[Wayne1]

I finally got a chance to take a look inside this receiver.

It is pretty cool

It uses a straight linear power supply with a HUGE transformer. Standard full wave bridge diodes and power supply caps. It has separate, regulated power suppies for low voltage.

There are quite a few electrolytic coupling caps in the analog signal path. In fact all of the preamp signal path is analog.

The amp section is divided into 5 separate modules. These modules can be unplugged from the main board, after unsoldering the grounding case.

The amp modules look very similar to the Tripath module, but I do not see any marking from Tripath.

There are LOTs of things that can be changed in this little receiver. Most of the capacitors, the bridge rectifiers, pulling some of the modules to just use the amp in stereo, etc.

I am getting some plates made to install two pair of binding posts in place of the spring clips. There is not room for 5 pair, however.

I will be checking out pricing on the upgraded parts and will update everyone about mod options.

[TheChairGuy]

Now we're talking Wayne!  

[mcgsxr]

Cool to read that the older model may have a lot of potential - glad I just sold it to my best friend - dough!

Ah well, I look forward to playing with the toys that I have coming, so I am really glad that he might be able to benefit from some of this!

[Jay S]

Hi Wayne,

A JVC receiver may be right up my alley -- do keep us in the loop on these mods.  I am interested in the ES1 (I understand it is more musical and is better at driving difficult loads than the FS10), but have you seen the latest models which have the USB digital input?  I hope that JVC has improved the D/A section as it would be great to feed a digital signal direct from a PC.  

Cheers,

- Jay

[tubeytubeamp]

Wayne,

Do you recall if the heaphone output is an Op-amp design or is it feed directly off the amp of the JVC receivers.

All things considered, the headphone output doesn't sound too bad. What upgrades if any can be made to the output?

Thanks
Dennis

[ooheadsoo]

tubeytube, what have your compared the headphone out to?  IMO, it's the worst headphone out I have ever heard.

[TheChairGuy]

Not to swipe Wayne's Bolder forum, but I gotta' agree with ooheadsoo on this one...absolutely terrible headphone output.  I've never heard a portable walkman of any $$ that was worse.

And Jay, I think you mixed things up a bit...the F10 drives difficult loads, but I found the older ES1sl to be more musically pleasing.  Oddly, it sounds to me like the best piece of tube gear I've ever heard on good power conditioning.  As JVC seems to be committed to use of analog and digital feedback in their designs,  their digital input is likely to stay inferior to the analog inputs on future models...if sound quality is your only goal.  We'll hear soon, tho.

[Jay S]

TCG,

Thanks for the clarification!  I am planning on an ES1 unless the new line of receivers approaches them in sound quality.  My speakers are 2-ways so they aren't a difficult load.  I'm really glad to hear that the ES1 sounds like good tube gear when plugged into a good power conditioner -- I enjoy the sound of tubes + power (a challenging combination but I think approached by my current tube pre + digital amp setup) and my future JVC will be plugged into a Bolder balanced power supply.  

I am not clear on the technical aspect of why JVC would keep the digital input inferior unless you are referring to the fact that the signal would have to go through an additional D-A conversion stage.  This is the opposite I guess of why the Panny receivers sound better with digital inputs (i.e. they are all digital and convert A-D before feeding into the amp section).  

Regards,

- Jay

[TheChairGuy]

Yep Jay, as I understand it, a digital signal does not stay in digital domain with the current crop of JVC's...but it does some real nice things amplifying the analog signals.  Yes, indeedy.

fyi, I'm not in any way a tube lover...I yawn repeatedly when I hear the bottled stuff.  But, the ES1sl has a sound that is broadly reminiscent of tubes, but does everything (an opinion) that I think is lacking in tube amplification.

Sorry for the heist, Wayne  

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