Kenwood kr-4600 as a pre-amp to a Kenwood ka-7100 for the main amplifier

[AudiophidliT]

Hi everyone,

EDIT: apologies if "General Audio Discussion" wasn't the best forum for this to be posted in.

I'm currently using a pair of Krix Apex mk3.1 speakers with a Yamaha AS-701, and they're not mingling well enough for my aging ears; the sound is too lacking in musicality and any shread of warmth, which isn't a surprise considering the paring I guess.
It got me thinking; my old man has a Kenwood kr-4600 that apparently would be a nice pairing with my speakers, given the receivers' sound signature and the speakers' detailed presentation. Then I remembered; the amplifier used to start distorting at anything just below 2/3 volume. EDIT: given the speakers' efficiency rating, the receiver might just be enough for my room size, to get away with using just the receiver as the only source of amplification.

Then it occurred to me; Why don't I use the kr-4600 for its sound signature, but the ka-7100 for the power amplifier, therefore at least somewhat keeping some of the kr-4600's sound signature that with these speakers, will hopefully sound quite nice?

The kenwood kr-4600 is all original, but I will be having my father check it over to make sure that it's in full operating health, before auditioning it with my speakers. If it needs any work, he'll do it prior to giving it a whirl. If all goes well but I'd like some more power but without the distortion that they can be known for, at higher levels, then I'll start looking around for a ka-7100. I'm somewhat doing that now, anyway, to get a feel for the price and availability.

I'm limited by budget, but any other ideas to extract the similar sound out of the kr-4600, would be welcomed. I have also considered trying to source a kenwood kr-6600, as the kr-5600 would not be enough of an increase in power, to justify shipping from the USA or Japan, risking damage to it, scarcity of them and therefore overall price etc. I figured that a ka-7100 might be a little easier to find at a fair price even with shipping, if it needs to come from overseas, than if I were to try and secure a kr-6600.

Shoot, it just occurred to me, that if I'm using an American model with a suitable step-down transformer, that wouldn't be compatible as a main amplifier, with a kr-4600 using 240v and no step down transformer, or would it? Just googled it, apparently according to google, it's possible, but I'd be using a decent isolated step-down transformer to hopefully not introduce any noise to the signal chain.

It's probably a long shot, but if anyone's paired a kenwood kr 4600 or a kr 5600 receiver with a ka-7100 as their "power amp", I'd love to know how much of the original receives' soundstage/sound signature came through in the end sound of your speakers.

 

[Dswankey]

...my old man has a Kenwood kr-4600
..Why don't I use the kr-4600 for its sound signature, but the ka-7100 for the power amplifier

I see this is your first post so welcome aboard and here's hoping you enjoy your time on AK

How do you propose connecting the KR-4600 to KA-7100?

 

[AudiophidliT]

I see this is your first post so welcome aboard and here's hoping you enjoy your time on AK

How do you propose connecting the KR-4600 to KA-7100?

Hi Dswankey,

Cheers for the welcome; apparently, according to Google, I could use the kr-pre outs and connect them to the ka-7100.

You'll have to excuse my ignorance, I'm a novice at this stuff. I've since read elsewhere that they're not actually dedicated preouts, but that they can function in this way, if they're connected to a tape monitor input of the intended main amplifier?

 

[Catmanboo]

If you can separate the preamp & power amp sections of the kr4600, (you'll find U-shaped jumpers on the back panel), you're good to patch your preamp of choice into the 4600's power amp section. If this can't be done this way, your workaround may prove unsatisfactory.

 

[painttoad]

do not be fooled by the jumpers on the rear of the kr4600. they are not preamp outputs. they are for an external processor unit(like an eq)

they are before the volume control, meaning that the volume will not affect the output of the connection making it unreasonable to connect an amp there. not that you can't do it but the volume control will not control it and unless the amp had it's own attenuator, it would be full volume all the time.

 

[AudiophidliT]

do not be fooled by the jumpers on the rear of the kr4600. they are not preamp outputs. they are for an external processor unit(like an eq)

they are before the volume control, meaning that the volume will not affect the output of the connection making it unreasonable to connect an amp there. not that you can't do it but the volume control will not control it and unless the amp had it's own attenuator, it would be full volume all the time.

View attachment 3681710

Much appreciated, thank you.

 

[AudiophidliT]

If you can separate the preamp & power amp sections of the kr4600, (you'll find U-shaped jumpers on the back panel), you're good to patch your preamp of choice into the 4600's power amp section. If this can't be done this way, your workaround may prove unsatisfactory.

Thanks for the reply, just been schooled about the kr-4600, it's no go, sadly.

It might actually be enough power to get me by, until I can source a more powerful Kenwood Receiver of the kr model line.

I just really like the colours emitted from the display. It'll always have that nostalgia of when I was young, seeing it at night when listening to music, even if I don't listen to the radio anymore. I remember actually manually seeking radio channels... now, Spotify (and vinyl), suffices.

 

[pauldrewry]

How about adding a tube buffer stage to your current setup?

 

[whoaru99]

Then I remembered; the amplifier used to start distorting at anything just below 2/3 volume.

That isn't inherently an indication of any problem, if that's your implication/concern.

Output is not a direct proportion to volume knob position. In other words 25%, 50%, 75%, 100%, or whatever, volume knob position does not mean the same percentage of output power.

In fact, in a lot of cases particularly with vintage gear, maximum output is achieved well before maximum volume position, and almost certainly that is why you observed what you did. Pretty normal.

 

[whoaru99]

As well, the 60W from the amp might help some but it's not a huge step up in power from the 30(?) watts of the receiver. Might get you a bit more punch but it won't be a big jump in max volume if that is an expectation.

 

[AudiophidliT]

How about adding a tube buffer stage to your current setup?

That sounds like it could be a nice end result, but I know less about tube amplifiers than I know about my pants size, wouldn't know where to start there, unfortunately.

 

[AudiophidliT]

As well, the 60W from the amp might help some but it's not a huge step up in power from the 30(?) watts of the receiver. Might get you a bit more punch but it won't be a big jump in max volume if that is an expectation.

You're right, there... the Krix speakers that I have, and a pair of Pioneer HPM-60's would each, probably need no more than 60watts rms. I'm still considering my options. The post was probably a little premature as I'm still not sure, which way I'm going to go yet, amplification wise or with either of the pairs of speakers. Added to the mix, I'm going to have a look at an Nad 3020B in a couple of days, with the view to it being revamped internally with high quality parts. Hoping for 30watts rms out of each channel, which should be achievable. Worst case scenario, I might just buy an 80's 100watts rms x 2 power amp and put that into either the Kenwood or the Nad.

My father could be getting a little senile in his older age, but give that he's a retired electronic engineer, when he said to me adamantly, that a power amplifier could absolutely be hooked up the the Kenwood kr-4600 (or Nad 3020B), as a power amp, I wasn't going to argue with him (but he could be wrong, it's happened before). Either way, I'm getting closer to getting an amplifier/speaker marriage that will be much more enjoyable for my ears, then what I'm currently listening to. That's the plan, anyway.

(Edit: I forgot to mention it to him, that apparently as Painttoad has said, the pre outs/main ins are before the volume control, he might not be aware of this)

 

[AudiophidliT]

That isn't inherently an indication of any problem, if that's your implication/concern.

Output is not a direct proportion to volume knob position. In other words 25%, 50%, 75%, 100%, or whatever, volume knob position does not mean the same percentage of output power.

In fact, in a lot of cases particularly with vintage gear, maximum output is achieved well before maximum volume position, and almost certainly that is why you observed what you did. Pretty normal.

This might have been common knowledge to my father, but it certainly wasn't to me, thank you for this, I found it to be a fascinating answer.