JVC F10 help needed - Where is the bass??

JohnnyLightOn · « **on:** 9 Mar 2005, 11:41 pm »

I'm very happy with my F10 so far, except for one thing: the bass is just not there like I want.

Some background and system specs:

Speakers are 90db, 4 ohm, 2.5 way, B&W Matrix 3 Series 2.
Speaker wire is (currently) long, uneven runs of old m*nster cable.
Source is a Squeezebox (transport) into an Ack dAck 2.0.
Interconnect is Cardas 300B-Micro.

The F10 replaced an 18-year-old Yamaha A-1000 120w SS amp. That Yamaha had tons of bass---too much, really. It had gobs of warm, bloated, loose bass. I hesitated turning it up so my apartment neighbors wouldn't be be disturbed.

The F10 gives me great midrange and airy, detailed highs, but its bass is so weak I find myself turning it up just to get some bass going. On rock recordings, the bass is definitely audible, it sounds accurate, but there's a viscerality missing from it. I can't feel the thump that I know my speakers are capable of generating. I played a symphony last night, and all the sweetness and detail of the smaller strings came through, but there were no warm, palpable, resonant bigger strings. The general sound signature is the same when I use the tuner, so I don't think it's my source.

I'm really puzzled because I have heard nothing but good things from others running this amp into 4 ohm speakers, and almost no one has complained about the F10's bass. Furthermore, nothing changed between the Yamaha amp and the F10, except that with the F10 I've had to twist the large-gauge stranded speaker cable into a tiny little cone to stick into the speaker clips. But I was still able to stuff a good piece of cable in there. The speaker cable is about 20' long.

Do you think it could be my speaker cable? I'm going to be receiving some 12ga magnet wire soon that I'll try in much shorter lengths. Or is the F10 just the wrong amp for my speakers? I really like my speakers and the other things about the F10 (not the least of which is price), and hope to find a solution to this.

Thanks for any assistance!

TheChairGuy · « **Reply #1 on:** 9 Mar 2005, 11:50 pm »

No noted bass deficiency on any of three speakers I tried it on.

CAT6 14.5 guage cable is what I use - 6' pair of bare wire.

Separation of everything, including bass, gets a lot better with great power conditioning. Can't emphasize that point enough...to the point of 'ad nauseum'; there goes TheChairGuy popping off again on that bloody subject.....

JohnnyLightOn · « **Reply #2 on:** 9 Mar 2005, 11:59 pm »

Thanks, ChairGuy - I am absolutely going to condition my power and have saved your posts on the subject. But I think while it will help with many factors, I don't know if it will affect the sheer amount and weight of the bass, especially increasing it to the degree I think it's now missing.

Horizons · « **Reply #3 on:** 10 Mar 2005, 12:00 am »

I had always used a subwoofer with my Maggie 1.6QRs but when I got the F10, it was the first time that I considered not using the sub.

Bass is very tight with digital amps, not loose at all. However, the F10 has a warm tonal balance and does not lack bass IMO.

I am currently using 15 foot runs of 16Ga zip wire but I intend on trying 14GA magnet wire just for kicks. I don't believe that your speaker wire has anything to do with your percieved lack of bass.

Are you going analog in?

JohnnyLightOn · « **Reply #4 on:** 10 Mar 2005, 12:01 am »

Yes - analog in using the DVD-Multi circuit.

KCHANG · « **Reply #5 on:** 10 Mar 2005, 12:13 am »

Hi Johnny,

Your problem of weak bass from the F-10 is kind of strange. Have you tried switching back to the Yamaha receiver to see whether the bass would return?

Also, could it be that the speaker wires for the two channels are connected out of phase?

I use my F-10 in the DVD-Multi mode to bi-amp my main system that has four 18" woofers on each side, and there is no shortage of bass.

Kurt

JohnnyLightOn · « **Reply #6 on:** 10 Mar 2005, 12:30 am »

Man...I am so confused! Could I have gotten *2* defective receivers? (I returned my first one, see thread on F10 break-in).

Thanks for your thoughts everyone. I lent my old amp to someone, but will ask for it back to make sure my speakers and cables are OK. I think I will work with the speaker cables to make sure I've got a strong connection.

Kurt, I will also try the phase switch just to make sure, but I tried it both ways previously and it images correctly the way I have it.

I am open to more comments if there's anything that hasn't been covered...

TheChairGuy · « **Reply #7 on:** 10 Mar 2005, 12:34 am »

Quote from: JohnnyLightOn

I am open to more comments if there's anything that hasn't been covered...

Maybe you're just a bass whore?

JohnnyLightOn · « **Reply #8 on:** 10 Mar 2005, 12:36 am »

Believe it or not, I did consider that.

But I don't think that's the problem.

quantumfish · « **Reply #9 on:** 30 May 2005, 04:42 pm »

Hi,
i seem to have run into the same problem...

just bought a f10 and hoping it would better my t-amp in this respect I was utterly disappointed.
I went through all the settings as mine is a demo unit, but i could not find anything to reset.

bass just isn't there, a lot less than the humble 6W t-amp, the highs are nice, but even there I find that the t-amp does it better.

my spks are dynaudio audience 42s as well as audio physic virgos
both show the same problem - and are 4ohm of course.

should i just sell the f10, forget about pannys as they are even more picky, buy new speakers or just start modding my t-amp???

yours

TheChairGuy · « **Reply #10 on:** 30 May 2005, 04:58 pm »

Tough call on that one...

Change out speaker cable to something thicker on the F10 maybe?...it will reduce resistance in whatever length you have and may give you the bass
'oomph' lacking.

Other than that, the problem could just be synergy, opinion, taste, room interaction, etc. The F10 has enough bass for me - I do not notice any deficiency thereof.

Make sure yours is broken in before you proclaim it not quite right....tho less finicky than the previous generation ES-1sl in break-in, it still needs time to flesh out.

Further, I'm not sure if you are using your T-amp on battery (absolutely the best way to power it - modded or not)...but if you are using the F10 without a/c conditioning, you're not getting all out that you can from it. Notably, separation of instruments, quietness and thus, the dynamics (bass particularly) will seem restricted versus one that has good a/c conditioning on. I've had the F10 direct into the wall and it ain't nuthin' that particularly special, but thru a good conditoner and it's light years better than it's low cost would indicate.

Hope there is a nugget of help in here for you. Welcom to Audio Circle

fabaudio · « **Reply #11 on:** 30 May 2005, 05:00 pm »

Quantumfish

should i just sell the f10, forget about pannys as they are even more picky, buy new speakers or just start modding my t-amp???

Tough question!

quantumfish · « **Reply #12 on:** 31 May 2005, 09:58 am »

@chairguy

thanks for the quick reply...

my T-amp runs on a 12V7Ah rechargeable outdoor battery(SLA), I did not mod anything about it (like the input caps)... and it stills feels that the bass is more precise than the F10

I just happened to listen to my f10 after breakfast today as i still cannot believe the difference - and i must revise the statement I posted yesterday...

I think the bass is there, it is just "slow" and not precise (like the t-amp), the highs are good, very natural, really a bit tube like, but also without the "sparkle", bud that could well be caused by the inductance of my "speaker cable".
Im running both amps on 1 Strand of Cat5 wire, so both are comparably handicapped in this respect.

Break in: the f10 was a demo, as i do not know anything about it, i decided to run the full course before judging it...

Tweak: I opened the unit yesterday - and it realy crammed, so apart from the power cable there is not so much i could do, no idea where to put proper binding posts...

so, I'll keep you informed

TheChairGuy · « **Reply #13 on:** 1 Jun 2005, 03:35 am »

The SLA's offer a totally black background.....a really good ac conditioner (I love the BPT stuff myself) on the JVC will get you 90% of the there; but not the whole way.

That pitch blackness of the SLA may have more to do with trhe more solid basslines you are hearing than anything else....rather than any particular deficiency of bass with the JVC. Out of a total black background, the bassline will stand out cleanly....and more enjoyable.

I'm listening to Steel Pulse (reggae) right now - plenty of bass going on for me (w/o sub)

But, the tradeoff (right now) is limited power with the Tripath's - anathema to my Maggie MMG's

quantumfish · « **Reply #14 on:** 2 Jun 2005, 09:28 am »

still experiencing strange things...

first of all: burn in helped (20h until now) a bit. bass is definitely there by now (deep yet not very full, but that might just be the way it was supposed to be). naturalness is a really amazing, but the "sparkle" or "air" is still a bit short compared to the t-amp. otoh there are no ugly sibilants even in difficult recordings (like nora jones, diana krall) - maybe a bit of a high frequency roll of.

funny thing is, the digtal in sounded a bit better than my expensive dac/preamp route where i turned the volume up to 50 and let the preamp do the attenuation. so today i plugged the dac directly into the f10, but had no time for critical listening... (btw dacs really seemed to have improved lately, if the jvc is a lesser example and still compares quite favorably to my lehmann audio dac which is some 6 years old)

anyway, it's good fun to play with all the settings...

yours

qf

btw i just found a dvd receiver using the tripath 2020 module on ebay. seems of chinese origin, but then, a lot of things are nowadays...

I think I'll try to get it just to tell you guys about its sound....

JohnnyLightOn · « **Reply #15 on:** 2 Jun 2005, 04:19 pm »

I think the consensus among most of us is that it takes about 80 hours for the F10 to really show its stuff. Harshness leaves, and air and sweetness and detail enter. So if you're only at 20h and are getting a feel for it, give it another 60 hours and everything you like about it should really increase!

Another break-in step for the F10 is at 300 hours, although I didn't notice this myself.

JeffB · « **Reply #16 on:** 2 Jun 2005, 05:13 pm »

For a short while, I had both an F10 and an SI. They were driving some extremely cheap 4" full range drivers. The F10 had significantly more bass response than the SI. The SI was supplied with a 5AH SLA. However, although the SI had less bass in terms of volume, it did seem to have an earily accurate roll-off. It left a strange impression of the bass going down forever, just not very loud. I am inclined to think you have a defective F10. I don't think break-in is going to really give you more bass. Break-in makes the bass a little more accurate, maybe a little fuller, but it is fairly subtle. It is also possibly a system synergy problem.

quantumfish · « **Reply #17 on:** 6 Jun 2005, 04:18 pm »

To make it short,
I'll be returning the little JVC to the dealer this week. He tried to convince me to try out a new one ( as mine is a demo unit ), but I rather think that there was nothing wrong with the Receiver, maybe just a synergy problem. And it runs really hot, which i think is odd, considering the much touted effectiveness of this kind of amplifier design...

BTW i snatched the 29€ Tripath 2020 based CD receiver on ebay.
If anyone is interested, I'll keep you informed! (This is as much part of the hobby as listening itself - you are a great bunch of people, in case I haven't mentioned this before)

yours
qf

hershey 22 · « **Reply #18 on:** 7 Jun 2005, 01:12 am »

Quote from: quantumfish

To make it short,
I'll be returning the little JVC to the dealer this week. He tried to convince me to try out a new one ( as mine is a demo unit ), but I rather think that there was nothing wrong with the Receiver, maybe just a synergy problem. And it runs really hot, which i think is odd, considering the much touted effectiveness of this kind of amplifier design...

Sorry to hear it didn't work out QF. I am very perplexed when I hear about how hot the JVC runs. I play mine all day and leave it on all night and into the next day and it runs lukewarm at it's hottest. Very strange! Synergy is very important with this unit and I guess you either have it or you don't.

I do have several other problems with this unit. I still get a crackling or popping when I adjust the volume control knob. Also, I think I lost my digital input for some strange reason. I got nothing when I went back to do an A-B test the other day. I need to find out if it's the receiver or my CDP. The last thing I want to do is take this thing into the shop and have more problems when I get it back then when it went in!! Anyhow, good luck QF and I hope you find something that hits the right chord!!

quantumfish · « **Reply #19 on:** 14 Jun 2005, 08:52 am »

Sent back the JVC and got this Tripath based DVD receiver meanwhile...

I had to hook it up for a first test and was well, disappointed is too weak an expression - this is by far the worst piece of equipment I have listened to in quite a few years...

when i use the aux in, it gets a bit better, but overall not reaching the level of my t-amp...

had to open it , of course:
- Switchmode power supply
- 1 decoder board
- the dvd drive itself
- and: one neatly designed amplifier board with 3 tripath 2020 chips on it

so i am wondering right now:
- is it worth trying to fool around with this one (multichannel digital amplification comes to mind)?
- can i run this on on 12 V SLA-Batteries as well?
anyone ever tried this?

yours qf