Digital amps on ESLs

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JordanD

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Afternoon all,

I was just curious on getting input from everyone on using digital amps to power my Theos.

For those who don't know I am using an Marantz SR7005 to run my system, and in the small space I live it doesn't do half bad. It actually performs rather well, but I always feel like I have a racecar running on the incorrect fuel. Like they want to open up they just cant.

I always had plans of upgrading, but being a college student most of my funds go into school and food, and what I can scrounge goes into my toys.

A friend of mine just picked up a pair of Bel Canto's 500 watt monoblocks for his Vienna Acoustic Mozarts and they are really impressive little amps in a price range I can probably pull off sooner rather then later. I also know that there are a variety of companies out there who are building similar products all in a similar price range.

My question is: does anyone have experience on this subject? And can you elaborate on those experiences?

I was planning on using the 7005 as a preamp initially until I can get all my amps in place then probably upgrade that as well.

Any input?
 
Hola Jordan, I have several customers that are using their digital amps with ML with no problem. Brands like Bel Canto and ARC. But it is your call. Remember that the stat panels are like a big capacitor, not an inductor or a resistor. So the amp is going to drive a capacitive load. To me, I do like tubes a lot, and I think they shine with Martin Logan. I had for over 2 months an Audio Research HD-220. It is a very nice, power full amplifier, it is a hybrid, tubes at the first stage, and SS at the final...all I can say is that I am back with my old beloved ARC VT-100MKII modified at the power supply and also using KT-120 tubes at final. I do like a lot what I am listening! Happy listening.
 
I run Bel Canto Ref500m amps with my Vantages with no issues, and they sound great!
 
I have been running a QSC 1804 on Martin Logan Monolith III's for 5 years now...no problem. Need a good source though.
 
I've had fabulous results running a pair of Jeff Rowland 201 amps into my Summits. I'm preparing for building a new house and a planning a big Prepro purchase in 2015. Therefore I'm making due just fine with Sony 808ES receiver connected via RCA. Family and friends rave about system now so can't wait to introduce PrePro and Audioquest Cheetah XLR cables now in box. Rowland's have warm and welcoming robust sound- fabulous soundstage.
 
Thanks for the feed back everyone! I was thinking there shouldn't be any issues, but I just wasn't sure if there were any odd factors to consider.
 
Topping TP60 class T amp

Hi Jordan,
Since you're a student and have limited budget, I would like to also suggest the Topping TP60 amp(s). There're a lot of small t-amps out there but this one is best in term of power, sound quality, and build quality (look at the internal construction pictures). If you dont listen to your music at an insane level, I highly recommend it. You can find a lot of reviews on the good sound quality of t-amps and this one has the sweet, smooth sound of tube. It's only a bit over $200 on Amazon. It's easy, no hassle to return if you dont like it.

If you decide to buy this, I would suggest you buy 2 of them to biamp your Theos, one amp per channel, to have higher power/more headroom and better sound quality. Total is just about $420 for two amps. Also, allow a lot of burn in time for them (100-200 hours). Dont rush and judge them right away. They might sound just a little edgy on the top end at the beginning but smooth out around 50 hours. Bass and mid range would also improve at about 50 hours.

You should seriously consider this little guy and give it a try. Dont let the low price and small size fool you. I tried it before with my Vista speakers and I was impressed.

Part Express has the completed/most info about the amp but the price is more expensive then Amazon. http://www.parts-express.com/pe/showdetl.cfm?partnumber=310-326

Good luck.
 
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Wow Dan thanks! That is the kind of info I was looking for. I was a little hesitant about them at first but after reading for a while they seem pretty solid. And even if they don't work out I wont feel bad because the initial investment is small enough. My space is small (about 15' x 15') so I don't think the low power on them should matter all that much, but then again my Marantz is rated at a higher power then these. Would I even be making an improvement? I realize that by making the amps out-board then the sound stage should become much better... I'm not sure.

Thoughts?
 
If you're looking for a higher power amp to replace your Marantz or want to play louder, the TP60 is not the one. It will not sound any louder than the Marantz; maybe even not as loud if you go with 1 amp. That's why I recommend buying 2 amps to have a similar power output and more headroom. But high power doesn't mean better sound quality. I have two Emotiva UPA-1 mono blocks (200W/channel) and they dont sound as nice as the TP60.

However, I'm pretty sure that you will have an upgrade in sound quality (compared to the Marantz internal amp section) from separated amps, high quality parts, dedicated power supply (with dual power transformers/amp) and the nice sound characteristics of a tripath chip. You will probably hear better channel separation, instrument separation, more details, better transparency, and a larger sound stage.

So again, I suggest you order 2 from Amazon, burn them in for 2 weeks straight, then listen to them/compare to your Marantz for a week. If you dont like them or hear no differences, you still have a week left to file a return. I dont own a Marantz receiver so I can't say how much better you would get but I can say the TP60 sounds better than my Onkyo TX-NR906 receiver (top of the line Onkyo receiver from 4-5 years ago). Also try them w/o the Marantz as preamp since they have built in volume control to see how they sound. I guess they'd sound better w/o the Marantz in the mix.:)
 
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I am probably just going to pick up a pair soon and play around with them, but I will be using the Marantz as preamp. I kind of have to. Well I guess I don't but it will just be much easier if I do. Oh and I love the sound of my Marantz, there is nothing wrong with it, but I always wanted to give the speakers better power if that makes sense.
 
I would be cautious with digital amps since they tend not to have linear high frequency response. Their frequency response seems to be very dependent on the speaker load and, since speakers differ, so does the frequency response. You also might have some issues with RFI and ultrasonic noise since they also seem to be emitted in abundance with switch mode amps.
 
Just my 2 cents coming late into the thread. I've been pretty happy with my Rotel 1560 AVR with a Class D amp section. It's rated at 100 wpc into 8 ohms and 200 wpc into 4 ohms. It dirves them quite well and I've been pleased with the sound. I was leery when I first purchased it so I also got their 250 wpc (500 in 4 ohms) stereo amp. When I moved, I was too busy (lazy) to hook it and ran just the AVR. I was so happy with the AVR alone (didnt hear any difference) that I sold the external Rotel amp.
You could probably pick up a Rotel RB-1572 pretty cheap now.
 
Yeah I was really considering Rotel. They get great reviews and their price point seems very reasonable.

@pneumonic: Can you explain what your post mean a little more in depth. If it helps I have ML Theos and that is what I am going to drive.
 
My Rotel Class D gear has been very stable with no signs of overheating, clipping or shutting down. The power output doubles when you go to 4 ohms. I think @pneumonic is concerned with the cheaper Class D stuff which may not be able to handle the loads that the ML's demand and will distort or shut down. You need something that is stable at least down to 4 ohms no matter what type of amplifier you're looking at.
BTW.. Nice setup you have!

Yeah I was really considering Rotel. They get great reviews and their price point seems very reasonable.

@pneumonic: Can you explain what your post mean a little more in depth. If it helps I have ML Theos and that is what I am going to drive.
 
Oh okay, I see. The Rotel use the B&O ICE amps so they are known to be one of the better D-class amps, so I think the choice in them is a good one.

Oh thank you! haha
 
Hey Jordan,
Another suggestion, if the Topping TP60 or whatever amp you're getting wont work out. Emotiva just came out with a new monoblock, XPA-1L, that is pure class A (up to 35W), fully balanced at $699. Above 35W or if the amp runs too hot, it switches to class AB and can handle up to 200W or there's switch in the back to always run in class AB mode. Very interesting amp for the money. 30 days money back and 5 years transferable warranty. It doesn't hurt (much) trying :)
 
Yeah I am aware of the emotiva gear and I have quite a bit of personal experience with their gear. Great stuff, I am just looking for something else. I am just trying to try something different hence the digital amps I am looking at.
 
When I got my ML'S I was ready to get rid of the Bel Cantos but soon realized they were full well up to the job with no issues.
 
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