Adding a Power AMP to a Denon AVR 3805

[lanman]

I am in the market for a used power AMP to run on my Denon 3805. The main reason for adding am AMP is the Denon lacks power in the bass area and does not really sound too good on 2 channel audio, although very nice in 5.1 mode. I like listening to audio and don’t care for the weak sound, hence the AMP. My feelings are the AMPs should match on the Front and Center channels to stay with a tonally correct sound. The other side of me says get a nice two channel AMP, since most multi-channel AMP (3 or more) don’t sound as sweet as a 2 channel one. I have been looking at some Adcom AMPS on e-bay (5 channel Adcom GFA 7000 and 2 channel GFA 5500) for around $400.00, which is around my limit. Maybe, I can squeeze $500.00. Does anyone have any experience with adding an AMP and any recommendations would be greatly appreciated as to which way I should go? What are your thoughts on the Adcom way too?

 

[Swerd]

For a used amp, you will much more likely find a good 2 channel amp than 3 channels at that price. I really wouldn't worry about any difference in the sound between amps when using multi-channel.

The Denon 3805 is a pretty decent receiver, including its amp section. You didn't mention what speakers you are driving. Do they have low sensitivity or low impedance? I wonder if inadequate amp power is the reason you are not getting enough bass.

I now use an older Denon AVR-1800 receiver (75 wpc) and have added a used 2-channel amp to drive the two front speakers. The amp is a B&K EX4420 (200 wpc at 8 ohms) that I found on AudiogoN for $400 about a year ago. This works fine in my setup. The receiver drives only the center and the two rear channel speakers and because it is relieved of driving all 5 channels, it has an easier job. Note that I run my center and rear speakers small - they get audio at 80 Hz and higher.

Adcom amps are good. I would also look for used B&K, Haffler (DH-220 or XL-280 models), NAD, Parasound, and Rotels. These should be in your price range, and usually sell faster on AudiogoN than the higher priced amps.

If you want to buy new amps, there is always the Behringer A500, a 2-channel amp at about $200. For more $, I would also look at the excellent Audio by Van Alstine amps. AVA does sell a 3-channel amp the OmegaStar 240/3EX for $1100. I wouldn't pay any higher price for an amp than what AVA charges.

 

[mtrycrafts]

I am in the market for a used power AMP to run on my Denon 3805. The main reason for adding am AMP is the Denon lacks power in the bass area and does not really sound too good on 2 channel audio, although very nice in 5.1 mode. I like listening to audio and don’t care for the weak sound, hence the AMP. My feelings are the AMPs should match on the Front and Center channels to stay with a tonally correct sound. The other side of me says get a nice two channel AMP, since most multi-channel AMP (3 or more) don’t sound as sweet as a 2 channel one. I have been looking at some Adcom AMPS on e-bay (5 channel Adcom GFA 7000 and 2 channel GFA 5500) for around $400.00, which is around my limit. Maybe, I can squeeze $500.00. Does anyone have any experience with adding an AMP and any recommendations would be greatly appreciated as to which way I should go? What are your thoughts on the Adcom way too?

I think you may have some misconceptions here about amps, power, etc.

As swerd indicated, knowing your speakers may shed some light on your dissatisfaction. Maybe they are just not capable of delivering the low frequency at the output level you would like? Maybe you just need a good subwoofer to solve that issue?
That Denon is rated from 20Hz to 20kHz, so, it will deliver the rated power at 20Hz as well as at 4kHz and is more indication that your speaker is just not capable.
How loud do you listen?

No reason why a multi channel amp will not sound the same as a monoblock or 2ch amp. And, they don't have a 'tonally correct' sound.

 

[lanman]

I know it's the Denon since I had a NAK RE2 receiver before going with the Denon and it had much punchier and sounded very tight. My system is composed of:

Denon 3805 Receiver
Def Tech BP 10s (older silk screen tweeter version)
Def Tech CLR1000 Center & Def Tech Ceiling mounts for the rear with multi direction tweeters
SVS PC PLUS Subwoofer

So, you think different amps on HT aren’t going to be a problem? I like the idea of having a nice 2 channel audio AMP.

I thank you for your recommendations and keep you posted on how this works out.

 

[PENG]

I am in the market for a used power AMP to run on my Denon 3805. The main reason for adding am AMP is the Denon lacks power in the bass area and does not really sound too good on 2 channel audio, although very nice in 5.1 mode. I like listening to audio and don’t care for the weak sound, hence the AMP. My feelings are the AMPs should match on the Front and Center channels to stay with a tonally correct sound. The other side of me says get a nice two channel AMP, since most multi-channel AMP (3 or more) don’t sound as sweet as a 2 channel one. I have been looking at some Adcom AMPS on e-bay (5 channel Adcom GFA 7000 and 2 channel GFA 5500) for around $400.00, which is around my limit. Maybe, I can squeeze $500.00. Does anyone have any experience with adding an AMP and any recommendations would be greatly appreciated as to which way I should go? What are your thoughts on the Adcom way too?

My 3805 is currently hooked up to an Adcom GFA555 (200WX2). I tried it with a 300WX2 before but to me there was no obvious audible difference. After adding the amp(s) for a while I did try removing it and I no longer noticed the initially perceived difference. My initial impression was probably due largely to the fact that I was listening hard for the anticipated improvement. At that time I took some voltage and current measurements when playing the Denon and Denon+amp at reasonably high SPL levels of up to 105 dB using my Denon 3910 universal player and bass heavy classical CDs. I found that the Denon, Adcom, and Bryston amp delivered almost exactly the same current and voltage during the loud bass drum hits or canon fires (1812 Overture). The bass sounded the same in each case, with no audible distortion. My speakers are Veritas 2.3i, with anechoic sensitivity of 87 dB/m/W and impedance of 8 ohms nominal, and 4 ohms minimum.

Your speakers may in fact benefit from a more powerful separate amp, but the 3805 does have some decent amps in it. Needless to say, if your speakers are hard to drive and are located in a large room then a 200WPC amp is going to do much better than that 120WPC Denon receiver, unless you play your system at relatively low SPL.

One last point, you did try playing your favourite bass heavy CDs in pure direct mode right? If not, you should, just to make sure the deficiency in bass is not due to the numerous settings in the 3805.

 

[lanman]

Well, this is all good stuff, especially regarding the GFA 555 hookup by Peng.
Peng, as stated, I have no issue with 5.1, so did you not hear much difference in 2 channel audio when removing the GFA 555? And yes, I have a big room which is going to dilute the sound.....unfortunately!

Swerd, I still have an 1804, and didn't realize you could pre-out the front channels. Maybe, if I had known that I could have just added the amp to it, and not purchased the 3805, although having the extra watts the 3805 has does help with center and rear channels I suppose.

Whilst thinking about this, it may be my Sony DVD player (DVP-C660) that may also be adding to this issue. I mean to say; when I auditioned CD players many years ago I found the more expensive units had a much tighter bass and better sound than a run-of-the-mill $100 unit. The cheaper analog to digital processors were not that good. I though by 2004 that had all changed.

I'll play around and see what happens. I could always audition an AMP from and see if this is the direction I should take.

 

[PENG]

Well, this is all good stuff, especially regarding the GFA 555 hookup by Peng.
Peng, as stated, I have no issue with 5.1, so did you not hear much difference in 2 channel audio when removing the GFA 555? And yes, I have a big room which is going to dilute the sound.....unfortunately!

I thought I did in the beginning, but by now I have to admit, the difference is hardly noticeable. In my 13X20 room I cannot push the Denon (on its own) in two channel to a level loud enough to result in audible distortion without risking hearing damage. If you want to be sure, find a store that allows you to do an AB comparison between a receiver and a receiver plus an amp that is within your budget.

Again, in my case, now that I have tried two different power amps, next time I would probably try out a high quality but low power amp. May be something like a 25WX2 class A Lexicon. More power of the same quality will no doubt be better but the price will be prohibitive. If I remember correctly a 25W Lexicon costs $4K, way too much already; hence it will remain in my dream for a long time if not forever.

 

[lanman]

Now you have me thinking the amp may or may not be the answer. On the subjects of amps, many years ago I had the Adcom GFA5500, PS Audio and another I cannot remember at my house for audition. Let me tell you, they all sounded completely different, as much as speakers from other manufacture do.
The Adcom was more focused by the PS Audio point of view, forward and punchy. The PS Audio was laid back and has an incredible stage presence..so smooth!
So that is why I mentioned having a matching 3 x amps on the front, although now understand this is not necessary in HT. See, I'm learning from you guys!!

 

[mtrycrafts]

Whilst thinking about this, it may be my Sony DVD player (DVP-C660) that may also be adding to this issue. I mean to say; when I auditioned CD players many years ago I found the more expensive units had a much tighter bass and better sound than a run-of-the-mill $100 unit. The cheaper analog to digital processors were not that good. I though by 2004 that had all changed.

I'll play around and see what happens. I could always audition an AMP from and see if this is the direction I should take.

No, your Sony player is not the issue either, especially if the digital out is used. I doubt you have a real issue, just expectation biases and perception issues that can be misleading.

I bet your CD audition was not bias controlled, levels matched. CD players with flat frequency response that I am very sure that Sony has, will not cause tighter bass or anything like that.

Actually, Axiom just sent out their usual newsletter in which they discuss the low band, sub caused, being 'tight' or 'flabby' as some reviewers call it. All nonsense. Audio is full of urban legends, voodoo, and misconceptions; be careful.

The $ensible Sound did a DBT of an RCA carousel CD player, $80, compared to ones costing $1000s. Not one of the panel could differentiate between them under bias controlled conditions.

 

[mtrycrafts]

The Adcom was more focused by the PS Audio point of view, forward and punchy. The PS Audio was laid back and has an incredible stage presence..so smooth!
QUOTE]

I bet you that if you carefully level matched them, hid the identity, that is double blind(bias controlled) you would not be able to tell a difference int hat your guesses will be not statistically significant. Other DBTs over the past 25+ years is not in your favor for audible differences, unless one was broken or driven beyond its design limits. Sorry.

 

[Swerd]

... On the subjects of amps, many years ago I had the Adcom GFA5500, PS Audio and another I cannot remember at my house for audition. Let me tell you, they all sounded completely different, as much as speakers from other manufacture do. The Adcom was more focused by the PS Audio point of view, forward and punchy. The PS Audio was laid back and has an incredible stage presence..so smooth! So that is why I mentioned having a matching 3 x amps on the front, although now understand this is not necessary in HT. See, I'm learning from you guys!!

The subject of whether amps have a recognizable sound of their own is often debated. I don't really want to continue that debate here, and I certainly don't want to cast doubt on your past experience that you described. My own experience is that I can't hear any differences in solid state amps when they are not clipping. In fact, I can't tell when there are small amounts of clipping without a clipping indicator. I also have not heard any difference between a class A or a class AB amp.

I can hear the difference in amps (with the speakers I own) when one amp is at least 3 times more powerful than the other. The improvement is more subtle than differences between speakers that I have heard. It is hard to describe in words, but better sounding bass and more dynamic response overall comes to mind.

I make this sound like I have systematically examined all this. Not so. I have listened to many, many different speakers (especially DIY speakers), but comparing different amps is rather like listening to different brands of paint dry. I have been exposed to several very good DIY speaker designers who all share the opinion that amps don't matter very much, as long as they are powerful enough to avoid clipping. I have certainly been influenced by those opinions. While I'm on this subject of opinions about amps, I have also heard from at least two people who understand the electronics behind amplifier design, that they prefer solid state amps that use MOSFET output devices. I can't repeat all the reasons why they say this, but I do respect these opinions.

That is the long reason why I suggested those moderately priced used amps. They will get they job done without clipping.

 

[lanman]

I think most amps are very similar in sound, almost unnoticeable differences (solid state) except for power handling. There are a few though, as I described that sounded very different. Point in case; many years ago whilst in an audio stores I was auditioning integrated amps. These were using the same source and speakers, being swapped out after each hearing test. Rock music on one sounded so boring and clinical, the other incredible…alive!! I’ve heard this difference with a few AMPS being used on the same pre-amp, source and speakers. Don’t ask me what causes this, mismatch of pre-amp vs. amp, I have no clue. I have personally heard differences. Some just sounded plain boring or not what I call right for me. Another, I fell in love with the music again. That’s what my ears heard…. nothing more, nothing less!!
So, I’m not saying this is always the case and certainly don’t want to start a 100 part thread on the subject either. Just my experience.


I do thank everyone for their input on my thread and wish you all a very happy holiday!

 

[mtrycrafts]

... Point in case; many years ago whilst in an audio stores I was auditioning integrated amps. These were using the same source and speakers, being swapped out after each hearing test. !

Well, here is a famous test between an integrated Yam, about $300 and monoblocks costing $15k, Pass Aleph with 3 'golden ears.'

http://groups.google.com/group/rec.audio.opinion/browse_frm/thread/664b8681ab141263/3fd91bcb6a1522a0?hl=en&lr=&ie=UTF-8&oe=UTF-8&rnum=1&prev=/groups?q=sunshine+stereo+yamaha+abx+nousaine&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=501fl6%24ac3%40oxy.rust.net&rnum=1#3fd91bcb6a1522a0

AND a number of others, in Spain, but the Google translator will help

http://www.matrixhifi.com/pruebasciegas.htm

 

[lanman]

Mtrycrafts: I totally agree with the thread you sent me regarding the Yam and $15K amp listening tests, but need to qualify my answer, which is:

If you A + B amps together in quick succession there are differences…that I know. But, if you take someone out of the room, have a cup of coffee and send them back in and play a track of music on one particular amp and have them guess which it is, I agree this is very difficult to do, since you lost you reference point between what ever equipment you were comparing. A subtle difference in A+B testing can be totally lost as time goes by and there isn’t that comparison. So, this brings up a discussion, which I was guilty of, and referenced in this article too, is not to try and make your self go totally mad trying to pick the better piece of equipment. Leave it long enough and it all sounds ok!!

Also, if there are no differences in amps, why do professional writers, when comparing two amps side by side, mention one may have a harsh mid range, the other much better and tighter bass – all this going through the same pre-amp.

Same can be said of the infamous NAD 3020, which annihilated the competition and became an overnight success due to its sound.

I wonder if you removed someone’s Krell amp and replaced it a $300 Yamaha and they come back from a week’s vacation, if they would notice. I wouldn’t like to say no, and yet I wouldn’t go with yes either.

Back to the original thread of adding an amp to the Denon 3805. I have played with dialing this receiver in and at the moment like the way it sounds, especially on 5.1.

Definitely, a little better sounding than my1804, but from what I have read the 4800 series is a major jump, anyone want to comment on whether or not to add an amp to the Denon 3805 or buy the 4806. Or, have we had our day on this thread?

 

[PENG]

anyone want to comment on whether or not to add an amp to the Denon 3805 or buy the 4806. Or, have we had our day on this thread?

Some people like to insist on getting the same power for all 7 channels. I have no problem seeing the benefits of doing so but if someone sets a limit on how much to spend, say $2,100, then consider the following logic.

Assume a typical mid level amp costs $1 per 0.5W, $2,100 will get you 150 WPC for a 7 channel amp.

Now if you were to spend that $2,100 on a 3 channel amp, you would get 150X7/3=350WPC, or on a 2 channel amp, 525WPC. Alternatively, you can get a higher quality 2/3 channel amp vs a lower quality 7 channel amp of similar WPC. Either way, it is about investing on areas that offer the most reward.

So I would say if you want to get the best out of your BP10 playing 2 channel music, get a high quality/power amp for now and you can always pick up another 3 or 5 channel amp in the future. If you are more concern about multichannel stuff then get a 7 channel amp. Just keep in mind that for a given budget, getting a 7 channel amp will mean less power for the front BP10's. I do not recommend upgrading to the 4806 because it costs much more than the 3805 but does not offer significantly more power.

 

[Warpdrv]

I agree... with your main concern being 2 channel audio... a good 2 channel amp would be a great addition.. and as you already know, your BP10's have a nominal impedance of 6 ohms, so if you get a 200x2 amp, it will more then likely pump out between 250-300wpc to your BP10's

Although I would go for a 5 channel amp for my system, I find huge amounts of power for surrounds not nearly as important then the front sound stage...

I would venture to say a good 2 channel amp would serve your purposes quite well... letting the Denon taking care of the duties running the smaller center and ceiling speakers.

 

[Bluesmoke]

Get yourself a Behringer A500 amp. Torroidial transformer. Convection cooling (ie, no fan) and just sounds great. 150w@8 ohm stereo. Would be THX Ultra certified probably if they wanted to.

 

[mtrycrafts]

Mtrycrafts: I totally agree with the thread you sent me regarding the Yam and $15K amp listening tests, but need to qualify my answer, which is:

If you A + B amps together in quick succession there are differences…that I know.

You know this because why? YOU have conducted such tests, under DBT

protocols? Levels matched?

But, if you take someone out of the room, have a cup of coffee and send them back in and play a track of music on one particular amp and have them guess which it is, I agree this is very difficult to do, since you lost you reference point between what ever equipment you were comparing.

Is that what was done in that Florida DBT? Or didn't they use an ABX box and none of the 3 could differentiate under the ideal condition?

No, you are grasping at straws here

A subtle difference in A+B testing can be totally lost as time goes by and there isn’t that comparison.

Yes, it can but was not the case in that link, was it?

Also, if there are no differences in amps, why do professional writers, when comparing two amps side by side, mention one may have a harsh mid range, the other much better and tighter bass – all this going through the same pre-amp.

Oh, please, not the pro reviews Which ones were you referring to? The ones in Stereophile? TAS? Which one? Can you point to one that used DBT protocol, levels matched and statistically significant results? Or they just used the sighted comparisons, no rapid switching as you brought forth above, and waxed eloquently having ZERO value. No, they are just BSing, selling, period, end of story.

Same can be said of the infamous NAD 3020, which annihilated the competition and became an overnight success due to its sound.

Oh, really? Where, when? How was this established?

I wonder if you removed someone’s Krell amp and replaced it a $300 Yamaha and they come back from a week’s vacation, if they would notice. I wouldn’t like to say no, and yet I wouldn’t go with yes either.

What kind of comparison is that?

 

[pbarach1]

Why don't you set the Denon to use the subwoofer in 2-channel audio; then you should have plenty of power without having to buy a separate amp, since the SVS's amplifier will be doing the heavy lifting in the bass, where most of the power would be needed.

 

[davidtwotrees]

I just love it when a new subjectivist pops up!