TacT S2150 vs Blue Circle 204 amp comparison

ekovalsky · « **on:** 12 Aug 2005, 08:32 pm »

Tomorrow I am picking up a BC204 stereo amp from Marc Mickelson of SoundStage. It will be used to drive the main channels of the Alon speakers via the DAC output of the TacT RCS 2.2X, which is fitted with the Aberdeen Signature power supply.

This will allow a direct comparison with the TacT S2150 amp. Both the S2150 and BC204 are 150 watts per channel into 8 ohms, so there should be no advantage of either amp in terms of power delivery (the speakers are a nearly resistive 8 ohm load). So the only variables will be the amplifiers themselves, the DAC card (used with the BC204), and the interconnects (XLR from RCS to BC204, AES/EBU from RCS to S2150).

Since I only have one DAC card, the sub towers will have to be driven by my other S2150 amp. The Crown is better suited for that role but the TacT amp handles them quite well given their 2 ohm nominal impedance. While I have the S2150 driving the subs, I'll take some measurements with the correction filter implemented within the S2150 -- it's pretty cool to see in-room bass measure perfectly flat! For shits and giggles, I'll also turn the microphone 90 degrees, making the L sub front and the R sub rear, and take a measurement with the "rear" sub delayed and reversed polarity, and without delay with normal and reverse polarity.

Given the differential in cost, size, and weight between the BC and TacT amps, the S2150 is the clear underdog heading into this comparison. With any luck I will also be receiving a hot-rodded S2150 from Anthony at Aberdeen while the BC204 is still on hand -- maybe the madman from Las Vegas will be able to even the odds

More to follow...

Thanks to Bingenito and Gilbert Yeung for this opportunity. Also to Marc for meeting me half way to make the exchange.

zybar · « **Reply #1 on:** 12 Aug 2005, 09:51 pm »

Should be very interesting and I look forward to your thoughts.

I recently did the same thing when I had in a pair of S2150's to compare against the reigning champ - McCormack DNA-500.

Let's just say it was a knockout by the champ and the S2150's are on longer here.

George

Bingenito · « **Reply #2 on:** 13 Aug 2005, 03:29 am »

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Thanks to Bingenito and Gilbert Yeung for this opportunity. Also to Marc for meeting me half way to make the exchange.

You’re welcome! I look forward to your comments.

On another note...Looks like you transitioned from the Tai Chi pill to the “slightly” darker avatar

ekovalsky · « **Reply #3 on:** 14 Aug 2005, 04:59 pm »

After a few hours and some re-tweaking the TacT....

For starters, the TacT S2150 is vastly better on the subs, and in fact the BC can't really drive them at all -- not unexpected since they are a 2 ohm load. I only tried to used the BC204 on the subs to get a comparative time measurement. Elapsed time from input to output is about 2.35 msec faster through the BC204 than the S2150.

At first something wasn't quite right with the S2150 on the mains. After realizing that the BC unconventionally has pin3 non-inverting on its XLR input, I inverted polarity to the RCS main outputs. Now the BC204 is kicking some serious ass in the mids and highs. Bass on the mains is great too.

The BC204 is an incredibly good amplifier! Absolutely no graininess driving 18 ribbon tweeters and silky smooth across the entire frequency range with the main towers' 8 ohm impedance.

ekovalsky · « **Reply #4 on:** 15 Aug 2005, 06:06 am »

Turns out that the TacT S2150 doesn't drive the subs too well either. Compared with the Crown K2, there is significant SPL drop off below 30hz. I guess the S2150 doesn't like it below 2 ohms -- the subs dip to 1 ohm at 19hz.

The K2 is hard to beat as a subwoofer amp!

Bingenito · « **Reply #5 on:** 15 Aug 2005, 10:32 am »

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The K2 is hard to beat as a subwoofer amp!

I would have to agree there. The K series amps are designed to drive subs. Even with a 2 ohm load the dampening factor is still 750 which is better then most amps driving an 8 ohm load.

I will not comment on the BC204 since my comments could be considered biased

PhilNYC · « **Reply #6 on:** 31 Aug 2005, 04:15 pm »

If I can make one suggestion that might be of interest to you...if the RCS 2.2x has a single-ended/RCA analog output, try running that into the BC204. The single-ended and balanced inputs on the BC204 have a slightly different sound based on the design of the input stage.

Bingenito · « **Reply #7 on:** 31 Aug 2005, 04:21 pm »

The 204 was shipped back on Monday to the next review. Good suggestion!

JoshK · « **Reply #8 on:** 31 Aug 2005, 04:25 pm »

I got to hear the 202 *I think* (phil correct me if I am wrong here) at the Rave at my place for a bit. Others noted it too, but this is probably the best sounding amp I've heard to date in my system.

PhilNYC · « **Reply #9 on:** 31 Aug 2005, 04:27 pm »

Josh...yes, that was the BC202 (120wpc version of the BC204)...thanks!

zybar · « **Reply #10 on:** 31 Aug 2005, 04:33 pm »

Quote from: ekovalsky

Turns out that the TacT S2150 doesn't drive the subs too well either. Compared with the Crown K2, there is significant SPL drop off below 30hz. I guess the S2150 doesn't like it below 2 ohms -- the subs dip to 1 ohm at 19hz.

The K2 is hard to beat as a subwoofer amp!

AGREED!

I loved the K2 driving a pair of VMPS Larger subs. I sold the subs, but kept the amp for when I get my next subs.

George