Amplifier Recommendation

crashb4

Greetings all. Hope you are well. Been a long time, as life has gotten in the way. Some things have changed here at the homestead. I now run SDA SRS V1 (full upgrades), Schiit Freya + pre, Thorens TD-145 MKIII with Ortofon 2M red, a Pi4, Allo Boss2 DAC with Nirvana SMPS power supply for streaming, and a Krell KAV-250a two channel amp. It has come time to replace the amp. Nothing wrong with it, just looking for more umph. Budget is $4,000 to $4500. Looking for suggestions and experiences from you fine folks. I do like the "Krell sound", but I am open to new directions.

TIA for the help.

engie490

I have some questions to help understand the situation:

1. When you say "umph", are you talking strictly about bass?

2. Where are your speakers setup in your room?

3. When you upgraded your speakers, did you change out the SDA inductor?

4. Which mode are you using on the Freya+? Tube? Passive?

crashb4

I am looking for a more authoritative presentation. It is good now, but I don't believe there is enough current with this amp. Bass is not a problem.

Speakers are 6" from the wall. 6' from either side wall, 7' apart. Basement room, concrete walls. Opposing wall is 34'. Overall width 65'.

I changed none of the inductors.

I mostly use the pre in passive mode.

Emlyn

Welcome back.

A Parasound JC5 is a bit above that price point at around $5500 new on sale. A Parasound A21+ is a bit below the price range.

Upgrading the internals on the speakers may help too since they're probably pushing close to 40 years at this point. The Krell amp should be able to push them well as long as everything is working within spec.

crashb4

Emlyn wrote: »

Welcome back.

A Parasound JC5 is a bit above that price point at around $5500 new on sale. A Parasound A21+ is a bit below the price range.

Upgrading the internals on the speakers may help too since they're probably pushing close to 40 years at this point. The Krell amp should be able to push them well as long as everything is working within spec.

The Krell certainly does not fail in any way. For me, it is a bit laid back and is missing some of the energy that live recordings should have. I appreciate that for casual listening, but there are times when raw, in your face power is called for. It just doesn't quite get there. Internals are upgraded except inductors. Also, I am not against second hand equipment. There is good stuff out there.

I truly appreciate the thoughts.

invalid

Does active mode on the preamp make any difference?

crashb4

invalid wrote: »

Does active mode on the preamp make any difference?

Active mode enables the tube section and provides additional gain. There are some really nice sounding tubes out there. I replaced the stock JJ tubes with a set of RCA black base, but that's as far as I have gone. They sound very nice.

jbreezy5

crashb4 wrote: »

I am looking for a more authoritative presentation. It is good now, but I don't believe there is enough current with this amp. Bass is not a problem.

Speakers are 6" from the wall. 6' from either side wall, 7' apart. Basement room, concrete walls. Opposing wall is 34'. Overall width 65'.

I changed none of the inductors.

I mostly use the pre in passive mode.

Is basement room area on sub-flooring? Concrete can affect the sonics big-time.

Krell KAV-250a tended to be a little dry (whole audible frequency range) and very detailed/powerful in the bass in a normal room when I heard it on Dynaudio Audience 82s (my reference floorstanders). Take this with a grain of salt, however, b/c this took place back in 2004 when I bought the Dyn’s.

Dyn’s house sound tends to be a bit dark and polite, but detailed.

Just saying, amp may not be the problem; environment updates may yield better results.

crashb4

jbreezy5 wrote: »

crashb4 wrote: »

I am looking for a more authoritative presentation. It is good now, but I don't believe there is enough current with this amp. Bass is not a problem.

Speakers are 6" from the wall. 6' from either side wall, 7' apart. Basement room, concrete walls. Opposing wall is 34'. Overall width 65'.

I changed none of the inductors.

I mostly use the pre in passive mode.

Is basement room area on sub-flooring? Concrete can affect the sonics big-time.

Krell KAV-250a tended to be a little dry (whole audible frequency range) and very detailed/powerful in the bass in a normal room when I heard it on Dynaudio Audience 82s (my reference floorstanders). Take this with a grain of salt, however, b/c this took place back in 2004 when I bought the Dyn’s.

Dyn’s house sound tends to be a bit dark and polite, but detailed.

Just saying, amp may not be the problem; environment updates may yield better results.

Floor is concrete. I have a bunch of runner rugs starting in front of the speakers and running ten foot out along their axis. Ceiling is eight foot with exposed floor joists. Opposing wall is not treated. I'm considering using layers of blankets to see what some absorption might do. I have no other room treatments. I have looked at acoustic DIY treatments, but time is not plentiful. Guess it's time to make some.

audioluvr

Do you have the dreadnaught? If so I'd recommend Monoblocks.

crashb4

audioluvr wrote: »

Do you have the dreadnaught? If so I'd recommend Monoblocks.

Unfortunately, not for use with V1.0 SRS. I knew that going in. There are 2 channel amps that can still flex a lot of muscle. Krell's Evo 302 and 402 can send 600 and 800 watts respectively to a 4 ohm load. Some have reported luck strapping negative terminals on mono blocks. Don't know that I'm that adventurous. Like to keep the magic smoke in the can.

Emlyn

Compared to other speakers I never really thought my original SDA-SRS speakers were all that authoritative or "punchy" all around. They were really easy and enjoyable to listen to at loud volumes for extended periods once they had the RD0194 tweeters installed. The later SDA models had more punch to them. The SDA-SRS didn't necessarily sound sluggish and there was definitely plenty of smooth bass. It's the smoothness I really liked. Just not a slamming or dynamic type of speaker no matter what I did with them. They did seem to respond to large amounts of power better than smaller amounts.

Have you tried other speakers in that space on the same gear?

crashb4

I haven't even looked at another pair since getting these. I truly enjoy the overall sound of them. I listened to a pair back when they first came out. Saw them in Stereo Review. Went to my local shop in Albany NY to hear them. Said I would own a pair some day. At the time, they were more money than I put as a deposit on my first house. I have addressed the bass punch and that is not the issue. I firmly believe that I don't have near enough current for them. They have all of the detail I could ask for. It's just that final bit of energy that's missing.

jumpindick

May want to consider room treatment as well if budget allows

Emlyn

Current is a good thing with them. I noticed when I ran mine with a Rotel RB-1090 (600+ watts to 4 ohms or something like that) it lifted the soundstage up a couple feet compared to some lower current amps.

crashb4

Funny. I was looking at that exact amp. I had a 1075 multi channel in my previous HT setup. I used it with my SDA-1A and it sounded really nice. My only problem is the age of the amp. They are ready or overdue for re-cap. Not sure if Rotel even does it.

invalid

If you like the krell sound, get a recapped vintage krell with a huge power supply, those are totally different than the one you have now. I'm powering my sda2a's with a ksa 300s and it doesn't lack power for the 2a's which dip down under 4ohm with the new bass inductors.

audioluvr

How about a Belles 350 A Reference? I think someone here has one for sale.

crashb4

invalid wrote: »

If you like the krell sound, get a recapped vintage krell with a huge power supply, those are totally different than the one you have now. I'm powering my sda2a's with a ksa 300s and it doesn't lack power for the 2a's which dip down under 4ohm with the new bass inductors.

That's kinda' the direction I'm leaning. I was looking specifically at the KSA-300s. Trouble is, folks know what it is, and price accordingly. If I can find one in budget, I will go that way.

Emlyn

Rotel makes essentially the same class AB amps once again they were making 20 years ago. Here's a factory refreshed RB-1590 model...

https://www.audioadvisor.com/prodinfo.asp?number=2RORB1590

I had a 1075 model years ago and the RB-1090 was a whole different beast. Although it uses dual transformers it is a common ground design.

crashb4

audioluvr wrote: »

How about a Belles 350 A Reference? I think someone here has one for sale.

Has the 15 amp breaker trip been solved? Or, has it been a problem for that amp. I believe that a large number of the initial offerings had a surge problem on startup that tripped breakers.

audioluvr

Mines the Series 2 which has the soft start.

Edit: series 1 had that issue.

More edit: some issues reported were a background buzz or hum with certain components. (I had this with a tube pre) Rolland at Hi-Tech Audio found the source of the anomaly and corrected it.

crashb4

I had heard that it was addressed. Figured I would ask just in case. There has been a lot of useful information and suggestions. It's just like I never left. You guys are the best. I will be mulling it over for the next week or so, but there will be a change.

Thank you all for taking time to help. Feel free to keep it coming.

audioluvr

With the budget you are setting you could possibly find a good used Pass amp or Rogue Audio.

crashb4

I'm looking for that type of amp. Not necessarily high wattage, but plenty of current. I had an old NAD high current integrated amp, and it was impressive for the 60 watts it was rated at.

jbreezy5

crashb4 wrote: »

jbreezy5 wrote: »

crashb4 wrote: »

I am looking for a more authoritative presentation. It is good now, but I don't believe there is enough current with this amp. Bass is not a problem.

Speakers are 6" from the wall. 6' from either side wall, 7' apart. Basement room, concrete walls. Opposing wall is 34'. Overall width 65'.

I changed none of the inductors.

I mostly use the pre in passive mode.

Is basement room area on sub-flooring? Concrete can affect the sonics big-time.

Krell KAV-250a tended to be a little dry (whole audible frequency range) and very detailed/powerful in the bass in a normal room when I heard it on Dynaudio Audience 82s (my reference floorstanders). Take this with a grain of salt, however, b/c this took place back in 2004 when I bought the Dyn’s.

Dyn’s house sound tends to be a bit dark and polite, but detailed.

Just saying, amp may not be the problem; environment updates may yield better results.

Floor is concrete. I have a bunch of runner rugs starting in front of the speakers and running ten foot out along their axis. Ceiling is eight foot with exposed floor joists. Opposing wall is not treated. I'm considering using layers of blankets to see what some absorption might do. I have no other room treatments. I have looked at acoustic DIY treatments, but time is not plentiful. Guess it's time to make some.

Rugs are good for helping with reflection challenges, however, concrete doesn't vibrate/resonate like a sub-floor. Think of it like if you compare the sonics of an upstairs system to your basement; the tonality is completely different in a concrete basement setting.

Emlyn wrote: »

... Have you tried other speakers in that space on the same gear?...

Exactly.

Additionally, a little bit of audiophile heresy here... Have you tried EQ of any kind to hear what frequency ranges most improve the sense of authority you are seeking in the basement environment? This could be a low-cost way to find out what it is you're really after (even if you fully intend to remove the EQ).

You can even use an app, such as SonicTools (no affiliation), to get a visual analysis of your frequency response in the basement. It ain't exact, but can give you some perspective regarding what you're hearing.

crashb4

I stream with Volumio. It has an EQ plugin. I have run it and fiddled around with it. Truth is, it sounds best flat. I do have a pool table between the speakers and opposing wall. The high end is a bit calmer since putting it in. I am going to layer blankets on the opposing wall to see what some absorbing material does. I am more than capable of building some rock wool panels to hang on the walls and on stands along the sides. I can also pile more rugs on the floor, But there is no softening the floor or walls.

crashb4

jbreezy5 wrote: »

crashb4 wrote: »

jbreezy5 wrote: »

crashb4 wrote: »

I am looking for a more authoritative presentation. It is good now, but I don't believe there is enough current with this amp. Bass is not a problem.

Speakers are 6" from the wall. 6' from either side wall, 7' apart. Basement room, concrete walls. Opposing wall is 34'. Overall width 65'.

I changed none of the inductors.

I mostly use the pre in passive mode.

Is basement room area on sub-flooring? Concrete can affect the sonics big-time.

Krell KAV-250a tended to be a little dry (whole audible frequency range) and very detailed/powerful in the bass in a normal room when I heard it on Dynaudio Audience 82s (my reference floorstanders). Take this with a grain of salt, however, b/c this took place back in 2004 when I bought the Dyn’s.

Dyn’s house sound tends to be a bit dark and polite, but detailed.

Just saying, amp may not be the problem; environment updates may yield better results.

Floor is concrete. I have a bunch of runner rugs starting in front of the speakers and running ten foot out along their axis. Ceiling is eight foot with exposed floor joists. Opposing wall is not treated. I'm considering using layers of blankets to see what some absorption might do. I have no other room treatments. I have looked at acoustic DIY treatments, but time is not plentiful. Guess it's time to make some.

Rugs are good for helping with reflection challenges, however, concrete doesn't vibrate/resonate like a sub-floor. Think of it like if you compare the sonics of an upstairs system to your basement; the tonality is completely different in a concrete basement setting.

Emlyn wrote: »

... Have you tried other speakers in that space on the same gear?...

Exactly.

Additionally, a little bit of audiophile heresy here... Have you tried EQ of any kind to hear what frequency ranges most improve the sense of authority you are seeking in the basement environment? This could be a low-cost way to find out what it is you're really after (even if you fully intend to remove the EQ).

You can even use an app, such as SonicTools (no affiliation), to get a visual analysis of your frequency response in the basement. It ain't exact, but can give you some perspective regarding what you're hearing.

What a fantastic idea. Didn't even think to try an analyzer. I may have gone overboard with the rugs. There is a sharp drop-off at 10Khz. Didn't expect that. Otherwise, it looks pretty good. It's not the most accurate, but does show something.

engie490

Krell KSA-300 is fully balanced, so that would be a no-no with early SRS.

Belles is powerful, but laid back…which is what the OP is doesn’t want.

I have the Belles 350A (1st gen) and it has never tripped a breaker on me. YMMV.

One question I have for the OP is if you’ve used an active solid state preamp with the KAV250?

Btw, I grew up in the Albany area.

invalid

The krell ksa 300s is not differential balanced it has balanced inputs and single ended inputs.

crashb4

The FPB series is differential balanced, and a big no no. I have used an Adcom SS preamp with the Krell. Was not impressed. I can tell you that the tube stage on the Freya+ is sweet sounding with the RCA 6SN7 tube. I would love to find a set of red base that didn't cost my first born.
I came across a Rotel RB-1090 at an attractive price. I am going to pick it up today. At the price I got the two amps at, I will easily recoup my money. I had a Rotel 1075 in a HT setup a while back, and it sounded great with the SRS-1A. I'll give it a try. Nothing to loose.