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Tube power to drive sequel II

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cyclone

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I am contemplating changing to a tube amp to run my Sequel IIs I am currently running a ARC D400 at 200 watts per. My question is what type of changes in sound should I expect from the change and how much power would be the minimum I need? (I like my listening on the loud side) My short list so far includes ARC VT100 MKII & ARC VT200. Oh by the way I run two Velodyne FX12 subs in my system.
 

roberto

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cyclone said:
I am contemplating changing to a tube amp to run my Sequel IIs I am currently running a ARC D400 at 200 watts per. My question is what type of changes in sound should I expect from the change and how much power would be the minimum I need? (I like my listening on the loud side) My short list so far includes ARC VT100 MKII & ARC VT200. Oh by the way I run two Velodyne FX12 subs in my system.
Hola. My liking is for the ARC VT100MKII. It has enough power to drive any ML model with outstanding results. You should expect warm, calid, right timbre, lay back stage, very 3 dimensional sound and right size of the instruments. Voices are one the best too. Happy listening,
Roberto.
 

twich54

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Check out aliveatfive's ad, he's stepping up to the new ref stereo unit and his Vt100mkIII is listed in the classifieds !
 

Statman

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I have to agree with Roberto on the three dimensional aspect using a tube amp. In my system back in the 90's I ran my Sequel II's (when they were my front channel speakers) thru an ARC SP-14 and Classic 120 monoblocks. I was so impressed with the imaging that that combo did. ;)
 

Spike

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cyclone said:
I am contemplating changing to a tube amp to run my Sequel IIs I am currently running a ARC D400 at 200 watts per. My question is what type of changes in sound should I expect from the change and how much power would be the minimum I need? (I like my listening on the loud side) My short list so far includes ARC VT100 MKII & ARC VT200. Oh by the way I run two Velodyne FX12 subs in my system.
Given that you have a preference on the loud side, I'd keep the D400 for the bass and get the VT100 for the panels. One of the drawbacks that kept me from ARC tube gear is the requirement for 4 matched-pairs of 6550C, resulting in expensive retubing cost. Are there any reasons for the ARC-only short list of VT100 and VT200? What is it that you're looking for going from the D400 to tubes?

Spike
 

cyclone

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I am using a Wadia 861 direct into the D400 now and the resolution and detail (also fantastically tight bass) is just amazing but I lost the midrange warmth I had with it running thru my ARC LS5 MKIII preamp (which in my opinion is a fantastic pre) I was hoping by going tube amp I could get the best of both worlds.
In Biamping how do you cable both amps from the source and how do you keep the output level even?
 
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Spike

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I went to take a look at some datasheets and here's what I can come up with for your Wadia 861 and the ARC amplifiers in bi-amp configuration...
The Wadia has both balanced and single-ended (RCA) connector on the back which can be used simultaneously. The ARC VT100 has balanced inputs and I recommend to use the balanced connections between the Wadia and the VT100. The connection between the Wadia and D400 will be via the single-ended (RCA) connectors. Given that both ARC amplifiers spec'ed input sensitivity to be 1.9V RMS to drive to full output, they should be quite close in the gain that you might not need to attenuate the bass on the more powerful D400. If you find that you do need to attenuate the bass for some reason, I think the Sequel II has a bass attenuation knob on the back (like my ReQuests) that you can tune the bass down a bit. If you do need -3db attenuation (the gain difference between D400 and VT100), here's a list of In-line attenuators from Parts Express to go at the input of the D400. I think the 3db attenuators are good enough for this case if needed. Good luck

Spike
 

cyclone

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I'm already using the rca outs on the 861 for my subs.
 

Spike

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Statman said:
The Sequel II's do not have an attenuation knob. :(
In-line stepped attenuation is what you'll need. Check out these stepped attenuators from Endler Audio to be installed at the input connector(s) of the bass amplifier.

cyclone said:
I'm already using the rca outs on the 861 for my subs.
You can split the RCA signal using this splitter from Monster Cable


Good Luck
Spike
 

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