaced the EL34's and sounds great! Check it out!
Dan

sugbob21 · « **Reply #2 on:** 26 Sep 2015, 08:18 pm »

Can the Musical Paradise be used as an amp in conjunction with the Decware as a pre amp ?

FireGuy · « **Reply #3 on:** 26 Sep 2015, 08:29 pm »

Quote from: Dsaldivar on 26 Sep 2015, 07:49 pm

I'm surprised nobody recommends a Musical Paradise MP-301 MKIII. With upgraded tubes is about $400. Great amp! Highly recommended! I replaced the EL34's and sounds great! Check it out!
Dan

+1

Dsaldivar · « **Reply #4 on:** 26 Sep 2015, 08:33 pm »

Hi!
I haven't tried my unit with a preamplifier. I read that setting the volume to the max a preamp can be used. The disadvantage will be another stage before the sound reaches the speakers. I have no idea how the sound changes/degrades. The MP has two inputs. It is an integrated.
Dan

Canada Rob · « **Reply #5 on:** 27 Sep 2015, 12:05 am »

Quote from: sugbob21 on 26 Sep 2015, 06:27 pm

Hi,...I know this ha been probably asked before but I have a Decware pre amp and am currently using a Crown 1500 as an amp. Although I am quite happy with this setup, what alternatives are there to replace the Crown that would be worth the investment. Budget would be $1000 area......FYI I need to have the Crown volume set at 3 PM and pre amp about three quarters of the way up to get decent volume. It gets a bit noisy (humming,buzzing) with both having to be set so high.

Both preamp and main amp at 3/4 on their volume controls should be very loud, especially on a set of Alnico 6. I run mine on a 2 watt SET without pre-amp and rarely venture past 12 o'clock on the volume knob. My DAC has 2.4 volt output. What is the output voltage of your source?

RDavidson · « **Reply #6 on:** 27 Sep 2015, 12:47 am »

I agree with Rob. Another question : What Decware preamp are you using? Is it a preamp (line stage with gain) or it a buffer with attenuation (ie ZBOX)?

sugbob21 · « **Reply #7 on:** 27 Sep 2015, 05:54 pm »

Preamp is the CSP3 . my source is 2.2 output ...its the Pareasound ZDAC2. I just thought that the volume on the pre amp at three quarters would be kind of high....its not that loud, but that's about where it would be for me to enjoy it...so I guess that is OK....only problem is that there is a noticeable buzz or hum coming out of the speakers

JLM · « **Reply #8 on:** 27 Sep 2015, 06:36 pm »

A new member of our small audio club brought his Crown 1500 to the meeting yesterday. We didn't listen to it, but he had the same compliant. (He has decades of experience with very nice gear.)

opnly bafld · « **Reply #9 on:** 27 Sep 2015, 06:45 pm »

You must have the line level output controls turned down on the CSP3.

sugbob21 · « **Reply #10 on:** 27 Sep 2015, 06:52 pm »

Actually line levels are on max

RDavidson · « **Reply #11 on:** 27 Sep 2015, 06:56 pm »

You should have plenty of gain.
Are you using the Crown's crossover?
Does the Crown have user selectable input voltage sensitivity? Pro amps sometimes have this feature, though I see it is spec'd at 1.4Vrms for full output into 4 ohms.

opnly bafld · « **Reply #12 on:** 27 Sep 2015, 07:20 pm »

Something must be set wrong, with those levels you should be blowing your drivers and your eardrums.

RDavidson · « **Reply #13 on:** 27 Sep 2015, 07:48 pm »

Quote from: opnly bafld on 27 Sep 2015, 06:45 pm

You must have the line level output controls turned down on the CSP3.

I see the output voltage is adjustable on the CSP3 from 0-30V. 30V!? Are you sure you have this set to max output? Obviously, you don't want to, but I'm guessing that this is perhaps where the bottleneck in your voltage is happening. I'd set it at 1.5V or 2V output. My guess is that you have it set at something like .5V.

opnly bafld · « **Reply #14 on:** 27 Sep 2015, 09:13 pm »

Is the ZDAC set to fixed output or variable?

Quote from: RDavidson on 27 Sep 2015, 07:48 pm

I see the output voltage is adjustable on the CSP3 from 0-30V. 30V!
I'd set it at 1.5V or 2V output.

From the CSP3 page on Decware.com:

Left and Right Line Level Output Controls.
These are used to dial in the gain of this preamp so that it is perfect with any amplifier. You can adjust the outputs to between zero and six volts. The trick to this is also simple. Just turn them all the way down, turn on your amplifier, raise the master volume to around half way up and then slowly adjust the output level controls to reach your normal listening level. This guarantees a perfect match with any amplifier regardless of it's input sensitivity and power. These can also be used to adjust left/right balance between channels.

sugbob21 · « **Reply #15 on:** 28 Sep 2015, 01:51 am »

Checked again.line levels are set to max .Crown set at 3 o'clock. Fairly loud but nowhere near clipping. Crown meters show 10 watts being used.

RDavidson · « **Reply #16 on:** 28 Sep 2015, 02:58 am »

That's a head scratcher.

10 watts should be pretty loud and there shouldn't be a lot of hiss. The only other thing I can think of is that your tubes may need to be checked. I'd start with the output tubes, since they're the ones doing the grunt work. As you have the preamp's output voltage cranked all the way and yet cleary have gain issues, I think the output tubes must be about dead. Your input tubes and rectifier are likely fine, as they aren't stressed nearly as much as output tubes.

opnly bafld · « **Reply #17 on:** 28 Sep 2015, 03:30 am »

Quote from: opnly bafld on 27 Sep 2015, 09:13 pm

Is the ZDAC set to fixed output or variable?

Did you check this?
Switched to fixed would be better, but if it is set to variable is the v/c all the way up?

JLM · « **Reply #18 on:** 28 Sep 2015, 11:05 am »

Input sensitivity of the Crown is rated at 1.4 volts for full output into a 4 ohm load. I've never seen input sensitivity for an amp rated for a given output impedance. Would sensitivity go up as output impedance goes up? What's the nominal impedance of your speakers?

What connectors are you using for input/output? I've heard that the speakon connectors are vastly superior.

Also it has various crossover modes, you're not in "Low-pass" mode are you (and only hearing bleed through)? The rated crosstalk values (why 2?) seem quite low (85 dB, 55 dB) but it's not specified as to what mode it's being applied to.

Have you called the factory for technical assistance?

I highly unlike small/multifunction display/controls like these.

sugbob21 · « **Reply #19 on:** 28 Sep 2015, 11:34 am »

ZDAC is set to variable but it is on max. The instructions on the Crown said it comes set to default mode which is apparently the normal mode to use. I haven't touched anything on the Crown but the volume. I am using RCA inputs and my regular speaker wire with banana plugs. My main issue was that with the variable inputs already on max and the volume knob up to three quarters and the Crown on three quarters I am being told that my drivers should have blown up . Yet I am 6 feet from the speakers and the volume is loud but not above the area where I cant converse with anyone.